Dipolar interaction-mediated molecular anchoring electrolyte enables wide-temperature sodium-ion batteries with enhanced safety and durability

Dipolar interaction-mediated molecular anchoring electrolyte enables wide-temperature sodium-ion batteries with enhanced safety and durability | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Dipolar interaction-mediated molecular anchoring electrolyte enables wide-temperature sodium-ion batteries with enhanced safety and durability Xing-Long Wu, Yong-Li Heng, Zhen-Yi Gu, Han-Hao Liu, Xiao-Tong Wang, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6768086/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Given intractable challenges faced by practical sodium-ion batteries (SIBs) in safety, ultralong lifespan and broad temperature adaptability with synergistic interfacial compatibility, persistent efforts in electrolyte engineering are imperative to expedite their commercialization. Here we design a molecular anchoring electrolyte with remarkable flame retardancy, oxidative/reductive reliability and electrochemical durability against both electrodes. Through multiple dipolar interactions (δ + H-δ - F, δ + H-δ - O and δ + H-δ - N), a dynamic hierarchical solvation network is constructed and its unique interface stabilization mechanism is revealed by multiscale characterizations and theoretical insights. The electrolyte endows high-voltage phosphate cathode with extraordinary electrochemical durability (87.6% of capacity retention after 5000 cycles) through constructing robust interphases enriched with F and N. Great compatibility with commercial layered oxide further indicates its versatility. Strikingly, the electrolyte also sustains stable operation under extreme temperatures (-60 ~ 70 °C). Our proposed dipolar interaction regulation mechanism provides a new paradigm for designing safe and durable electrolytes, stimulating practical application of wide-temperature SIBs in extreme environment energy storage. Physical sciences/Chemistry/Energy Physical sciences/Energy science and technology/Energy storage/Batteries sodium-ion battery molecular anchoring electrolyte dipolar interaction interfacial modulation non-flammability Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Introduction SIBs are emerging as ideal candidates for next-generation large-scale energy storage technologies due to their significant resource advantages, environmental friendliness and potential economic benefits 1 , 2 . Unfortunately, despite tremendous breakthroughs in electrode materials like layered oxides and polyanionic compounds 3 , 4 , 5 , 6 , the commercialization of SIBs remains constrained by two critical technical bottlenecks: (i) under high-voltage conditions (> 4.2 V), electrochemical durability and interfacial compatibility with highly reactive electrodes is insufficient for conventional electrolyte systems, causing limited lifespan 7 , 8 ; (ii) in extreme temperature environments ( 60°C), sharp decline in ionic conductivity of electrolytes and exacerbation of interfacial parasitic reactions accelerate battery failure 9 , 10 , severely restricting their application in special scenarios (e.g., polar exploration, aerospace). Particularly, safety concerns should not be underestimated for battery sustainability 11 . The essence of these problems lies in multiscale failure mechanisms of conventional electrolytes: at the molecular level, thermodynamic instability of solvation structures causes uncontrolled oxidation decomposition kinetics at high voltages; from an interfacial perspective, insufficient mechanical strength and chemical inertness of electrode-electrolyte interphases (EEIs) fail to suppress mechanical fracture and parasitic reaction penetration during cycling 12 , 13 . Existing research faces trade-off dilemmas, including energy density reduction (e.g., capacity loss in cathodes caused by high-salt systems) or process economic efficiency deterioration (e.g., skyrocketing costs of fluorinated solvents) 14 , 15 . How to achieve multiscale synergistic optimization in electrolyte solvation, interfacial mechanics and electrochemical stability remains a key scientific challenge for practical application of SIBs. Electrolytes, serving as the “ion transport hub” of batteries, profoundly affect electrochemical properties and interfacial chemistry through their solvation structures 16 , modulated by intermolecular interactions (ion-ion, ion-dipole and dipole-dipole). In conventional carbonate (e.g., EC, PC) and ether-based (e.g., DME, G2) electrolytes, strong cation-dipole interactions predominantly promote the formation of solvent-separated ion pairs (SSIPs), facilitating salt dissociation and high ionic conductivity 17 , 18 . Unfavorably, they bring about vulnerable EEIs rich in organic components, which tend to rupture and fail under cyclic stress. Additionally, excessive free solvents undergo persistent parasitic reactions at the interfaces during the cycle, thus drastic electrochemical deterioration occurs. To address this dilemma, solvation engineering has made critical breakthroughs: except for prevalent (localized) high-concentration electrolytes with enhanced anion coordination to form inorganic-rich EEIs 19 , 20 , 21 , emerging weakly solvating electrolytes with reduced cation-dipole interactions enable contact ion pairs (CIPs) and aggregates (AGGs) to accumulate and dominate 22 , 23 , 24 , 25 , constructing high-modulus EEIs. Nevertheless, these approaches are plagued by low salt solubility, high viscosity and excessive fluoride dependence 26 . Lately, hybrid strongly and weakly solvating electrolytes (e.g., THF/DMTMSA 27 ) allow for synchronous optimization in both cathodes and Na metal anode by regulating ion-dipole interactions and solvation configurations. Furthermore, entropy regulation effects have been introduced into electrolyte design, leveraging configurational entropy to inhibit solvent crystallization, demonstrating great promise for applications under extreme conditions 28 , 29 , 30 . Nonetheless, relevant research remains in its infancy, extensive exploration is required. Additionally, considering persistent safety concerns, abundant flame-retardant systems including phosphates 31 , 32 , fluorinated phosphazenes 33 , 34 , and ionic liquids are discovered to reduce self-extinguishing times but bring about new issues like high viscosity, poor wettability and incompatibility with anodes 35 , 36 . The current core challenge lies in balancing conflicting parameters such as ionic conductivity, interfacial stability, cost and environmental friendliness, which necessitates persistent rational design and exploration. Herein, we conducted a comprehensive analysis of prevalent carbonate and ether-based solvents to further elucidate their intrinsically complementary characteristics. On this basis, a dipolar interaction-mediated molecular anchoring electrolyte engineering was conceived to integrate strongly solvating ester (PC), weakly solvating ether (DEE) and anti-solvent (PFPN) for safe and durable SIBs under extreme conditions. Particularly, not only anion-dipole interactions via δ + H-δ − F between PF 6 − and PC or PFPN but also dipole-dipole interactions via δ + H-δ − O and δ + H-δ − N between PC and PFPN have been deciphered through spectroscopic and theoretical investigations, effectively activating PFPN anti-solvent and restricting free PC/DEE molecules by anchoring effect from PFPN. Through modulating dipolar interactions, the electrolyte enables great compatibility with both anodes and high-voltage cathodes, accompanied by construction of robust EEIs rich in F/N. Consequently, representative high-voltage phosphates, layered oxide cathodes and hard carbon (HC) anode demonstrate extraordinary cycling stability, e.g., 87.6% of reversible capacity after 5000 cycles for Na 3 V 2 (PO 4 ) 2 O 2 F (NVPOF) model cathode. Conspicuously, the electrolyte also sustains successful operation under wide temperatures (-60 ~ 70 ℃) with admirable capacity retention of 95.2% over 900 cycles at 70 ℃ and 51.2 mAh g − 1 of reversible capacity at -60 ℃ for Na 3 V 2 (PO 4 ) 3 (NVP). This work reveals a dipolar interaction-mediated solvation-interface synergistic stabilization mechanism and establishes a “molecular anchoring-solvation configuration-interfacial dynamics” structure-property relationship, providing new insights into the advancement of safe and durable electrochemical systems under extreme conditions like polar exploration and deep space missions. Results Comparative analysis of prevalent carbonates and ethers There is a trade-off between conventional carbonate and ether-based solvents from the perspective of electrolyte design. Integrated electrolyte engineering has attracted great attention due to their promise of comprehensive electrochemical properties, especially the following critical aspects: battery lifespan, energy efficiency, cost effectiveness and safety concerns ( Fig. 1a ). Careful selection of sodium salts, solvents and additives is essential to electrochemical properties. Generally, NaPF 6 is deemed as an ideal sodium salt when taking solubility, conductivity, chemical/thermal stability, toxicity and corrosive nature into account together, compared to other sodium salts like NaBF 4 , NaClO 4 , NaOTf and NaFSI 37 . Furthermore, it is recognized that carbonates and ethers constitute two primary solvent systems in SIBs that have been extensively investigated. Basic physicochemical properties of representative carbonate and ether solvent molecules have been summarized in Fig. 1b and Supplementary Table s 1 , 2 . Cyclic carbonates like EC and PC exhibit the dielectric constants far greater than those of other solvents, indicating high solvation ability and ionic conductivity. Among them, PC possesses the widest liquid range with low melting point (-48.8 ℃) and high boiling point (242 ℃), conducive to sustaining a wide service temperature range of batteries 38, 39 . EC is solid with 36.3 ℃ of melting point and difficult to use alone 40 . Generally, ethers exhibit low melting and boiling points, especially THF and MeTHF, which are volatile and prone to oxidation 41, 42 . DEE demonstrates a moderate melting and boiling point (-74 and 121 ℃, respectively). In addition, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of these solvents are calculated based on density functional theory (DFT) to determine their oxidation and reduction properties ( Supplementary Fig. 1 ). Generally, carbonates have significantly lower HOMO levels, indicating higher oxidation stability and thus excellent compatibility with high-voltage cathodes. Meanwhile, their lower LUMO levels imply inferior reduction stability and thus poor compatibility with anode. In contrast to carbonates, ethers demonstrate higher HOMO and LUMO energy levels, manifesting worse oxidation stability while better reduction stability. Binding energy calculations with optimized structures for various Na + -solvent complexes are conducted, as depicted in Supplementary Fig. 2 , where EC, PC and DME possess significantly lower binding energy with Na + while G2 and DEE exhibit the higher values. Furthermore, for rational electrolyte design, electrostatic potential (ESP) analysis of these solvent molecules is demonstrated in Fig. 1c , which is a crucial descriptor to further elucidate interactions between Na + and solvents 43, 44 . Their negative charges are mainly localized at oxygen atoms, which are prone to coordinate with Na + . Among them, strong polar PC exhibits a minimum ESP min with |ESP min | > ESP max , implying strong coordination ability. While DEE molecule shows less negative ESP min and significantly decreased ESP max , accompanied by more uniformly distributed electron density, indicating decreased Na + solvation power. Based on above considerations, PC and DEE with significantly complementary characteristics are selected to function synergistically as solvents in pursuit of integrated electrolyte design ( Fig. 1d ). Design logic of integrated solvating electrolyte Note that simple blending of PC and DEE is difficult to achieve desired properties and cannot make full use of their advantages ( Supplementary Fig. 3 ). More importantly, conventional carbonate and ether solvents are volatile and combustible, posing a serious threat to battery safety. Consequently, PFPN is introduced into the integrated electrolyte system to leverage its prominent advantages as follows. Primarily, based on synergistic effect of the condensed phase flame retardant mechanism and free radical trapping mechanism 45 , PFPN is deemed as an excellent flame retardant on account of abundance of F, N and P elements, as detailed in Fig. 2b . On the one hand, PFPN can form a dense and sturdy carbon layer when subjected to high temperatures, effectively isolating oxygen. On the other hand, fluorine, nitrogen and phosphorus free radicals ([F]∙, [N]∙ and [P]∙) produced by PFPN can trap active free radicals (such as H∙ and HO∙) in the combustion chain reaction, thereby interrupting the combustion process. Additionally, PFPN decomposition can produce non-flammable gases like N 2 and NH 3 , which dilutes the concentration of combustible gas and reduces the combustion intensity. Besides, PFPN exhibits reduced HOMO and LUMO energy levels compared to those of conventional carbonates and ethers, demonstrating its outstanding antioxidant capacity and preferentially involved in SEI formation. Furthermore, ESP analysis of PFPN is performed to elucidate the charge distribution. It can be found that PFPN exhibits a significantly higher ESP min and the |ESP min | is much lower than ESP max , indicating its non-solvation property. Nevertheless, it can regulate solvation structure through intermolecular dipolar interactions and a unique anchoring effect has been proposed, which will be elaborated in the following sections. In view of above factors, an integrated solvating electrolyte was formulated with 0.8 M NaPF 6 dissolved in weakly solvated DEE, strongly solvated PC and non-solvated PFPN, denoted as NDPP ( Supplementary Table 3 ). Additionally, two control electrolytes have also been proposed, namely ND (0.8 M NaPF 6 in DEE) and NP (0.8 M NaPF 6 in PC). As illustrated in Fig. 2a , it is anticipated that the developed NDPP electrolyte has several remarkable characteristics with nonflammability, intricate intermolecular interactions and good compatibility with cathode and anode, in sharp contrast to ND and NP electrolytes. Furthermore, ionic conductivity of ND, NP and NDPP electrolytes is 1.31, 5.73 and 5.81 mS cm -1 , respectively, as displayed in Fig. 2c . The ND electrolyte displays an extremely low ionic conductivity due to weak solvation of DEE. Additionally, oxidation/reduction stability of different electrolytes have also been evaluated via linear sweep voltammetry (LSV) measurements ( Fig. 2d, e ). As expected, NDPP electrolyte exhibits not only enhanced anti-oxidative capacity (up to 4.85 V) but also prominent reduction stability due to the synergy effect involved in PFPN, verifying the effectiveness of PFPN in enhancing redox stability and thus compatibility with both high-voltage cathodes and anodes. Remarkably, NDP electrolyte obtained by simply blending PC and DEE still shows unsatisfactory redox stability, which substantiates the indispensable role of PFPN. This result can also be further confirmed by the following electrochemical investigations. Moreover, flammability tests of electrolytes are displayed in Fig. 2f and Supplementary Videos 1-3 . Predictably, NDPP electrolyte demonstrates inherently non-flammable properties, attributed to the introduction of flame-retardant PFPN. Whereas ND and NP electrolytes are obviously flammable, leading to serious security concerns. Decipherment of dipole interactions Generally, intricate intermolecular interplay involving ion-ion, ion-dipole and dipole-dipole interactions are present in the electrolytes, demonstrating a crucial role in manipulating solvation and interfacial chemistry 46, 47 . To comprehensively understand these interactions, extensive spectral and theoretical investigations were conducted. Raman analysis of salt, solvents and electrolytes were executed to identify intermolecular interactions among various electrolyte components ( Fig. 3a ). Notably, there is a strong peak at 728.1 cm -1 in NDPP, assigned to PFPN. Meanwhile, this peak exhibits a red shift compared to pure PFPN solvent, indicating the presence of interactions between PFPN and other electrolyte components (e. g., PF 6 - , PC and DEE). Furthermore, for ND, NP and NDPP electrolytes, the peak appears at 729~744 cm -1 can be attributed to coordinated PF 6 - . Additionally, the coordinated DEE and PC can be observed in ND, NP and NDPP electrolytes. More evidence for the changes in interactions can be elucidated by nuclear magnetic resonance (NMR) investigations. Fig. 3b presents 19 F NMR spectra of different electrolytes. From ND, NDPP to NP, P-F peaks in PF 6 - shift upfield, which stems from an increase in electron cloud density around F, manifesting the reduced interaction between Na + and PF 6 - in NP electrolyte. To gain deep insights into intricate interactions in NDPP electrolyte, we employed a 2 D 1 H- 19 F heteronuclear overhauser effect spectroscopy (HOESY) study 48, 49 . As delineated in Fig. 3c , several distinct cross signals indicate the interactions between PF 6 - anions and PC or PFPN solvents through δ + H-δ - F. Note that existence of the interactions between PFPN molecules can also be observed. Furthermore, interactions among various electrolyte components can be in-depth investigated through theoretical calculations. Fig. 3d and e demonstrate their binding energy calculations with the corresponding optimized structures. Among them, there are relatively strong interactions between PC and PF 6 - through δ + H-δ - F, moderate interactions between PFPN and other electrolyte components (DEE, PC and PF 6 - ) through δ + H-δ - F, δ + H-δ - O and δ + H-δ - N. Consequently, non-coordinated PFPN in NDPP can be activated via dipolar interactions with vulnerable PC and DEE can be anchored, which ameliorates the solvation environment and interfacial chemistry, conductive to electrochemical improvements. Note that the interactions between Na + cation and other compositions, especially PF 6 - anion are significantly stronger through the coordination between Na + and O/N/F atoms ( Supplementary Fig. 4 ). Identification of electrolyte solvation structures To shed light on the evolution of Na + solvation structure, classic molecular dynamics (MD) simulations of different electrolyte systems were implemented and snapshots are illustrated in Fig. 4a-c . Particularly, their representative solvation configurations with electron distribution through ESP analysis are presented to further elucidate the fundamental ion-solvent chemistry. In these Na + -anion-solvent complexes, negative charges are mainly contributed on the surface of PF 6 - anions. Additionally, for NP and NDPP electrolytes, stronger affinity between PF 6 - and PC engenders electron delocalization in the complexes, leading to more scattered charge distribution compared to that in ND electrolyte. More detailed information about Na + solvation structures can be obtained by further analysis of radial distribution functions (RDFs) and the corresponding coordination numbers (CNs) from MD simulations, as displayed in Fig. 4d-g . In ND electrolyte, an initial peak corresponding to Na + -O(DEE) species appears at approximately 2.27 Å while that of Na + -F(PF 6 - ) is located at 2.23 Å. Also, their CN values are calculated as 3.61 and 2.43, respectively. This result may be attributed to weak solvation capability of DEE and thus lead to the formation of anion-derived EEIs, consistent with previous literature. While in NP electrolyte, initial peaks of Na + -O(PC) and Na + -F(PF 6 - ) are observed at 2.28 and 2.18 Å, respectively, and the corresponding CN of PC is up to 4.48 but that of F in PF 6 - is only 1.77. Consequently, such a significant difference in CN drives the generation of PC derived organic-dominated EEIs. This phenomenon is in agreement with strong coordination capability of PC with Na + . Furthermore, for the integrated NDPP electrolyte, initial peaks of Na + -O(PC), Na + -O(DEE) and Na + -F(PF 6 - ) are identified at 2.23, 2.32 and 2.18 Å with CN values of 2.98, 1.61 and 1.68, respectively, indicating competitive coordination of these solvents/anions, which facilitates the formation of hybrid inorganic/organic coupling EEIs. Notably, more Na + -solvent complexes are conducive to enhancing antioxidant capacity of solvent molecules particularly PC and DEE. Meanwhile, there is a negligible initial peak of Na + -N(PFPN), implying that PFPN essentially does not coordinate with Na + . Nevertheless, as aforementioned, the existence of dipolar interactions between PFPN and other solvents/anions can activate the anti-solvent, undoubtedly having a certain impact on the holistic solvation environment. As illustrated in Fig. 4h , intricate interaction relationship among Na + , solvents and anion in NDPP electrolyte is distinctly demonstrated. Particularly, the coordinate bond generally exists between Na + cation and PF 6 - anion. In addition, electrostatic interactions including ion-dipole and dipole-dipole are present between electrolyte components (e. g., δ - F in PF 6 - and δ + H in PC or PFPN), as mentioned earlier in Fig. 3 . These findings confirm the variations in interactions and solvation configurations from weakly solvated ND and strongly solvated NP to integrated solvating NDPP electrolytes. Evaluation of electrochemical properties We proceeded to evaluate the developed electrolytes for long-term electrochemical durability of representative cathodes (e. g., NVPOF, NVP and NT0102) and HC anodes. Initially, Fig. 5a demonstrates the first galvanostatic charge-discharge (GCD) profiles of NVPOF//Na half cells with different electrolytes at 0.1 C and room temperature (RT). Compared with ND and NP, the integrated NDPP electrolyte allows for the optimal electrochemical behavior in terms of discharge specific capacity (from 118.07, 118.58 to 123.80 mAh g -1 ), initial CE (from 80.56%, 77.27% to 92.39%) and EE (from 79.78%, 75.41% to 90.32%). Furthermore, their cycling stability was investigated at 2 C and RT ( Fig. 5b ). Remarkably, the NVPOF cathode in NDPP sustains 87.6% of capacity retention even after 5000 cycles, along with persistently stable CEs. In sharp contrast, there are significant capacity attenuation for NVPOF//Na half cells with ND and NP electrolytes, accompanied by 75.6% and 81.6% of capacity only after 450 cycles, respectively. Meanwhile, GCD curves after different cycles are disclosed in Fig. 5c and Supplementary Fig. 5 , indicating a more stable voltage polarization phenomenon in NDPP electrolyte. Additionally, evolution of EE during the cycle can be discovered, which further highlights the reliability of NDPP electrolyte. Overall, the integrated electrolyte has demonstrated significant advantages from the following perspectives: ionic conductivity, oxidation stability, reduction stability, electrochemical durability and safety, compared with ND and NP electrolytes ( Fig. 5d ). Moreover, cycling stability was also tested when commercial sodium nickel iron manganese oxide (NT0102) was applied as the cathode in SIBs. NT0102//Na half cells coupled with NDPP electrolyte are capable of maintaining steady operation for 350 cycles at 1 C with 80.5% of capacity retention, as shown in Fig. 5e . Additionally, NVP is also employed as a model cathode, aiming to further determine the universality of NDPP electrolyte ( Supplementary Fig. 6 ). Remarkably, there is no capacity decline for NVP//Na half cells during 2500 cycles at 10 C and RT, delivering ~93 mAh g -1 of reversible capacity. More importantly, practical feasibility of the integrated NDPP electrolyte under extreme conditions (particularly wide temperatures) was further demonstrated. Initially, the formulated NDPP electrolyte not only remains liquid without salt precipitation after storage at -60 ℃, but also still demonstrates good chemical stability at 60 ℃, as shown in Supplementary Fig. 7 . As expected, NVPOF//Na half cells with NDPP electrolyte display excellent cycling stability at 5 C and high temperatures, with 92.4% of capacity retention after 1500 cycles at 50 ℃ and 90.8% after 500 cycles at 60 ℃ ( Supplementary Fig. 8 ). Their GCD curves at different cycles are demonstrated in Supplementary Fig. 9a and b , indicating stable and reversible electrochemical behaviors at high temperatures. When the temperature rises further to 70 ℃, the NVPOF cathode exhibits a significantly irreversible process when charging and thus low CE ( Supplementary Fig. 9c ), triggered by severe oxidative decomposition of the electrolyte and side reactions between cathode and electrolyte. Nevertheless, inferior low-temperature performance can be observed for NVPOF//Na half cells with NDPP electrolyte at -25 and -40 ℃ ( Supplementary Fig. 10 ), which may be attributed to restricted electronic and ionic conductivities from NVPOF material. Additionally, electrochemical investigations of NVP cathode at different temperatures were also carried out to further evaluate the wide-temperature adaptability of NDPP electrolyte. Supplementary Fig. 11 and Fig. 5f demonstrate its typical GCD curves and remarkable cycling stability at high temperatures, specifically, NVP//Na half cells exhibit 95.2% and 94.2% of capacity retentions after 1000 cycles at 50 and 60 ℃, respectively. Even at 70 ℃, 95.2% of capacity can be maintained after 900 cycles. For low-temperature research, unlike NVPOF, NVP cathode is employed due to its relatively higher electronic conductivity. As expected, NVP//Na half cells with NDPP electrolyte deliver superior electrochemical properties at -40 and -60 ℃ ( Fig. 5g ), with 70.2 and 51.2 mAh g -1 of reversible capacity at 0.1 C, respectively. Furthermore, remarkable cycling stability can also be identified, as shown in Supplementary Fig. 12 . These investigations have forcefully proved the feasibility of stable operation of NDPP electrolyte for different cathodes even under wide temperatures. In addition to being compatible with various cathodes in SIBs, electrolyte must also cater to the anodes to achieve practical application of full cells. Supplementary Fig. 1 3 is typical GCD profiles of HC anodes in different electrolytes. As expected, HC//Na half cell with NDPP demonstrates a moderate reversible capacity close to 320 mAh g -1 at 25 mA g -1 compared to those of ND and NP electrolytes. Furthermore, their electrochemical stability tests were also conducted ( Supplementary Fig. 14 ). The integrated NDPP electrolyte is conducive to excellent cycling stability. Based on above findings, a representative NVPOF//HC full cell was assembled and its electrochemical properties were investigated, as demonstrated in Supplementary Fig. 15 . It delivers a high initial specific capacity of 119.7 mAh g -1 accompanied by a CE of 90.33% at 0.1 C and cycling stability with 79.1% of capacity retention after 1000 cycles at 2 C. Multiscale analysis of interfacial chemistry Interfacial stability plays a crucial role in electrochemical improvement. To evaluate interfacial effects on cathode and anode after cycling in different electrolyte systems, surface morphology of the cycled NVPOF and HC in various electrolytes were characterized by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) techniques, as displayed in Fig. 6a and Supplementary Figs. 16-18 . Remarkably, the NVPOF cathode cycled in NDPP electrolyte appears intact without visible fissures. Simultaneously, a thin, compact and smooth CEI layer can be observed with a thickness of only 3.3 nm. These manifest harmful side reactions between cathode and electrolyte are effectively suppressed. Contrastingly, there are disrupted morphologies and significant microcracks, with thick and nonuniform CEI layers on NVPOF cathodes cycled in ND and NP, which are responsible for their poor CE and electrochemical stability. For HC anode, when cycling in ND electrolyte, it exhibits better surface morphology with a thinner SEI layer (15.5 nm), verifying better compatibility of weakly solvating electrolyte with anode. Whereas, NP electrolyte demonstrates inferior compatibility with HC anode, accompanied by distinct microcracks, a thick and nonuniform SEI layer on the electrode surface, which stems from continuous decomposition and accumulation of carbonate solvents. For NDPP electrolyte, moderate compatibility with HC anode can be obtained with a well-maintained surface morphology through constructing an even and dense SEI layer. These investigations substantiate effectiveness and feasibility of the integrated electrolyte engineering in collaborative interface regulation and admirable compatibility with anodes and high-voltage cathodes for durable SIBs. To further identify specific chemical compositions of EEIs, we conducted X-ray photoelectron spectroscopy (XPS) analysis of cycled NVPOF cathodes and HC anodes with different electrolytes, as revealed in Fig. 6b and Supplementary Fig. 19 . C 1s spectra reveal organic species (e. g., C-C, C-O and C=O), derived from the decomposition of free solvent molecules (PC, DEE). Additionally, F 1s spectra display two distinct peaks, corresponding to PO x F y and NaF, primarily derived from NaPF 6 salt. Comparative analysis manifests hybrid organic-inorganic coupling interfaces through the integrated solvating electrolyte design. Besides, the presence of N-containing species in the CEI and SEI layers with NDPP electrolyte is detected from N 1s spectral analysis, demonstrating PFPN involves in interface modulation ( Supplementary Fig. 20 ). Additionally, surface roughness and 3 D topography analysis of cycled electrodes with different electrolytes were characterized by atomic force microscopy (AFM), as shown in Fig. 6c and Supplementary Fig. 2 1 . Specifically, the cycled NVPOF cathode in NDPP electrolyte exhibits a notably smoother morphology with a surface roughness of 57.4 nm, compared to those in ND and NP electrolytes (66.6 and 91.4 nm, respectively), consistent with above findings. Furthermore, time-of-flight secondary ion mass spectrometry (TOF-SIMS) was employed to explore component distribution in the CEI 50, 51 . Fig. 6d and Fig. 6e demonstrate 2 D and 3 D reconstruction images of CHO 2 - , NaF 2 - and PO 2 F - fragments on the cycled NVPOF cathode in NDPP, indicating the establishment of a thin, uniform and robust organic-inorganic coupling interface, in align with XPS results. Among them, organic components can promote mechanical strength and flexibility of the interface to effectively alleviate electrode deformation, while inorganic species exhibit high ionic conductivity and electronic insulation, conducive to enhancing interfacial stability 52, 53 . Additionally, oxidation and reduction properties of electrolytes were calculated to further deduce the interfacial compatibility ( Fig. 6f ). According to the corresponding HOMO/LUMO energy levels, anti-oxidation stability of solvents is found to follow the sequence of PFPN > PC > DEE, while their anti-reduction stability is PFPN < PC < DEE. The integrated electrolyte demonstrates superior oxidative stability for high-voltage cathodes and compatibility with anodes due to introduction of PFPN. For Na + -solvent complexes, they exhibit declined HOMO/LUMO energy levels, revealing enhanced anti-oxidation stability and weakened anti-reduction stability. Nevertheless, Na + -solvent-PF 6 - complexes have moderate redox stability with intermediate HOMO/LUMO energy levels. Overall, hybrid organic-inorganic coupling EEIs rich in F/N can be constructed on electrodes, leading to prominent interfacial and electrochemical stability. Fig. 7 schematically illustrates comprehensive assessments of conventional ND, NP and our designed NDPP electrolytes. Through multiscale experimental and theoretical investigations, NDPP has demonstrated remarkable merits in the following aspects: enhanced ionic conductivity, great compatibility with both electrodes due to synergistic oxidation and reduction stability, prominent electrochemical durability, and mitigated safety threat from non-flammability. Particularly, solvation and interfacial chemistry play a crucial role in electrochemical properties. For ND electrolyte with weakly solvated DEE, despite relatively better compatibility with anode, it inevitably exhibits a fragile CEI layer on cathode side accompanied by severe ether decomposition. For NP electrolyte with strongly solvated PC, there are poor organic-rich EEIs on both electrodes, resulting from unfavorable solvation and parasitic reactions from carbonate degradation. For the integrated electrolyte combined strongly solvated PC, weakly solvated DEE and non-solvated PFPN, robust EEIs rich in F/N can be constructed on electrodes, mainly attributed to the preferential decomposition of PFPN and unique solvation configuration with modulated ion-dipole and dipole-dipole interactions through molecular anchoring effect for abundant free solvents in the dilute electrolyte. More importantly, NDPP electrolyte endows SIBs with great potential in wide-temperature applications. Discussion In conclusion, we have proposed a dipolar interaction-mediated molecular anchoring electrolyte integrated strongly solvated carbonate ester (PC), weakly solvated ether (DEE) and non-solvated PFPN for safe and durable SIBs. The electrolyte demonstrates a hierarchical solvation with abundant δ + H-δ − F, δ + H-δ − O and δ + H-δ − N dipolar interactions among PF 6 − anions and solvent molecules, especially PFPN, which activates non-coordinated PFPN and restricts free PC/DEE molecules. Multiscale experimental and theoretical investigations have manifested the integrated NDPP electrolyte enables to substantially alleviate solvent degradation at the electrodes, facilitate the construction of robust EEIs rich in F/N on both cathodes and anodes, ultimately promote comprehensive electrochemical improvements, compared with conventional ND and NP electrolytes. Particularly, the electrolyte features extraordinary electrochemical stability and reversibility. For NVPOF//Na half cells in NDPP, a significantly improved capacity retention up to 87.6% can be obtained even after 5000 cycles with enhanced CEs and EEs. Through matching with representative HC anode, the assembled NVPOF//HC full cells demonstrate prominent cycling stability. Furthermore, NDPP electrolyte is also well adaptable to commercial NVP and NT0102 cathodes, particularly, sustaining extremely stable operation of NVP cathode over a wide-temperature range from − 60 to 70 ℃. Strikingly, 95.2% of capacity retention can be observed after 900 cycles at 70 ℃, and reversible capacities of 70.2 and 51.2 mAh g − 1 can be maintained at -40 and − 60 ℃, respectively. This work involving a dipolar interaction-mediated molecular anchoring electrolyte design provides an encouraging avenue for the advancement of high-quality SIBs in extreme environments. Methods Materials NaPF 6 and DEE were purchased from DoDo Chem. PC and PFPN were purchased from Sigma-Aldrich Co., Ltd. and Shanghai Macklin Biochemical Technology Co., Ltd., respectively. The solvents were dried by the activated 4 Å molecular sieves for 72 h before use. Electrolytes were prepared in an argon-filled glovebox with O 2 and H 2 O content below 0.1 ppm. The NVPOF cathode material was prepared via a typical hydrothermal method according to our previous literature 54 . The NVP cathode materials were obtained from Youyan Technology Co., Ltd. The sodium layered oxide cathode (NT0102) were purchased from Canrd Technology Co., Ltd. The commercial HC material was purchased from Kuraray China Co., Ltd. Material characterizations Ionic conductivities of the electrolytes were determined by a portable conductivity measuring meter (DDBJ-351L, Leici). Flammability tests of the electrolytes were carried out by igniting the electrolyte-soaked glass fiber separators in the fume hood. Raman spectrum measurements were carried out to reveal the structural details and solvation environments of the salts, solvents and electrolytes. NMR (Bruker AVANCE NEO, 500 MHz) technique was applied to further analyze the solvation characteristics and intermolecular interactions of the electrolytes. Specific morphological features of the cycled electrodes were obtained through SEM (HITACHI SU8010) and HRTEM (JEOL-2100 F, 200 kV) images. Furthermore, surface and interfacial compositions of the cycled electrodes can be characterized by XPS (VG Scientific with 300 W Al Kα source) measurements. All values of binding energy were referenced to the C 1s peak of carbon located at 284.8 eV. AFM (Bruker MultiMode 8) images were also employed to further investigate the surface morphology and roughness of the cycled electrodes. TOF-SIMS (TOF.SIMS5) of the cycled electrodes was conducted to reveal the chemical compositions and distributions in detail. Electrochemical measurements The electrochemical properties of the prepared materials were characterized in the 2032-type coin cells. The NVPOF cathode containing the NVPOF material, carbon black and carboxymethyl cellulose sodium (CMC) at the weight ratio of 7:2:1 was prepared by spreading the aqueous slurry on carbon-coated Al foil as the current collector. Similarly, the NVP cathode was obtained by blending NVP power, Ketjen black and polyvinylidene fluoride (PVDF) with a weight ratio of 8:1:1 in N-methylpyrrolidone (NMP), the HC anode was prepared by mixing HC power, carbon black and PVDF at the weight ratio of 7:2:1 in NMP, and then the slurries were coated on carbon-coated Al foils. All working electrodes were dried at 100 ℃ under vacuum overnight. The active mass loading of these electrodes is in the range from 1.2 to 1.5 mg cm − 2 . For the purchased NT0102 cathode, the active mass loading is about 8 mg cm − 2 . The sodium-ion half cells are assembled in an Ar-filled glovebox. The counter electrode was the metallic Na foil. Glass filter (Whatman 934AH) was used as the separator for all batteries. GCD tests were conducted on the Neware battery test system. The sodium-ion half cells including NVPOF//Na, NT0102//Na, NVP//Na and HC//Na were investigated in a voltage range of 2-4.3, 2–4, 2.5–3.9 and 0.01-3 V (vs. Na/Na + ), respectively. The electrochemical impedance spectroscopy (EIS) was carried out with a frequency ranging from 100 kHz to 0.01 Hz and a perturbation voltage amplitude of 5 mV. LSV tests of the electrolytes were performed in the stainless steel (SS)//Na half cells with a scanning rate of 0.5 mV s − 1 . For full-cell fabrication, all HC anodes were pre-sodiated chemically, and the N/P ratio was controlled at about 1.2. The NVPOF//HC full cells were tested within a voltage window of 1.5 to 4.2 V. Computational details According to the molar ratio among the components, appropriate electrolyte boxes (15 NaPF 6 + 134 DEE, 15 NaPF 6 + 221 PC, 15 NaPF 6 + 56 DEE + 92 PC + 18 PFPN) were constructed. MD simulations of the electrolytes were carried out by using the Forcite package with COMPASS Ⅱ force field. Before conducting simulations with the NVT canonical ensemble for 50 ps lasted process, the density of each system was equilibrated with the NPT ensemble for tens of ps. The dynamic calculations were performed with a ultra-fine quality and a time step of 1 fs, and initiated with the current charges and random velocities. The DFT calculations for the salt, solvents and Na + -solvent complex molecules were conducted by using Dmol3 package with the GGA method in the form of the PBE. The atomic orbital-based double numerical plus polarization (DNP) basis set was used to describe the valence electrons. The binding energy of different Na + -solvent complex molecules were conducted by using Forcite package. The binding energy was defined as 55 : E b = E [Na−solvent] + - E Na + - E solvent where E [Na−solvent] + is the energy of the Na + -solvent complex, E solvent is the energy of the solvent molecule and E Na + is the energy of the sodium ion. Restricted to construction and selection for suitable theoretical calculation electrolyte model considering calculated accuracy and complexity simultaneously, the existence of some special solvated structure could not be excluded, whereas the major coordination environment is relatively consistent and reasonable. Declarations Competing interests The authors declare no competing interests. Data availability The authors declare that all the relevant data within this paper and its Supplementary Information file are available from the corresponding author upon request. Author contributions Y.-L.H., Z.-Y.G. and X.-L.W. conceived the idea and designed the experiments. Y.-L.H. performed the material characterizations and electrochemical measurements with assistance from Z.-Y.G., H.-H.L., X.-T.W. and S.-Y.L. J.W. contributed to the NMR tests. Y.-L.H. analyzed the data and prepared the paper with contributions from all authors. Acknowledgements We acknowledge the financial supports from the National Key Research and Development Program of China (2023YFE0202000), National Natural Science Foundation of China (no. 52173246 and 52302222), Natural Science Foundation of Jilin Province (no. 20230101128JC and 20230508177RC), Science and Technology Planning Project of Guangzhou City (2023B03J1278), China Postdoctoral Science Foundation(2023T160094), and National Postdoctoral Program for Innovative Talents (No. BX20240062). References Usiskin R , et al. Fundamentals, status and promise of sodium-based batteries. Nat Rev Mater 6 , 1020-1035 (2021). Yao A, Benson SM, Chueh WC. Critically assessing sodium-ion technology roadmaps and scenarios for techno-economic competitiveness against lithium-ion batteries. Nat Energy 10 , 404-416 (2025). Park S , et al. Obtaining V 2 (PO 4 ) 3 by sodium extraction from single-phase Na x V 2 (PO 4 ) 3 (1 < x < 3) positive electrode materials. Nat Mater 24 , 234-242 (2024). Guo Y-J , et al. Sodium layered oxide cathodes: properties, practicality and prospects. Chem Soc Rev 53 , 7828-7874 (2024). Lu X, Li S, Li Y, Wu F, Wu C, Bai Y. From Lab to Application: Challenges and Opportunities in Achieving Fast Charging with Polyanionic Cathodes for Sodium‐Ion Batteries. Adv Mater 36 , 2407359 (2024). Tang Y , et al. Sustainable layered cathode with suppressed phase transition for long-life sodium-ion batteries. Nat Sustain 7 , 348-359 (2024). Zhou R , et al. Constructing Anion Solvation Microenvironment Toward Durable High‐Voltage Sodium‐Based Batteries. Adv Mater 37 , 2416748 (2025). Xie K, Ji Y, Yang L, Pan F. Electrolyte Design Strategies to Construct Stable Cathode‐Electrolyte Interphases for High‐Voltage Sodium‐Ion Batteries. Adv Energy Mater 15 , 2405301 (2025). Zhang F , et al. Emerging Chemistry for Wide-Temperature Sodium-Ion Batteries. Chem Rev 124 , 4778-4821 (2024). Jiang L , et al. Rational design of anti-freezing electrolytes for extremely low-temperature aqueous batteries. Nat Energy 9 , 839-848 (2024). Ko S , et al. Rapid safety screening realized by accelerating rate calorimetry with lab-scale small batteries. Nat Energy , (2025). https://doi.org/10.1038/s41560-025-01751-7. Zhang J, Gai J, Song K, Chen W. Advances in electrode/electrolyte interphase for sodium-ion batteries from half cells to full cells. Cell Rep Phys Sci 3 , 100868 (2022). Zhang J , et al. Critical review on cathode electrolyte interphase towards stabilization for sodium-ion batteries. Nano Energy 128 , 109814 (2024). Zheng X , et al. Critical effects of electrolyte recipes for Li and Na metal batteries. Chem 7 , 2312-2346 (2021). Vinay B , et al. Fluorine-free electrolytes in batteries: principles, strategies, and advances. Energy Environ Sci , (2025). https://doi.org/10.1039/D4EE04820B. Meng YS, Srinivasan V, Xu K. Designing better electrolytes. Science 378 , 1065 (2022). Li Y , et al. Ether-based electrolytes for sodium ion batteries. Chem Soc Rev 51 , 4484-4536 (2022). Li C , et al. Nonaqueous Liquid Electrolytes for Sodium‐Ion Batteries: Fundamentals, Progress and Perspectives. Adv Energy Mater 13 , 2301758 (2023). Chen J, Zhang H, Fang M, Ke C, Liu S, Wang J. Design of Localized High-Concentration Electrolytes via Donor Number. ACS Energy Lett 8 , 1723-1734 (2023). Ren X , et al. Localized High-Concentration Sulfone Electrolytes for High-Efficiency Lithium-Metal Batteries. Chem 4 , 1877-1892 (2018). Zeng Z , et al. Non-flammable electrolytes with high salt-to-solvent ratios for Li-ion and Li-metal batteries. Nat Energy 3 , 674-681 (2018). Fang H , et al. Regulating Ion‐Dipole Interactions in Weakly Solvating Electrolyte towards Ultra‐Low Temperature Sodium‐Ion Batteries. Angew Chem Int Ed 63 , e202400539 (2024). Niu M , et al. Approaching fast ion transport via anion–dipole interaction in weakly solvated electrolytes enables stable Li-plating chemistry. Natl Sci Rev 12 , nwaf065 (2025). Wang C , et al. A weakly coordinating-intervention strategy for modulating Na + solvation sheathes and constructing robust interphase in sodium-metal batteries. Nat Commun 15 , 6292 (2024). Jin Y , et al. Low-solvation electrolytes for high-voltage sodium-ion batteries. Nat Energy 7 , 718-725 (2022). Wang Y , et al. Fluorine Chemistry in Rechargeable Batteries: Challenges, Progress, and Perspectives. Chem Rev 124 , 3494-3589 (2024). Chen W , et al. Hybrid solvating electrolytes for practical sodium-metal batteries. Joule 9 , 101811 (2025). Wang M, Zheng M, Lu J, You Y. High-entropy electrolyte toward battery working under extreme conditions. Joule 8 , 2467-2482 (2024). Kim SC , et al. High-entropy electrolytes for practical lithium metal batteries. Nat Energy 8 , 814-826 (2023). Zeng Y , et al. High-entropy mechanism to boost ionic conductivity. Science 378 , 1320-1324 (2022). Yang Z , et al. Modulating ion–dipole interactions in nonflammable phosphonate-based electrolyte for safe and stable sodium-ion pouch cells. Natl Sci Rev 12 , nwae466 (2025). Xu Z, Zhang X, Yang J, Cui X, Nuli Y, Wang J. High-voltage and intrinsically safe electrolytes for Li metal batteries. Nat Commun 15 , 9856 (2024). Liao Y , et al. Pentafluoro(phenoxy)cyclotriphosphazene Stabilizes Electrode/Electrolyte Interfaces for Sodium‐Ion Pouch Cells of 145 Wh Kg −1 . Adv Mater 36 , 2312287 (2024). Zhang H , et al. High-safety and high-voltage lithium metal batteries enabled by nonflammable diluted highly concentrated electrolyte. Nano Res 17 , 2638-2645 (2023). Chen J , et al. Nonflammable Succinonitrile‐Based Deep Eutectic Electrolyte for Intrinsically Safe High‐Voltage Sodium‐Ion Batteries. Adv Mater 36 , 2400169 (2024). Kelchtermans A-S , et al. Superconcentration Strategy Allows Sodium Metal Compatibility in Deep Eutectic Solvents for Sodium-Ion Batteries. ACS Omega 9 , 42343-42352 (2024). Huang Y, Zhao L, Li L, Xie M, Wu F, Chen R. Electrolytes and Electrolyte/Electrode Interfaces in Sodium‐Ion Batteries: From Scientific Research to Practical Application. Adv Mater 31 , 1808393 (2019). Qin M , et al. Rejuvenating Propylene Carbonate‐based Electrolyte Through Nonsolvating Interactions for Wide‐Temperature Li‐ions Batteries. Adv Energy Mater 12 , 2201801 (2022). Li E , et al. Hierarchical doping electrolyte solvation engineering to achieve high-performance sodium-ion batteries in wide temperature. Energy Storage Mater 73 , 103805 (2024). Chen Y , et al. Trace ethylene carbonate-mediated low-concentration ether-based electrolytes for high-voltage lithium metal batteries. Energy Environ Sci 17 , 5613-5626 (2024). Cui X , et al. 4.2 V O3‐Layered Cathodes in Sodium‐Ion Pouch Cells Enabled by an Intermolecular‐Reinforced Ether Electrolyte. Adv Mater 37 , 2415611 (2025). Wang X , et al. Anion-mediated approach to overcome oxidation in ether electrolytes for high-voltage sodium-ion batteries. Nat Commun 16 , 2536 (2025). Wu Y , et al. Electrostatic Potential as Solvent Descriptor to Enable Rational Electrolyte Design for Lithium Batteries. Adv Energy Mater 13 , 2300259 (2023). Yu Z , et al. Molecular design for electrolyte solvents enabling energy-dense and long-cycling lithium metal batteries. Nat Energy 5 , 526-533 (2020). Li N , et al. Insight into the probability of ethoxy(pentafluoro)cyclotriphosphazene (PFPN) as the functional electrolyte additive in lithium–sulfur batteries. RSC Adv 14 , 12754-12761 (2024). Yu J , et al. Regulated Li + Solvation via Competitive Coordination Mechanism of Organic Cations for High Voltage and Fast Charging Lithium Metal Batteries. Angew Chem Int Ed 64 , e202416092 (2024). Wang M , et al. Temperature-responsive solvation enabled by dipole-dipole interactions towards wide-temperature sodium-ion batteries. Nat Commun 15 , 8866 (2024). Zhao Z, Liu C, Lai T, Cui Z, Manthiram A. Macromolecule‐Enriched Solvation Enabling High‐Voltage Sodium‐Ion Batteries. Angew Chem Int Ed , e202423625 (2025). Lai P , et al. Revealing the evolution of solvation structure in low-temperature electrolytes for lithium batteries. Energy Storage Mater 67 , 103314 (2024). Feng YH , et al. Dual‐Anionic Coordination Manipulation Induces Phosphorus and Boron‐Rich Gradient Interphase Towards Stable and Safe Sodium Metal Batteries. Angew Chem Int Ed 64 , e202415644 (2024). Li Y , et al. Sole‐Solvent High‐Entropy Electrolyte Realizes Wide‐Temperature and High‐Voltage Practical Anode‐Free Sodium Pouch Cells. Adv Mater 37 , 2419764 (2025). Gao Y, Yao Y, Shi P, Huang F, Jiang Y, Yu Y. Advanced Interphases Layers for Dendrite-Free Sodium Metal Anodes. ACS Appl Mater Interfaces 17 , 17881-17894 (2025). Liu P , et al. Inorganic–Organic Hybrid Multifunctional Solid Electrolyte Interphase Layers for Dendrite‐Free Sodium Metal Anodes. Angew Chem Int Ed 62 , e202312413 (2023). Gu Z-Y , et al. Precisely controlled preparation of an advanced Na 3 V 2 (PO 4 ) 2 O 2 F cathode material for sodium ion batteries: the optimization of electrochemical properties and electrode kinetics. Inorg Chem Front 6 , 988-995 (2019). Liang H-J , et al. Electrolyte Chemistry toward Ultrawide-Temperature (−25 to 75 °C) Sodium-Ion Batteries Achieved by Phosphorus/Silicon-Synergistic Interphase Manipulation. J Am Chem Soc 146 , 7295-7304 (2024). Additional Declarations There is NO Competing Interest. Supplementary Files 48ff483308be21564f11c8993f02cef2.mp4 Video 1 68085132fa7a7bc9bccfcc1a58656c37.mp4 Video 2 c3d23533c5bb02b1be7665a3ded517bf.mp4 Video 3 supplementary.docx Dipolar interaction-mediated molecular anchoring electrolyte enables wide-temperature sodium-ion batteries with enhanced safety and durability Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6768086","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":467129849,"identity":"0a05f36e-7dea-4dde-b983-6aa977fb3c03","order_by":0,"name":"Xing-Long Wu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5UlEQVRIie3RsQqCQBjA8QvhpitXJXqHg4OrIfRVTgRbglZHQWhsNughhKD54EAXoVXIQQikocGptU6q9XQMuj98gvD9PA4B0Ol+MUNOLcf8vI+iQYTJsaPBBHwI5kMJzsfixsLKOV7i7IrAcpZyo6lVxI4nwYIVjX+qshVBICAph3OsIqaBKPa2wqflmk4REF7KEbRUBH4JSTYPSZ79RJ5CakkcbK2hJLyf2DGigBWCWWVA7QP2yV5AqiT4XJC2DYVrJn5j3UNntsvjRkm663QLXvT+Anj/3J6MVj7c/j2dTqf7214x/kXdZwA+JAAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0003-1069-9145","institution":"Northeast Normal University","correspondingAuthor":true,"prefix":"","firstName":"Xing-Long","middleName":"","lastName":"Wu","suffix":""},{"id":467129850,"identity":"a042b679-2e65-470d-920a-e5024ce182d0","order_by":1,"name":"Yong-Li Heng","email":"","orcid":"","institution":"Northeast Normal University","correspondingAuthor":false,"prefix":"","firstName":"Yong-Li","middleName":"","lastName":"Heng","suffix":""},{"id":467129851,"identity":"d1d3a722-ede9-4be8-b13b-cad09eb1a062","order_by":2,"name":"Zhen-Yi Gu","email":"","orcid":"","institution":"Northeast Normal University","correspondingAuthor":false,"prefix":"","firstName":"Zhen-Yi","middleName":"","lastName":"Gu","suffix":""},{"id":467129852,"identity":"4c7dd526-eb34-4f8c-b166-943389fdbeb9","order_by":3,"name":"Han-Hao Liu","email":"","orcid":"","institution":"Northeast Normal University","correspondingAuthor":false,"prefix":"","firstName":"Han-Hao","middleName":"","lastName":"Liu","suffix":""},{"id":467129853,"identity":"c43ffc69-490c-4565-8e6f-48b11ef4a9c4","order_by":4,"name":"Xiao-Tong Wang","email":"","orcid":"","institution":"Northeast Normal University","correspondingAuthor":false,"prefix":"","firstName":"Xiao-Tong","middleName":"","lastName":"Wang","suffix":""},{"id":467129854,"identity":"a03ab133-c967-4492-a06c-35325d969afd","order_by":5,"name":"Jie Wang","email":"","orcid":"","institution":"Northeast Normal University","correspondingAuthor":false,"prefix":"","firstName":"Jie","middleName":"","lastName":"Wang","suffix":""},{"id":467129855,"identity":"6bafaca0-dbcb-4735-aedf-bbf4056d6ee9","order_by":6,"name":"Shu-Yu Li","email":"","orcid":"","institution":"Northeast Normal University","correspondingAuthor":false,"prefix":"","firstName":"Shu-Yu","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2025-05-28 12:30:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6768086/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6768086/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":84056954,"identity":"bbfb6bee-3961-4a3b-be70-58e3ed8cd91e","added_by":"auto","created_at":"2025-06-06 09:30:54","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":382124,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePhysicochemical property studies of conventional ester and ether solvents.\u003c/strong\u003e (a) Schematic illustration of the competition between ester and ether solvents in electrolyte design. (b) Basic physicochemical properties and (c) ESP distribution of representative solvents. (d) Comparative analysis of PC and DEE.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/7aa7eacd77ffc034929689fe.png"},{"id":84057906,"identity":"c2c8a8a5-9258-4621-be10-8cbc1fca7b43","added_by":"auto","created_at":"2025-06-06 09:38:55","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":502365,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDesign concept of dipolar interaction-mediated molecular anchoring electrolyte.\u003c/strong\u003e (a) Comparison among conventional dilute electrolytes with weakly solvated ethers, strongly solvated esters, and integrated solvating electrolytes combined with strong, weak and non-solvated solvents. (b) Schematic diagram of the features of PFPN. (c) Ionic conductivity of the electrolytes at 25 ℃. (d, e) Electrochemical oxidation and reduction stability of different electrolytes as evaluated by LSV measurements at 0.5 mV s\u003csup\u003e-1\u003c/sup\u003e. (f) Flammability tests of the electrolytes.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/1562fd300bd3e90fd6168e8f.png"},{"id":84057904,"identity":"f2d3ae5f-e744-4b91-b1bf-6d572004439b","added_by":"auto","created_at":"2025-06-06 09:38:54","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":306454,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDecryption of intricate dipolar interactions in electrolytes.\u003c/strong\u003e (a) Raman spectra of various electrolyte components. (b) \u003csup\u003e19\u003c/sup\u003eF NMR spectra of electrolytes. (c) 2 D \u003csup\u003e1\u003c/sup\u003eH-\u003csup\u003e19\u003c/sup\u003eF HOESY NMR spectra of NDPP electrolyte. (d) Matrix diagram of intermolecular interactions among various electrolyte components. (e) Evolution of interactions with optimized structures of different complexes. Dashed lines show possible interacting atoms, like δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e-\u003c/sup\u003eF, δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e-\u003c/sup\u003eO and δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e-\u003c/sup\u003eN. Colors of elements: H, white; C, grey; N, blue; O, red; F, cyan; P, light pink.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/3fa6e7e6115d08d68638b5dd.png"},{"id":84056958,"identity":"d60a5bf2-7ef6-447f-8bbf-d8754c82cc97","added_by":"auto","created_at":"2025-06-06 09:30:55","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":657826,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eAnalysis of solvation configurations in electrolytes.\u003c/strong\u003e (a-c) Snapshots of MD simulation cells and representative solvation structures with ESP distributions for (a) ND, (b) NP and (c) NDPP. (d-f) Calculated RDFs and (g) CNs of three electrolyte systems. (h) Schematic diagram of the interaction relationship among Na\u003csup\u003e+\u003c/sup\u003e, solvents and anion in NDPP electrolyte.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/cf022d25a79362f94baa884d.png"},{"id":84056963,"identity":"a850fbec-eda7-4056-8a17-1c3e8a94a430","added_by":"auto","created_at":"2025-06-06 09:30:55","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":307884,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eEvaluation of electrochemical investigations.\u003c/strong\u003e (a) The first GCD profiles of NVPOF//Na half cells with different electrolytes. Insets are obtained ICE and IEE. (b) Cycling stability of NVPOF//Na half cells. (c) Evolution of EE during the cycle. Inset is GCD curves for NDPP. (d) Radar plot evaluating the three electrolytes. (e) Cycling performance of NT0102//Na half cells with NDPP electrolyte. (f) Cycling stability of NVP//Na half cells at high temperatures. Insets are their capacity retentions. (g) GCD curves of NVP//Na half cells at low temperatures.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/24c45d3c13fa445b584c638c.png"},{"id":84057907,"identity":"85ad13a4-4681-4232-80d5-3e3faadcc9ac","added_by":"auto","created_at":"2025-06-06 09:38:55","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":578035,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eInterfacial chemistry investigations with different electrolytes.\u003c/strong\u003e (a) HRTEM images with white dashed lines to outline CEI layers on cycled NVPOF cathodes after 50 cycles at 0.5 C and RT. (b) XPS spectra of C 1s, O 1s and F 1s, (c) AFM surface roughness and 3 D topography analysis of cycled NVPOF cathodes. TOF-SIMS (d) 2 D and (e) 3 D spatial distribution of selected secondary ion fragments in the CEI on cycled NVPOF cathode with NDPP. (f) HOMO/LUMO energy levels of solvents, Na\u003csup\u003e+\u003c/sup\u003e-solvent and Na\u003csup\u003e+\u003c/sup\u003e-solvent-anion complexes.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/d7417bb5f828becb90bed211.png"},{"id":84056972,"identity":"218cbc6c-5fb5-408a-8383-9df520bbc017","added_by":"auto","created_at":"2025-06-06 09:30:55","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":631323,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSchematic diagram of comprehensive assessment of different electrolytes in SIBs.\u003c/strong\u003e (a) ND. (b) NP. (c) NDPP.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/b22dabdd16c975c4037f0173.png"},{"id":85890729,"identity":"90215637-ce33-426b-b22c-530e78d9daab","added_by":"auto","created_at":"2025-07-02 19:28:47","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4488572,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/128ba504-6208-46c2-8174-9a1a7f1cbfd9.pdf"},{"id":84057909,"identity":"ae6b77ae-1127-4575-a6e4-65bf7a40eb7b","added_by":"auto","created_at":"2025-06-06 09:38:55","extension":"mp4","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":4438726,"visible":true,"origin":"","legend":"\u003cp\u003eVideo 1\u003c/p\u003e","description":"","filename":"48ff483308be21564f11c8993f02cef2.mp4","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/e5b97bbea36f63f354f44248.mp4"},{"id":84056967,"identity":"291c3489-de0e-470f-bba6-79b3187cb3ee","added_by":"auto","created_at":"2025-06-06 09:30:55","extension":"mp4","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":2433278,"visible":true,"origin":"","legend":"Video 2","description":"","filename":"68085132fa7a7bc9bccfcc1a58656c37.mp4","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/4c9e57a36727c21b3dad4876.mp4"},{"id":84056959,"identity":"154f768b-53f2-41a8-be86-52c975489c06","added_by":"auto","created_at":"2025-06-06 09:30:55","extension":"mp4","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":2198810,"visible":true,"origin":"","legend":"Video 3","description":"","filename":"c3d23533c5bb02b1be7665a3ded517bf.mp4","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/9d7147365448ad565f27196a.mp4"},{"id":84056980,"identity":"510d833f-ef24-4e22-af56-600f40421105","added_by":"auto","created_at":"2025-06-06 09:30:55","extension":"docx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":15294921,"visible":true,"origin":"","legend":"Dipolar interaction-mediated molecular anchoring electrolyte enables wide-temperature sodium-ion batteries with enhanced safety and durability","description":"","filename":"supplementary.docx","url":"https://assets-eu.researchsquare.com/files/rs-6768086/v1/7b615f52b4c49e525bdae15a.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Dipolar interaction-mediated molecular anchoring electrolyte enables wide-temperature sodium-ion batteries with enhanced safety and durability","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSIBs are emerging as ideal candidates for next-generation large-scale energy storage technologies due to their significant resource advantages, environmental friendliness and potential economic benefits\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. Unfortunately, despite tremendous breakthroughs in electrode materials like layered oxides and polyanionic compounds\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e, the commercialization of SIBs remains constrained by two critical technical bottlenecks: (i) under high-voltage conditions (\u0026gt;\u0026thinsp;4.2 V), electrochemical durability and interfacial compatibility with highly reactive electrodes is insufficient for conventional electrolyte systems, causing limited lifespan\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e; (ii) in extreme temperature environments (\u0026lt; -40\u0026deg;C or \u0026gt;\u0026thinsp;60\u0026deg;C), sharp decline in ionic conductivity of electrolytes and exacerbation of interfacial parasitic reactions accelerate battery failure\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e, severely restricting their application in special scenarios (e.g., polar exploration, aerospace). Particularly, safety concerns should not be underestimated for battery sustainability\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e. The essence of these problems lies in multiscale failure mechanisms of conventional electrolytes: at the molecular level, thermodynamic instability of solvation structures causes uncontrolled oxidation decomposition kinetics at high voltages; from an interfacial perspective, insufficient mechanical strength and chemical inertness of electrode-electrolyte interphases (EEIs) fail to suppress mechanical fracture and parasitic reaction penetration during cycling\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. Existing research faces trade-off dilemmas, including energy density reduction (e.g., capacity loss in cathodes caused by high-salt systems) or process economic efficiency deterioration (e.g., skyrocketing costs of fluorinated solvents)\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e. How to achieve multiscale synergistic optimization in electrolyte solvation, interfacial mechanics and electrochemical stability remains a key scientific challenge for practical application of SIBs.\u003c/p\u003e \u003cp\u003eElectrolytes, serving as the \u0026ldquo;ion transport hub\u0026rdquo; of batteries, profoundly affect electrochemical properties and interfacial chemistry through their solvation structures\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e, modulated by intermolecular interactions (ion-ion, ion-dipole and dipole-dipole). In conventional carbonate (e.g., EC, PC) and ether-based (e.g., DME, G2) electrolytes, strong cation-dipole interactions predominantly promote the formation of solvent-separated ion pairs (SSIPs), facilitating salt dissociation and high ionic conductivity\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e. Unfavorably, they bring about vulnerable EEIs rich in organic components, which tend to rupture and fail under cyclic stress. Additionally, excessive free solvents undergo persistent parasitic reactions at the interfaces during the cycle, thus drastic electrochemical deterioration occurs. To address this dilemma, solvation engineering has made critical breakthroughs: except for prevalent (localized) high-concentration electrolytes with enhanced anion coordination to form inorganic-rich EEIs\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e, emerging weakly solvating electrolytes with reduced cation-dipole interactions enable contact ion pairs (CIPs) and aggregates (AGGs) to accumulate and dominate\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e, constructing high-modulus EEIs. Nevertheless, these approaches are plagued by low salt solubility, high viscosity and excessive fluoride dependence\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. Lately, hybrid strongly and weakly solvating electrolytes (e.g., THF/DMTMSA\u003csup\u003e27\u003c/sup\u003e) allow for synchronous optimization in both cathodes and Na metal anode by regulating ion-dipole interactions and solvation configurations. Furthermore, entropy regulation effects have been introduced into electrolyte design, leveraging configurational entropy to inhibit solvent crystallization, demonstrating great promise for applications under extreme conditions\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e. Nonetheless, relevant research remains in its infancy, extensive exploration is required. Additionally, considering persistent safety concerns, abundant flame-retardant systems including phosphates\u003csup\u003e\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e, fluorinated phosphazenes\u003csup\u003e\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u003c/sup\u003e, and ionic liquids are discovered to reduce self-extinguishing times but bring about new issues like high viscosity, poor wettability and incompatibility with anodes\u003csup\u003e\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e. The current core challenge lies in balancing conflicting parameters such as ionic conductivity, interfacial stability, cost and environmental friendliness, which necessitates persistent rational design and exploration.\u003c/p\u003e \u003cp\u003eHerein, we conducted a comprehensive analysis of prevalent carbonate and ether-based solvents to further elucidate their intrinsically complementary characteristics. On this basis, a dipolar interaction-mediated molecular anchoring electrolyte engineering was conceived to integrate strongly solvating ester (PC), weakly solvating ether (DEE) and anti-solvent (PFPN) for safe and durable SIBs under extreme conditions. Particularly, not only anion-dipole interactions via δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e\u0026minus;\u003c/sup\u003eF between PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e and PC or PFPN but also dipole-dipole interactions via δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e\u0026minus;\u003c/sup\u003eO and δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e\u0026minus;\u003c/sup\u003eN between PC and PFPN have been deciphered through spectroscopic and theoretical investigations, effectively activating PFPN anti-solvent and restricting free PC/DEE molecules by anchoring effect from PFPN. Through modulating dipolar interactions, the electrolyte enables great compatibility with both anodes and high-voltage cathodes, accompanied by construction of robust EEIs rich in F/N. Consequently, representative high-voltage phosphates, layered oxide cathodes and hard carbon (HC) anode demonstrate extraordinary cycling stability, e.g., 87.6% of reversible capacity after 5000 cycles for Na\u003csub\u003e3\u003c/sub\u003eV\u003csub\u003e2\u003c/sub\u003e(PO\u003csub\u003e4\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003eF (NVPOF) model cathode. Conspicuously, the electrolyte also sustains successful operation under wide temperatures (-60\u0026thinsp;~\u0026thinsp;70 ℃) with admirable capacity retention of 95.2% over 900 cycles at 70 ℃ and 51.2 mAh g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e of reversible capacity at -60 ℃ for Na\u003csub\u003e3\u003c/sub\u003eV\u003csub\u003e2\u003c/sub\u003e(PO\u003csub\u003e4\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e (NVP). This work reveals a dipolar interaction-mediated solvation-interface synergistic stabilization mechanism and establishes a \u0026ldquo;molecular anchoring-solvation configuration-interfacial dynamics\u0026rdquo; structure-property relationship, providing new insights into the advancement of safe and durable electrochemical systems under extreme conditions like polar exploration and deep space missions.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eComparative analysis of prevalent carbonates and ethers\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere is a trade-off between conventional carbonate and ether-based solvents from the perspective of electrolyte design. Integrated electrolyte engineering has attracted great attention due to their promise of comprehensive electrochemical properties, especially the following critical aspects: battery lifespan, energy efficiency, cost effectiveness and safety concerns (\u003cstrong\u003eFig. 1a\u003c/strong\u003e). Careful selection of sodium salts, solvents and additives is essential to electrochemical properties. Generally, NaPF\u003csub\u003e6\u003c/sub\u003e is deemed as an ideal sodium salt when taking solubility, conductivity, chemical/thermal stability, toxicity and corrosive nature into account together, compared to other sodium salts like NaBF\u003csub\u003e4\u003c/sub\u003e, NaClO\u003csub\u003e4\u003c/sub\u003e, NaOTf and NaFSI\u003csup\u003e37\u003c/sup\u003e. Furthermore, it is recognized that carbonates and ethers constitute two primary solvent systems in SIBs that have been extensively investigated. Basic physicochemical properties of representative carbonate and ether solvent molecules have been summarized in \u003cstrong\u003eFig. 1b\u003c/strong\u003e and \u003cstrong\u003eSupplementary Table\u003c/strong\u003e\u003cstrong\u003es 1\u003c/strong\u003e, \u003cstrong\u003e2\u003c/strong\u003e. Cyclic carbonates like EC and PC exhibit the dielectric constants far greater than those of other solvents, indicating high solvation ability and ionic conductivity. Among them, PC possesses the widest liquid range with low melting point (-48.8 ℃) and high boiling point (242 ℃), conducive to sustaining a wide service temperature range of batteries\u003csup\u003e38, 39\u003c/sup\u003e. EC is solid with 36.3 ℃ of melting point and difficult to use alone\u003csup\u003e40\u003c/sup\u003e. Generally, ethers exhibit low melting and boiling points, especially THF and MeTHF, which are volatile and prone to oxidation\u003csup\u003e41, 42\u003c/sup\u003e. DEE demonstrates a moderate melting and boiling point (-74 and 121 ℃, respectively). In addition, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of these solvents are calculated based on density functional theory (DFT) to determine their oxidation and reduction properties (\u003cstrong\u003eSupplementary Fig. 1\u003c/strong\u003e). Generally, carbonates have significantly lower HOMO\u0026nbsp;levels, indicating higher oxidation stability and thus excellent compatibility with high-voltage cathodes. Meanwhile, their lower LUMO levels imply inferior reduction stability and thus poor compatibility with anode. In contrast to carbonates, ethers demonstrate higher HOMO and LUMO energy levels, manifesting worse oxidation stability while better reduction stability. Binding energy calculations with optimized structures for various Na\u003csup\u003e+\u003c/sup\u003e-solvent complexes are conducted, as depicted in \u003cstrong\u003eSupplementary Fig. 2\u003c/strong\u003e, where EC, PC and DME possess significantly lower binding energy with Na\u003csup\u003e+\u003c/sup\u003e while G2 and DEE exhibit the higher values. Furthermore, for rational electrolyte design, electrostatic potential (ESP) analysis of these solvent molecules is demonstrated in \u003cstrong\u003eFig. 1c\u003c/strong\u003e, which is a crucial descriptor to further elucidate interactions between Na\u003csup\u003e+\u003c/sup\u003e and solvents\u003csup\u003e43, 44\u003c/sup\u003e. Their negative charges are mainly localized at oxygen atoms, which are prone to coordinate with Na\u003csup\u003e+\u003c/sup\u003e. Among them, strong polar PC exhibits a minimum ESP\u003csub\u003emin\u003c/sub\u003e with |ESP\u003csub\u003emin\u003c/sub\u003e| \u0026gt; ESP\u003csub\u003emax\u003c/sub\u003e, implying strong coordination ability. While DEE molecule shows less negative ESP\u003csub\u003emin\u003c/sub\u003e and significantly decreased ESP\u003csub\u003emax\u003c/sub\u003e, accompanied by more uniformly distributed electron density, indicating decreased Na\u003csup\u003e+\u003c/sup\u003e solvation power. Based on above considerations, PC and DEE with significantly complementary characteristics are selected to function synergistically as solvents in pursuit of integrated electrolyte design (\u003cstrong\u003eFig. 1d\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDesign logic of integrated solvating electrolyte\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNote that simple blending of PC and DEE is difficult to achieve desired properties and cannot make full use of their advantages (\u003cstrong\u003eSupplementary Fig. 3\u003c/strong\u003e). More importantly, conventional carbonate and ether solvents are volatile and combustible, posing a serious threat to battery safety. Consequently, PFPN is introduced into the integrated electrolyte system to leverage its prominent advantages as follows. Primarily, based on synergistic effect of the condensed phase flame retardant mechanism and free radical trapping mechanism\u003csup\u003e45\u003c/sup\u003e, PFPN is deemed as an excellent flame retardant on account of abundance of F, N and P elements, as detailed in \u003cstrong\u003eFig. 2b\u003c/strong\u003e. On the one hand, PFPN can form a dense and sturdy carbon layer when subjected to high temperatures, effectively isolating oxygen. On the other hand, fluorine, nitrogen and phosphorus free radicals ([F]∙, [N]∙ and [P]∙) produced by PFPN can trap active free radicals (such as H∙ and HO∙) in the combustion chain reaction, thereby interrupting the combustion process. Additionally, PFPN decomposition can produce non-flammable gases like N\u003csub\u003e2\u003c/sub\u003e and NH\u003csub\u003e3\u003c/sub\u003e, which dilutes the concentration of combustible gas and reduces the combustion intensity. Besides, PFPN exhibits reduced HOMO and LUMO energy levels compared to those of conventional carbonates and ethers, demonstrating its outstanding antioxidant capacity and preferentially involved in SEI formation. Furthermore, ESP analysis of PFPN is performed to elucidate the charge distribution. It can be found that PFPN exhibits a significantly higher ESP\u003csub\u003emin\u003c/sub\u003e and the |ESP\u003csub\u003emin\u003c/sub\u003e| is much lower than ESP\u003csub\u003emax\u003c/sub\u003e, indicating its non-solvation property. Nevertheless, it can regulate solvation structure through intermolecular dipolar interactions and a unique anchoring effect has been proposed, which will be elaborated in the following sections.\u003c/p\u003e\n\u003cp\u003eIn view of above factors, an integrated solvating electrolyte was formulated with 0.8 M NaPF\u003csub\u003e6\u003c/sub\u003e dissolved in weakly solvated DEE, strongly solvated PC and non-solvated PFPN, denoted as NDPP (\u003cstrong\u003eSupplementary Table 3\u003c/strong\u003e). Additionally, two control electrolytes have also been proposed, namely ND\u0026nbsp;(0.8 M NaPF\u003csub\u003e6\u003c/sub\u003e in DEE) and NP (0.8 M NaPF\u003csub\u003e6\u003c/sub\u003e in PC). As illustrated in \u003cstrong\u003eFig. 2a\u003c/strong\u003e, it is anticipated that the developed NDPP electrolyte has several remarkable characteristics with nonflammability, intricate intermolecular interactions and good compatibility with cathode and anode, in sharp contrast to ND and NP electrolytes. Furthermore, ionic conductivity of ND, NP and NDPP electrolytes is 1.31, 5.73 and 5.81 mS cm\u003csup\u003e-1\u003c/sup\u003e, respectively, as displayed in \u003cstrong\u003eFig. 2c\u003c/strong\u003e. The ND electrolyte displays an extremely low ionic conductivity due to weak solvation of DEE. Additionally, oxidation/reduction stability of different electrolytes have also been evaluated via linear sweep voltammetry (LSV) measurements (\u003cstrong\u003eFig. 2d, e\u003c/strong\u003e). As expected, NDPP electrolyte exhibits not only enhanced anti-oxidative capacity (up to 4.85 V) but also prominent reduction stability due to the synergy effect involved in PFPN, verifying the effectiveness of PFPN in enhancing redox stability and thus compatibility with both high-voltage cathodes and anodes. Remarkably, NDP electrolyte obtained by simply blending PC and DEE still shows unsatisfactory redox stability, which substantiates the indispensable role of PFPN. This result can also be further confirmed by the following electrochemical investigations. Moreover, flammability tests of electrolytes are displayed in \u003cstrong\u003eFig. 2f\u0026nbsp;\u003c/strong\u003eand \u003cstrong\u003eSupplementary Videos 1-3\u003c/strong\u003e. Predictably, NDPP electrolyte demonstrates inherently non-flammable properties, attributed to the introduction of flame-retardant PFPN. Whereas ND and NP electrolytes are obviously flammable, leading to serious security concerns.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDecipherment of dipole interactions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGenerally, intricate intermolecular interplay involving ion-ion, ion-dipole and dipole-dipole interactions are present in the electrolytes, demonstrating a crucial role in manipulating solvation and interfacial chemistry\u003csup\u003e46, 47\u003c/sup\u003e. To comprehensively understand these interactions, extensive spectral and theoretical investigations were conducted. Raman analysis of salt, solvents and electrolytes were executed to identify intermolecular interactions among various electrolyte components (\u003cstrong\u003eFig. 3a\u003c/strong\u003e). Notably, there is a strong peak at 728.1 cm\u003csup\u003e-1\u003c/sup\u003e in NDPP, assigned to PFPN. Meanwhile, this peak exhibits a red shift compared to pure PFPN solvent, indicating the presence of interactions between PFPN and other electrolyte components (e. g., PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e, PC and DEE). Furthermore, for ND, NP and NDPP electrolytes, the peak appears at 729~744 cm\u003csup\u003e-1\u003c/sup\u003e can be attributed to coordinated PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e. Additionally, the coordinated DEE and PC can be observed in ND, NP and NDPP electrolytes. More evidence for the changes in interactions can be elucidated by nuclear magnetic resonance (NMR) investigations. \u003cstrong\u003eFig. 3b\u003c/strong\u003e presents \u003csup\u003e19\u003c/sup\u003eF NMR spectra of different electrolytes. From ND, NDPP to NP, P-F peaks in PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e shift upfield, which stems from an increase in electron cloud density around F, manifesting the reduced interaction between Na\u003csup\u003e+\u003c/sup\u003e and PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e in NP electrolyte. To gain deep insights into intricate interactions in\u0026nbsp; NDPP electrolyte, we employed a 2 D \u003csup\u003e1\u003c/sup\u003eH-\u003csup\u003e19\u003c/sup\u003eF heteronuclear overhauser effect spectroscopy (HOESY) study\u003csup\u003e48, 49\u003c/sup\u003e. As delineated in \u003cstrong\u003eFig. 3c\u003c/strong\u003e, several distinct cross signals indicate the interactions between PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e anions and PC or PFPN solvents through \u0026delta;\u003csup\u003e+\u003c/sup\u003eH-\u0026delta;\u003csup\u003e-\u003c/sup\u003eF. Note that existence of the interactions between PFPN molecules can also be observed. Furthermore, interactions among various electrolyte components can be in-depth investigated through theoretical calculations. \u003cstrong\u003eFig. 3d\u003c/strong\u003e and \u003cstrong\u003ee\u003c/strong\u003e demonstrate their binding energy calculations with the corresponding optimized structures. Among them, there are relatively strong interactions between PC and PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e through \u0026delta;\u003csup\u003e+\u003c/sup\u003eH-\u0026delta;\u003csup\u003e-\u003c/sup\u003eF, moderate interactions between PFPN and other electrolyte components (DEE, PC and PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e) through \u0026delta;\u003csup\u003e+\u003c/sup\u003eH-\u0026delta;\u003csup\u003e-\u003c/sup\u003eF, \u0026delta;\u003csup\u003e+\u003c/sup\u003eH-\u0026delta;\u003csup\u003e-\u003c/sup\u003eO and \u0026delta;\u003csup\u003e+\u003c/sup\u003eH-\u0026delta;\u003csup\u003e-\u003c/sup\u003eN. Consequently, non-coordinated PFPN in NDPP can be activated via dipolar interactions with vulnerable PC and DEE can be anchored, which ameliorates the solvation environment and interfacial chemistry, conductive to electrochemical improvements. Note that the interactions between Na\u003csup\u003e+\u003c/sup\u003e cation and other compositions, especially PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e anion are significantly stronger through the coordination between Na\u003csup\u003e+\u003c/sup\u003e and O/N/F atoms (\u003cstrong\u003eSupplementary Fig. 4\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIdentification of electrolyte solvation structures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo shed light on the evolution of Na\u003csup\u003e+\u003c/sup\u003e solvation structure, classic molecular dynamics (MD) simulations of different electrolyte systems were implemented and snapshots are illustrated in \u003cstrong\u003eFig. 4a-c\u003c/strong\u003e. Particularly, their representative solvation configurations with electron distribution through ESP analysis are presented to further elucidate the fundamental ion-solvent chemistry. In these Na\u003csup\u003e+\u003c/sup\u003e-anion-solvent complexes, negative charges are mainly contributed on the surface of PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e anions. Additionally, for NP and NDPP electrolytes, stronger affinity between PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e and PC engenders electron delocalization in the complexes, leading to more scattered charge distribution compared to that in ND electrolyte. More detailed information about Na\u003csup\u003e+\u003c/sup\u003e solvation structures can be obtained by further analysis of radial distribution functions (RDFs) and the corresponding coordination numbers (CNs) from MD simulations, as displayed in \u003cstrong\u003eFig. 4d-g\u003c/strong\u003e. In ND electrolyte, an initial peak corresponding to Na\u003csup\u003e+\u003c/sup\u003e-O(DEE) species appears at approximately 2.27 \u0026Aring; while that of Na\u003csup\u003e+\u003c/sup\u003e-F(PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e) is located at 2.23 \u0026Aring;. Also, their CN values are calculated as 3.61 and 2.43, respectively. This result may be attributed to weak solvation capability of DEE and thus lead to the formation of anion-derived EEIs, consistent with previous literature. While in NP electrolyte, initial peaks of Na\u003csup\u003e+\u003c/sup\u003e-O(PC) and Na\u003csup\u003e+\u003c/sup\u003e-F(PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e) are observed at 2.28 and 2.18 \u0026Aring;, respectively, and the corresponding CN of PC is up to 4.48 but that of F in PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e is only 1.77. Consequently, such a significant difference in CN drives the generation of PC derived organic-dominated EEIs. This phenomenon is in agreement with strong coordination capability of PC with Na\u003csup\u003e+\u003c/sup\u003e. Furthermore, for the integrated NDPP electrolyte, initial peaks of Na\u003csup\u003e+\u003c/sup\u003e-O(PC), Na\u003csup\u003e+\u003c/sup\u003e-O(DEE) and Na\u003csup\u003e+\u003c/sup\u003e-F(PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e) are identified at 2.23, 2.32 and 2.18 \u0026Aring; with CN values of 2.98, 1.61 and 1.68, respectively, indicating competitive coordination of these solvents/anions, which facilitates the formation of hybrid inorganic/organic coupling EEIs. Notably, more Na\u003csup\u003e+\u003c/sup\u003e-solvent complexes are conducive to enhancing antioxidant capacity of solvent molecules particularly PC and DEE. Meanwhile, there is a negligible initial peak of Na\u003csup\u003e+\u003c/sup\u003e-N(PFPN), implying that PFPN essentially does not coordinate with Na\u003csup\u003e+\u003c/sup\u003e. Nevertheless, as aforementioned, the existence of dipolar interactions between PFPN and other solvents/anions can activate the anti-solvent, undoubtedly having a certain impact on the holistic solvation environment. As illustrated in \u003cstrong\u003eFig. 4h\u003c/strong\u003e, intricate interaction relationship among Na\u003csup\u003e+\u003c/sup\u003e, solvents and anion in NDPP electrolyte is distinctly demonstrated. Particularly, the coordinate bond generally exists between Na\u003csup\u003e+\u003c/sup\u003e cation and PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e anion. In addition, electrostatic interactions including ion-dipole and dipole-dipole are present between electrolyte components (e. g., \u0026delta;\u003csup\u003e-\u003c/sup\u003eF in PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e and \u0026delta;\u003csup\u003e+\u003c/sup\u003eH in PC or PFPN), as mentioned earlier in \u003cstrong\u003eFig. 3\u003c/strong\u003e. These findings confirm the variations in interactions and solvation configurations from weakly solvated ND and strongly solvated NP to integrated solvating NDPP electrolytes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEvaluation of electrochemical properties\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe proceeded to evaluate the developed electrolytes for long-term electrochemical durability of representative cathodes (e. g., NVPOF, NVP and NT0102) and HC anodes. Initially, \u003cstrong\u003eFig. 5a\u003c/strong\u003e demonstrates the first galvanostatic charge-discharge (GCD) profiles of NVPOF//Na half cells with different electrolytes at 0.1 C and room temperature (RT). Compared with ND and NP, the integrated NDPP electrolyte allows for the optimal electrochemical behavior in terms of discharge specific capacity (from 118.07, 118.58 to 123.80 mAh g\u003csup\u003e-1\u003c/sup\u003e), initial CE (from 80.56%, 77.27% to 92.39%) and EE (from 79.78%, 75.41% to 90.32%). Furthermore, their cycling stability was investigated at 2 C and RT (\u003cstrong\u003eFig. 5b\u003c/strong\u003e). Remarkably, the NVPOF cathode in NDPP sustains 87.6% of capacity retention even after 5000 cycles, along with persistently stable CEs. In sharp contrast, there are significant capacity attenuation for NVPOF//Na half cells with ND and NP electrolytes, accompanied by 75.6% and 81.6% of capacity only after 450 cycles, respectively. Meanwhile, GCD curves after different cycles are disclosed in \u003cstrong\u003eFig. 5c\u003c/strong\u003e and \u003cstrong\u003eSupplementary Fig. 5\u003c/strong\u003e, indicating a more stable voltage polarization phenomenon in NDPP electrolyte. Additionally, evolution of EE during the cycle can be discovered, which further highlights the reliability of NDPP electrolyte. Overall, the integrated electrolyte has demonstrated significant advantages from the following perspectives: ionic conductivity, oxidation stability, reduction stability, electrochemical durability and safety, compared with ND and NP electrolytes (\u003cstrong\u003eFig. 5d\u003c/strong\u003e). Moreover, cycling stability was also tested when commercial sodium nickel iron manganese oxide (NT0102) was applied as the cathode in SIBs. NT0102//Na half cells coupled with NDPP electrolyte are capable of maintaining steady operation for 350 cycles at 1 C with 80.5% of capacity retention, as shown in \u003cstrong\u003eFig. 5e\u003c/strong\u003e. Additionally, NVP is also employed as a model cathode, aiming to further determine the universality of NDPP electrolyte (\u003cstrong\u003eSupplementary Fig. 6\u003c/strong\u003e). Remarkably, there is no capacity decline for NVP//Na half cells during 2500 cycles at 10 C and RT, delivering ~93 mAh g\u003csup\u003e-1\u003c/sup\u003e of reversible capacity.\u003c/p\u003e\n\u003cp\u003eMore importantly, practical feasibility of the integrated NDPP electrolyte under extreme conditions (particularly wide temperatures) was further demonstrated. Initially, the formulated NDPP electrolyte not only remains liquid without salt precipitation after storage at -60 ℃, but also still demonstrates good chemical stability at 60 ℃, as shown in \u003cstrong\u003eSupplementary Fig. 7\u003c/strong\u003e. As expected, NVPOF//Na half cells with NDPP electrolyte display excellent cycling stability at 5 C and high temperatures, with 92.4% of capacity retention after 1500 cycles at 50 ℃ and 90.8% after 500 cycles at 60 ℃ (\u003cstrong\u003eSupplementary Fig. 8\u003c/strong\u003e). Their GCD curves at different cycles are demonstrated in \u003cstrong\u003eSupplementary Fig. 9a\u0026nbsp;\u003c/strong\u003eand\u003cstrong\u003e\u0026nbsp;b\u003c/strong\u003e, indicating stable and reversible electrochemical behaviors at high temperatures. When the temperature rises further to 70 ℃, the NVPOF cathode exhibits a significantly irreversible process when charging and thus low CE (\u003cstrong\u003eSupplementary Fig. 9c\u003c/strong\u003e), triggered by severe oxidative decomposition of the electrolyte and side reactions between cathode and electrolyte. Nevertheless, inferior low-temperature performance can be observed for NVPOF//Na half cells with NDPP electrolyte at -25 and -40 ℃ (\u003cstrong\u003eSupplementary Fig. 10\u003c/strong\u003e), which may be attributed to restricted electronic and ionic conductivities from NVPOF material. Additionally, electrochemical investigations of NVP cathode at different temperatures were also carried out to further evaluate the wide-temperature adaptability of NDPP electrolyte.\u003cstrong\u003e\u0026nbsp;Supplementary Fig. 11\u003c/strong\u003e and \u003cstrong\u003eFig. 5f\u003c/strong\u003e demonstrate its typical GCD curves and remarkable cycling stability at high temperatures, specifically, NVP//Na half cells exhibit 95.2% and 94.2% of capacity retentions after 1000 cycles at 50 and 60 ℃, respectively. Even at 70 ℃, 95.2% of capacity can be maintained after 900 cycles. For low-temperature research, unlike NVPOF, NVP cathode is employed due to its relatively higher electronic conductivity. As expected, NVP//Na half cells with NDPP electrolyte deliver superior electrochemical properties at -40 and -60 ℃ (\u003cstrong\u003eFig. 5g\u003c/strong\u003e), with 70.2 and 51.2 mAh g\u003csup\u003e-1\u003c/sup\u003e of reversible capacity at 0.1 C, respectively. Furthermore, remarkable cycling stability can also be identified, as shown in \u003cstrong\u003eSupplementary Fig. 12\u003c/strong\u003e. These investigations have forcefully proved the feasibility of stable operation of NDPP electrolyte for different cathodes even under wide temperatures.\u003c/p\u003e\n\u003cp\u003eIn addition to being compatible with various cathodes in SIBs, electrolyte must also cater to the anodes to achieve practical application of full cells. \u003cstrong\u003eSupplementary Fig. 1\u003c/strong\u003e\u003cstrong\u003e3\u003c/strong\u003e is typical GCD profiles of HC anodes in different electrolytes. As expected, HC//Na half cell with NDPP demonstrates a moderate reversible capacity close to 320 mAh g\u003csup\u003e-1\u003c/sup\u003e at 25 mA g\u003csup\u003e-1\u003c/sup\u003e compared to those of ND and NP electrolytes. Furthermore, their electrochemical stability tests were also conducted (\u003cstrong\u003eSupplementary Fig. 14\u003c/strong\u003e). The integrated NDPP electrolyte is conducive to excellent cycling stability. Based on above findings, a representative NVPOF//HC full cell was assembled and its electrochemical properties were investigated, as demonstrated in \u003cstrong\u003eSupplementary Fig. 15\u003c/strong\u003e. It delivers a high initial specific capacity of 119.7 mAh g\u003csup\u003e-1\u003c/sup\u003e accompanied by a CE of 90.33% at 0.1 C and cycling stability with 79.1% of capacity retention after 1000 cycles at 2 C.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMultiscale analysis of interfacial chemistry\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInterfacial stability plays a crucial role in electrochemical improvement. To evaluate interfacial effects on cathode and anode after cycling in different electrolyte systems, surface morphology of the cycled NVPOF and HC in various electrolytes were characterized by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) techniques, as displayed in \u003cstrong\u003eFig. 6a\u003c/strong\u003e and \u003cstrong\u003eSupplementary Figs. 16-18\u003c/strong\u003e. Remarkably, the NVPOF cathode cycled in NDPP electrolyte appears intact without visible fissures. Simultaneously, a thin, compact and smooth CEI layer can be observed with a thickness of only 3.3 nm. These manifest harmful side reactions between cathode and electrolyte are effectively suppressed. Contrastingly, there are disrupted morphologies and significant microcracks, with thick and nonuniform CEI layers on NVPOF cathodes cycled in ND and NP, which are responsible for their poor CE and electrochemical stability. For HC anode, when cycling in ND electrolyte, it exhibits better surface morphology with a thinner SEI layer (15.5 nm), verifying better compatibility of weakly solvating electrolyte with anode. Whereas, NP electrolyte demonstrates inferior compatibility with HC anode, accompanied by distinct microcracks, a thick and nonuniform SEI layer on the electrode surface, which stems from continuous decomposition and accumulation of carbonate solvents. For NDPP electrolyte, moderate compatibility with HC anode can be obtained with a well-maintained surface morphology through constructing an even and dense SEI layer. These investigations substantiate effectiveness and feasibility of the integrated electrolyte engineering in collaborative interface regulation and admirable compatibility with anodes and high-voltage cathodes for durable SIBs.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTo further identify specific chemical compositions of EEIs, we conducted X-ray photoelectron spectroscopy (XPS) analysis of cycled NVPOF cathodes and HC anodes with different electrolytes, as revealed in \u003cstrong\u003eFig. 6b\u003c/strong\u003e and \u003cstrong\u003eSupplementary Fig. 19\u003c/strong\u003e. C 1s spectra reveal organic species (e. g., C-C, C-O and C=O), derived from the decomposition of free solvent molecules (PC, DEE). Additionally, F 1s spectra display two distinct peaks, corresponding to PO\u003cem\u003e\u003csub\u003ex\u003c/sub\u003e\u003c/em\u003eF\u003cem\u003e\u003csub\u003ey\u003c/sub\u003e\u003c/em\u003e and NaF, primarily derived from NaPF\u003csub\u003e6\u003c/sub\u003e salt. Comparative analysis manifests hybrid organic-inorganic coupling interfaces through the integrated\u0026nbsp;solvating electrolyte design. Besides, the presence of N-containing species in the CEI and SEI layers with NDPP electrolyte is detected from N 1s spectral analysis, demonstrating PFPN involves in interface modulation (\u003cstrong\u003eSupplementary Fig. 20\u003c/strong\u003e). Additionally, surface roughness and 3 D topography analysis of cycled electrodes with different electrolytes were characterized by atomic force microscopy (AFM), as shown in \u003cstrong\u003eFig. 6c\u003c/strong\u003e and \u003cstrong\u003eSupplementary Fig. 2\u003c/strong\u003e\u003cstrong\u003e1\u003c/strong\u003e. Specifically, the cycled NVPOF cathode in NDPP electrolyte exhibits a notably smoother morphology with a surface roughness of 57.4 nm, compared to those in ND and NP electrolytes (66.6 and 91.4 nm, respectively), consistent with above findings. Furthermore, time-of-flight secondary ion mass spectrometry (TOF-SIMS) was employed to explore component distribution in the CEI\u003csup\u003e50, 51\u003c/sup\u003e.\u003cstrong\u003e\u0026nbsp;Fig. 6d\u003c/strong\u003e and \u003cstrong\u003eFig. 6e\u003c/strong\u003e demonstrate 2 D and 3 D reconstruction images of CHO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e, NaF\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e and PO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e-\u003c/sup\u003e fragments on the cycled NVPOF cathode in NDPP, indicating the establishment of a thin, uniform and robust organic-inorganic coupling interface, in align with XPS results. Among them, organic components can promote mechanical strength and flexibility of the interface to effectively alleviate electrode deformation, while inorganic species exhibit high ionic conductivity and electronic insulation, conducive to enhancing interfacial stability\u003csup\u003e52, 53\u003c/sup\u003e. Additionally, oxidation and reduction properties of electrolytes were calculated to further deduce the interfacial compatibility (\u003cstrong\u003eFig. 6f\u003c/strong\u003e). According to the corresponding HOMO/LUMO energy levels, anti-oxidation stability of solvents is found to follow the sequence of PFPN \u0026gt; PC \u0026gt; DEE, while their anti-reduction stability is PFPN \u0026lt; PC \u0026lt; DEE. The integrated electrolyte demonstrates superior oxidative stability for high-voltage cathodes and compatibility with anodes due to introduction of PFPN. For Na\u003csup\u003e+\u003c/sup\u003e-solvent complexes, they exhibit declined HOMO/LUMO energy levels, revealing enhanced anti-oxidation stability and weakened anti-reduction stability. Nevertheless, Na\u003csup\u003e+\u003c/sup\u003e-solvent-PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e-\u003c/sup\u003e complexes have moderate redox stability with intermediate HOMO/LUMO energy levels. Overall, hybrid organic-inorganic coupling EEIs rich in F/N can be constructed on electrodes, leading to prominent interfacial and electrochemical stability. \u003cstrong\u003eFig. 7\u003c/strong\u003e schematically illustrates comprehensive assessments of conventional ND, NP and our designed NDPP electrolytes. Through multiscale experimental and theoretical investigations, NDPP has demonstrated remarkable merits in the following aspects: enhanced ionic conductivity, great compatibility with both electrodes due to synergistic oxidation and reduction stability, prominent electrochemical durability, and mitigated safety threat from non-flammability. Particularly, solvation and interfacial chemistry play a crucial role in electrochemical properties. For ND electrolyte with weakly solvated DEE, despite relatively better compatibility with anode, it inevitably exhibits a fragile CEI layer on cathode side accompanied by severe ether decomposition. For NP electrolyte with strongly solvated PC, there are poor organic-rich EEIs on both electrodes, resulting from unfavorable solvation and parasitic reactions from carbonate degradation. For the integrated electrolyte combined strongly solvated PC, weakly solvated DEE and non-solvated PFPN, robust EEIs rich in F/N can be constructed on electrodes, mainly attributed to the preferential decomposition of PFPN and unique solvation configuration with modulated ion-dipole and dipole-dipole interactions through molecular anchoring effect for abundant free solvents in the dilute electrolyte. More importantly, NDPP electrolyte endows SIBs with great potential in wide-temperature applications.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn conclusion, we have proposed a dipolar interaction-mediated molecular anchoring electrolyte integrated strongly solvated carbonate ester (PC), weakly solvated ether (DEE) and non-solvated PFPN for safe and durable SIBs. The electrolyte demonstrates a hierarchical solvation with abundant δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e\u0026minus;\u003c/sup\u003eF, δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e\u0026minus;\u003c/sup\u003eO and δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e\u0026minus;\u003c/sup\u003eN dipolar interactions among PF\u003csub\u003e6\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e anions and solvent molecules, especially PFPN, which activates non-coordinated PFPN and restricts free PC/DEE molecules. Multiscale experimental and theoretical investigations have manifested the integrated NDPP electrolyte enables to substantially alleviate solvent degradation at the electrodes, facilitate the construction of robust EEIs rich in F/N on both cathodes and anodes, ultimately promote comprehensive electrochemical improvements, compared with conventional ND and NP electrolytes. Particularly, the electrolyte features extraordinary electrochemical stability and reversibility. For NVPOF//Na half cells in NDPP, a significantly improved capacity retention up to 87.6% can be obtained even after 5000 cycles with enhanced CEs and EEs. Through matching with representative HC anode, the assembled NVPOF//HC full cells demonstrate prominent cycling stability. Furthermore, NDPP electrolyte is also well adaptable to commercial NVP and NT0102 cathodes, particularly, sustaining extremely stable operation of NVP cathode over a wide-temperature range from \u0026minus;\u0026thinsp;60 to 70 ℃. Strikingly, 95.2% of capacity retention can be observed after 900 cycles at 70 ℃, and reversible capacities of 70.2 and 51.2 mAh g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e can be maintained at -40 and \u0026minus;\u0026thinsp;60 ℃, respectively. This work involving a dipolar interaction-mediated molecular anchoring electrolyte design provides an encouraging avenue for the advancement of high-quality SIBs in extreme environments.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eMaterials\u003c/h2\u003e \u003cp\u003eNaPF\u003csub\u003e6\u003c/sub\u003e and DEE were purchased from DoDo Chem. PC and PFPN were purchased from Sigma-Aldrich Co., Ltd. and Shanghai Macklin Biochemical Technology Co., Ltd., respectively. The solvents were dried by the activated 4 \u0026Aring; molecular sieves for 72 h before use. Electrolytes were prepared in an argon-filled glovebox with O\u003csub\u003e2\u003c/sub\u003e and H\u003csub\u003e2\u003c/sub\u003eO content below 0.1 ppm. The NVPOF cathode material was prepared via a typical hydrothermal method according to our previous literature\u003csup\u003e\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e\u003c/sup\u003e. The NVP cathode materials were obtained from Youyan Technology Co., Ltd. The sodium layered oxide cathode (NT0102) were purchased from Canrd Technology Co., Ltd. The commercial HC material was purchased from Kuraray China Co., Ltd.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eMaterial characterizations\u003c/h2\u003e \u003cp\u003eIonic conductivities of the electrolytes were determined by a portable conductivity measuring meter (DDBJ-351L, Leici). Flammability tests of the electrolytes were carried out by igniting the electrolyte-soaked glass fiber separators in the fume hood. Raman spectrum measurements were carried out to reveal the structural details and solvation environments of the salts, solvents and electrolytes. NMR (Bruker AVANCE NEO, 500 MHz) technique was applied to further analyze the solvation characteristics and intermolecular interactions of the electrolytes. Specific morphological features of the cycled electrodes were obtained through SEM (HITACHI SU8010) and HRTEM (JEOL-2100 F, 200 kV) images. Furthermore, surface and interfacial compositions of the cycled electrodes can be characterized by XPS (VG Scientific with 300 W Al Kα source) measurements. All values of binding energy were referenced to the C 1s peak of carbon located at 284.8 eV. AFM (Bruker MultiMode 8) images were also employed to further investigate the surface morphology and roughness of the cycled electrodes. TOF-SIMS (TOF.SIMS5) of the cycled electrodes was conducted to reveal the chemical compositions and distributions in detail.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eElectrochemical measurements\u003c/h2\u003e \u003cp\u003eThe electrochemical properties of the prepared materials were characterized in the 2032-type coin cells. The NVPOF cathode containing the NVPOF material, carbon black and carboxymethyl cellulose sodium (CMC) at the weight ratio of 7:2:1 was prepared by spreading the aqueous slurry on carbon-coated Al foil as the current collector. Similarly, the NVP cathode was obtained by blending NVP power, Ketjen black and polyvinylidene fluoride (PVDF) with a weight ratio of 8:1:1 in N-methylpyrrolidone (NMP), the HC anode was prepared by mixing HC power, carbon black and PVDF at the weight ratio of 7:2:1 in NMP, and then the slurries were coated on carbon-coated Al foils. All working electrodes were dried at 100 ℃ under vacuum overnight. The active mass loading of these electrodes is in the range from 1.2 to 1.5 mg cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e. For the purchased NT0102 cathode, the active mass loading is about 8 mg cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e. The sodium-ion half cells are assembled in an Ar-filled glovebox. The counter electrode was the metallic Na foil. Glass filter (Whatman 934AH) was used as the separator for all batteries. GCD tests were conducted on the Neware battery test system. The sodium-ion half cells including NVPOF//Na, NT0102//Na, NVP//Na and HC//Na were investigated in a voltage range of 2-4.3, 2\u0026ndash;4, 2.5\u0026ndash;3.9 and 0.01-3 V (vs. Na/Na\u003csup\u003e+\u003c/sup\u003e), respectively. The electrochemical impedance spectroscopy (EIS) was carried out with a frequency ranging from 100 kHz to 0.01 Hz and a perturbation voltage amplitude of 5 mV. LSV tests of the electrolytes were performed in the stainless steel (SS)//Na half cells with a scanning rate of 0.5 mV s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. For full-cell fabrication, all HC anodes were pre-sodiated chemically, and the N/P ratio was controlled at about 1.2. The NVPOF//HC full cells were tested within a voltage window of 1.5 to 4.2 V.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eComputational details\u003c/h2\u003e \u003cp\u003eAccording to the molar ratio among the components, appropriate electrolyte boxes (15 NaPF\u003csub\u003e6\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;134 DEE, 15 NaPF\u003csub\u003e6\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;221 PC, 15 NaPF\u003csub\u003e6\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;56 DEE\u0026thinsp;+\u0026thinsp;92 PC\u0026thinsp;+\u0026thinsp;18 PFPN) were constructed. MD simulations of the electrolytes were carried out by using the Forcite package with COMPASS Ⅱ force field. Before conducting simulations with the NVT canonical ensemble for 50 ps lasted process, the density of each system was equilibrated with the NPT ensemble for tens of ps. The dynamic calculations were performed with a ultra-fine quality and a time step of 1 fs, and initiated with the current charges and random velocities. The DFT calculations for the salt, solvents and Na\u003csup\u003e+\u003c/sup\u003e-solvent complex molecules were conducted by using Dmol3 package with the GGA method in the form of the PBE. The atomic orbital-based double numerical plus polarization (DNP) basis set was used to describe the valence electrons. The binding energy of different Na\u003csup\u003e+\u003c/sup\u003e-solvent complex molecules were conducted by using Forcite package. The binding energy was defined as\u003csup\u003e\u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e\u003c/sup\u003e:\u003c/p\u003e \u003cp\u003e \u003cem\u003eE\u003c/em\u003e \u003csub\u003eb\u003c/sub\u003e = \u003cem\u003eE\u003c/em\u003e\u003csub\u003e[Na\u0026minus;solvent]\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e - \u003cem\u003eE\u003c/em\u003e\u003csub\u003eNa\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e - \u003cem\u003eE\u003c/em\u003e\u003csub\u003esolvent\u003c/sub\u003e\u003c/p\u003e \u003cp\u003ewhere \u003cem\u003eE\u003c/em\u003e\u003csub\u003e[Na\u0026minus;solvent]\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e is the energy of the Na\u003csup\u003e+\u003c/sup\u003e-solvent complex, \u003cem\u003eE\u003c/em\u003e\u003csub\u003esolvent\u003c/sub\u003e is the energy of the solvent molecule and \u003cem\u003eE\u003c/em\u003e\u003csub\u003eNa\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e is the energy of the sodium ion.\u003c/p\u003e \u003cp\u003eRestricted to construction and selection for suitable theoretical calculation electrolyte model considering calculated accuracy and complexity simultaneously, the existence of some special solvated structure could not be excluded, whereas the major coordination environment is relatively consistent and reasonable.\u003c/p\u003e \u003c/div\u003e "},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eCompeting interests\u003c/h2\u003e \u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e \u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that all the relevant data within this paper and its Supplementary Information file are available from the corresponding author upon request.\u003c/p\u003e\u003ch2\u003eAuthor contributions\u003c/h2\u003e \u003cp\u003eY.-L.H., Z.-Y.G. and X.-L.W. conceived the idea and designed the experiments. Y.-L.H. performed the material characterizations and electrochemical measurements with assistance from Z.-Y.G., H.-H.L., X.-T.W. and S.-Y.L. J.W. contributed to the NMR tests. Y.-L.H. analyzed the data and prepared the paper with contributions from all authors.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eWe acknowledge the financial supports from the National Key Research and Development Program of China (2023YFE0202000), National Natural Science Foundation of China (no. 52173246 and 52302222), Natural Science Foundation of Jilin Province (no. 20230101128JC and 20230508177RC), Science and Technology Planning Project of Guangzhou City (2023B03J1278), China Postdoctoral Science Foundation(2023T160094), and National Postdoctoral Program for Innovative Talents (No. BX20240062).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eUsiskin R\u003cem\u003e, et al.\u003c/em\u003e Fundamentals, status and promise of sodium-based batteries. \u003cem\u003eNat Rev Mater\u003c/em\u003e \u003cstrong\u003e6\u003c/strong\u003e, 1020-1035 (2021).\u003c/li\u003e\n\u003cli\u003eYao A, Benson SM, Chueh WC. Critically assessing sodium-ion technology roadmaps and scenarios for techno-economic competitiveness against lithium-ion batteries. \u003cem\u003eNat Energy\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 404-416 (2025).\u003c/li\u003e\n\u003cli\u003ePark S\u003cem\u003e, et al.\u003c/em\u003e Obtaining V\u003csub\u003e2\u003c/sub\u003e(PO\u003csub\u003e4\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e by sodium extraction from single-phase Na\u003csub\u003ex\u003c/sub\u003eV\u003csub\u003e2\u003c/sub\u003e(PO\u003csub\u003e4\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e (1\u0026thinsp;\u0026lt;\u0026thinsp;x\u0026thinsp;\u0026lt;\u0026thinsp;3) positive electrode materials. \u003cem\u003eNat Mater\u003c/em\u003e \u003cstrong\u003e24\u003c/strong\u003e, 234-242 (2024).\u003c/li\u003e\n\u003cli\u003eGuo Y-J\u003cem\u003e, et al.\u003c/em\u003e Sodium layered oxide cathodes: properties, practicality and prospects. \u003cem\u003eChem Soc Rev\u003c/em\u003e \u003cstrong\u003e53\u003c/strong\u003e, 7828-7874 (2024).\u003c/li\u003e\n\u003cli\u003eLu X, Li S, Li Y, Wu F, Wu C, Bai Y. From Lab to Application: Challenges and Opportunities in Achieving Fast Charging with Polyanionic Cathodes for Sodium‐Ion Batteries. \u003cem\u003eAdv Mater\u003c/em\u003e \u003cstrong\u003e36\u003c/strong\u003e, 2407359 (2024).\u003c/li\u003e\n\u003cli\u003eTang Y\u003cem\u003e, et al.\u003c/em\u003e Sustainable layered cathode with suppressed phase transition for long-life sodium-ion batteries. \u003cem\u003eNat Sustain\u003c/em\u003e \u003cstrong\u003e7\u003c/strong\u003e, 348-359 (2024).\u003c/li\u003e\n\u003cli\u003eZhou R\u003cem\u003e, et al.\u003c/em\u003e Constructing Anion Solvation Microenvironment Toward Durable High‐Voltage Sodium‐Based Batteries. \u003cem\u003eAdv Mater\u003c/em\u003e \u003cstrong\u003e37\u003c/strong\u003e, 2416748 (2025).\u003c/li\u003e\n\u003cli\u003eXie K, Ji Y, Yang L, Pan F. Electrolyte Design Strategies to Construct Stable Cathode‐Electrolyte Interphases for High‐Voltage Sodium‐Ion Batteries. \u003cem\u003eAdv Energy Mater\u003c/em\u003e \u003cstrong\u003e15\u003c/strong\u003e, 2405301 (2025).\u003c/li\u003e\n\u003cli\u003eZhang F\u003cem\u003e, et al.\u003c/em\u003e Emerging Chemistry for Wide-Temperature Sodium-Ion Batteries. \u003cem\u003eChem Rev\u003c/em\u003e \u003cstrong\u003e124\u003c/strong\u003e, 4778-4821 (2024).\u003c/li\u003e\n\u003cli\u003eJiang L\u003cem\u003e, et al.\u003c/em\u003e Rational design of anti-freezing electrolytes for extremely low-temperature aqueous batteries. \u003cem\u003eNat Energy\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e, 839-848 (2024).\u003c/li\u003e\n\u003cli\u003eKo S\u003cem\u003e, et al.\u003c/em\u003e Rapid safety screening realized by accelerating rate calorimetry with lab-scale small batteries. \u003cem\u003eNat Energy\u003c/em\u003e, (2025). https://doi.org/10.1038/s41560-025-01751-7.\u003c/li\u003e\n\u003cli\u003eZhang J, Gai J, Song K, Chen W. Advances in electrode/electrolyte interphase for sodium-ion batteries from half cells to full cells. \u003cem\u003eCell Rep Phys Sci\u003c/em\u003e \u003cstrong\u003e3\u003c/strong\u003e, 100868 (2022).\u003c/li\u003e\n\u003cli\u003eZhang J\u003cem\u003e, et al.\u003c/em\u003e Critical review on cathode electrolyte interphase towards stabilization for sodium-ion batteries. \u003cem\u003eNano Energy\u003c/em\u003e \u003cstrong\u003e128\u003c/strong\u003e, 109814 (2024).\u003c/li\u003e\n\u003cli\u003eZheng X\u003cem\u003e, et al.\u003c/em\u003e Critical effects of electrolyte recipes for Li and Na metal batteries. \u003cem\u003eChem\u003c/em\u003e \u003cstrong\u003e7\u003c/strong\u003e, 2312-2346 (2021).\u003c/li\u003e\n\u003cli\u003eVinay B\u003cem\u003e, et al.\u003c/em\u003e Fluorine-free electrolytes in batteries: principles, strategies, and advances. \u003cem\u003eEnergy Environ Sci\u003c/em\u003e, (2025). https://doi.org/10.1039/D4EE04820B.\u003c/li\u003e\n\u003cli\u003eMeng YS, Srinivasan V, Xu K. Designing better electrolytes. \u003cem\u003eScience\u003c/em\u003e \u003cstrong\u003e378\u003c/strong\u003e, 1065 (2022).\u003c/li\u003e\n\u003cli\u003eLi Y\u003cem\u003e, et al.\u003c/em\u003e Ether-based electrolytes for sodium ion batteries. \u003cem\u003eChem Soc Rev\u003c/em\u003e \u003cstrong\u003e51\u003c/strong\u003e, 4484-4536 (2022).\u003c/li\u003e\n\u003cli\u003eLi C\u003cem\u003e, et al.\u003c/em\u003e Nonaqueous Liquid Electrolytes for Sodium‐Ion Batteries: Fundamentals, Progress and Perspectives. \u003cem\u003eAdv Energy Mater\u003c/em\u003e \u003cstrong\u003e13\u003c/strong\u003e, 2301758 (2023).\u003c/li\u003e\n\u003cli\u003eChen J, Zhang H, Fang M, Ke C, Liu S, Wang J. Design of Localized High-Concentration Electrolytes via Donor Number. \u003cem\u003eACS Energy Lett\u003c/em\u003e \u003cstrong\u003e8\u003c/strong\u003e, 1723-1734 (2023).\u003c/li\u003e\n\u003cli\u003eRen X\u003cem\u003e, et al.\u003c/em\u003e Localized High-Concentration Sulfone Electrolytes for High-Efficiency Lithium-Metal Batteries. \u003cem\u003eChem\u003c/em\u003e \u003cstrong\u003e4\u003c/strong\u003e, 1877-1892 (2018).\u003c/li\u003e\n\u003cli\u003eZeng Z\u003cem\u003e, et al.\u003c/em\u003e Non-flammable electrolytes with high salt-to-solvent ratios for Li-ion and Li-metal batteries. \u003cem\u003eNat Energy\u003c/em\u003e \u003cstrong\u003e3\u003c/strong\u003e, 674-681 (2018).\u003c/li\u003e\n\u003cli\u003eFang H\u003cem\u003e, et al.\u003c/em\u003e Regulating Ion‐Dipole Interactions in Weakly Solvating Electrolyte towards Ultra‐Low Temperature Sodium‐Ion Batteries. \u003cem\u003eAngew Chem Int Ed\u003c/em\u003e \u003cstrong\u003e63\u003c/strong\u003e, e202400539 (2024).\u003c/li\u003e\n\u003cli\u003eNiu M\u003cem\u003e, et al.\u003c/em\u003e Approaching fast ion transport via anion\u0026ndash;dipole interaction in weakly solvated electrolytes enables stable Li-plating chemistry. \u003cem\u003eNatl Sci Rev\u003c/em\u003e \u003cstrong\u003e12\u003c/strong\u003e, nwaf065 (2025).\u003c/li\u003e\n\u003cli\u003eWang C\u003cem\u003e, et al.\u003c/em\u003e A weakly coordinating-intervention strategy for modulating Na\u003csup\u003e+\u003c/sup\u003e solvation sheathes and constructing robust interphase in sodium-metal batteries. \u003cem\u003eNat Commun\u003c/em\u003e \u003cstrong\u003e15\u003c/strong\u003e, 6292 (2024).\u003c/li\u003e\n\u003cli\u003eJin Y\u003cem\u003e, et al.\u003c/em\u003e Low-solvation electrolytes for high-voltage sodium-ion batteries. \u003cem\u003eNat Energy\u003c/em\u003e \u003cstrong\u003e7\u003c/strong\u003e, 718-725 (2022).\u003c/li\u003e\n\u003cli\u003eWang Y\u003cem\u003e, et al.\u003c/em\u003e Fluorine Chemistry in Rechargeable Batteries: Challenges, Progress, and Perspectives. \u003cem\u003eChem Rev\u003c/em\u003e \u003cstrong\u003e124\u003c/strong\u003e, 3494-3589 (2024).\u003c/li\u003e\n\u003cli\u003eChen W\u003cem\u003e, et al.\u003c/em\u003e Hybrid solvating electrolytes for practical sodium-metal batteries. \u003cem\u003eJoule\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e, 101811 (2025).\u003c/li\u003e\n\u003cli\u003eWang M, Zheng M, Lu J, You Y. High-entropy electrolyte toward battery working under extreme conditions. \u003cem\u003eJoule\u003c/em\u003e \u003cstrong\u003e8\u003c/strong\u003e, 2467-2482 (2024).\u003c/li\u003e\n\u003cli\u003eKim SC\u003cem\u003e, et al.\u003c/em\u003e High-entropy electrolytes for practical lithium metal batteries. \u003cem\u003eNat Energy\u003c/em\u003e \u003cstrong\u003e8\u003c/strong\u003e, 814-826 (2023).\u003c/li\u003e\n\u003cli\u003eZeng Y\u003cem\u003e, et al.\u003c/em\u003e High-entropy mechanism to boost ionic conductivity. \u003cem\u003eScience\u003c/em\u003e \u003cstrong\u003e378\u003c/strong\u003e, 1320-1324 (2022).\u003c/li\u003e\n\u003cli\u003eYang Z\u003cem\u003e, et al.\u003c/em\u003e Modulating ion\u0026ndash;dipole interactions in nonflammable phosphonate-based electrolyte for safe and stable sodium-ion pouch cells. \u003cem\u003eNatl Sci Rev\u003c/em\u003e \u003cstrong\u003e12\u003c/strong\u003e, nwae466 (2025).\u003c/li\u003e\n\u003cli\u003eXu Z, Zhang X, Yang J, Cui X, Nuli Y, Wang J. High-voltage and intrinsically safe electrolytes for Li metal batteries. \u003cem\u003eNat Commun\u003c/em\u003e \u003cstrong\u003e15\u003c/strong\u003e, 9856 (2024).\u003c/li\u003e\n\u003cli\u003eLiao Y\u003cem\u003e, et al.\u003c/em\u003e Pentafluoro(phenoxy)cyclotriphosphazene Stabilizes Electrode/Electrolyte Interfaces for Sodium‐Ion Pouch Cells of 145 Wh Kg\u003csup\u003e\u0026minus;1\u003c/sup\u003e. \u003cem\u003eAdv Mater\u003c/em\u003e \u003cstrong\u003e36\u003c/strong\u003e, 2312287 (2024).\u003c/li\u003e\n\u003cli\u003eZhang H\u003cem\u003e, et al.\u003c/em\u003e High-safety and high-voltage lithium metal batteries enabled by nonflammable diluted highly concentrated electrolyte. \u003cem\u003eNano Res\u003c/em\u003e \u003cstrong\u003e17\u003c/strong\u003e, 2638-2645 (2023).\u003c/li\u003e\n\u003cli\u003eChen J\u003cem\u003e, et al.\u003c/em\u003e Nonflammable Succinonitrile‐Based Deep Eutectic Electrolyte for Intrinsically Safe High‐Voltage Sodium‐Ion Batteries. \u003cem\u003eAdv Mater\u003c/em\u003e \u003cstrong\u003e36\u003c/strong\u003e, 2400169 (2024).\u003c/li\u003e\n\u003cli\u003eKelchtermans A-S\u003cem\u003e, et al.\u003c/em\u003e Superconcentration Strategy Allows Sodium Metal Compatibility in Deep Eutectic Solvents for Sodium-Ion Batteries. \u003cem\u003eACS Omega\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e, 42343-42352 (2024).\u003c/li\u003e\n\u003cli\u003eHuang Y, Zhao L, Li L, Xie M, Wu F, Chen R. Electrolytes and Electrolyte/Electrode Interfaces in Sodium‐Ion Batteries: From Scientific Research to Practical Application. \u003cem\u003eAdv Mater\u003c/em\u003e \u003cstrong\u003e31\u003c/strong\u003e, 1808393 (2019).\u003c/li\u003e\n\u003cli\u003eQin M\u003cem\u003e, et al.\u003c/em\u003e Rejuvenating Propylene Carbonate‐based Electrolyte Through Nonsolvating Interactions for Wide‐Temperature Li‐ions Batteries. \u003cem\u003eAdv Energy Mater\u003c/em\u003e \u003cstrong\u003e12\u003c/strong\u003e, 2201801 (2022).\u003c/li\u003e\n\u003cli\u003eLi E\u003cem\u003e, et al.\u003c/em\u003e Hierarchical doping electrolyte solvation engineering to achieve high-performance sodium-ion batteries in wide temperature. \u003cem\u003eEnergy Storage Mater\u003c/em\u003e \u003cstrong\u003e73\u003c/strong\u003e, 103805 (2024).\u003c/li\u003e\n\u003cli\u003eChen Y\u003cem\u003e, et al.\u003c/em\u003e Trace ethylene carbonate-mediated low-concentration ether-based electrolytes for high-voltage lithium metal batteries. \u003cem\u003eEnergy Environ Sci\u003c/em\u003e \u003cstrong\u003e17\u003c/strong\u003e, 5613-5626 (2024).\u003c/li\u003e\n\u003cli\u003eCui X\u003cem\u003e, et al.\u003c/em\u003e 4.2 V O3‐Layered Cathodes in Sodium‐Ion Pouch Cells Enabled by an Intermolecular‐Reinforced Ether Electrolyte. \u003cem\u003eAdv Mater\u003c/em\u003e \u003cstrong\u003e37\u003c/strong\u003e, 2415611 (2025).\u003c/li\u003e\n\u003cli\u003eWang X\u003cem\u003e, et al.\u003c/em\u003e Anion-mediated approach to overcome oxidation in ether electrolytes for high-voltage sodium-ion batteries. \u003cem\u003eNat Commun\u003c/em\u003e \u003cstrong\u003e16\u003c/strong\u003e, 2536 (2025).\u003c/li\u003e\n\u003cli\u003eWu Y\u003cem\u003e, et al.\u003c/em\u003e Electrostatic Potential as Solvent Descriptor to Enable Rational Electrolyte Design for Lithium Batteries. \u003cem\u003eAdv Energy Mater\u003c/em\u003e \u003cstrong\u003e13\u003c/strong\u003e, 2300259 (2023).\u003c/li\u003e\n\u003cli\u003eYu Z\u003cem\u003e, et al.\u003c/em\u003e Molecular design for electrolyte solvents enabling energy-dense and long-cycling lithium metal batteries. \u003cem\u003eNat Energy\u003c/em\u003e \u003cstrong\u003e5\u003c/strong\u003e, 526-533 (2020).\u003c/li\u003e\n\u003cli\u003eLi N\u003cem\u003e, et al.\u003c/em\u003e Insight into the probability of ethoxy(pentafluoro)cyclotriphosphazene (PFPN) as the functional electrolyte additive in lithium\u0026ndash;sulfur batteries. \u003cem\u003eRSC Adv\u003c/em\u003e \u003cstrong\u003e14\u003c/strong\u003e, 12754-12761 (2024).\u003c/li\u003e\n\u003cli\u003eYu J\u003cem\u003e, et al.\u003c/em\u003e Regulated Li\u003csup\u003e+\u003c/sup\u003e Solvation via Competitive Coordination Mechanism of Organic Cations for High Voltage and Fast Charging Lithium Metal Batteries. \u003cem\u003eAngew Chem Int Ed\u003c/em\u003e \u003cstrong\u003e64\u003c/strong\u003e, e202416092 (2024).\u003c/li\u003e\n\u003cli\u003eWang M\u003cem\u003e, et al.\u003c/em\u003e Temperature-responsive solvation enabled by dipole-dipole interactions towards wide-temperature sodium-ion batteries. \u003cem\u003eNat Commun\u003c/em\u003e \u003cstrong\u003e15\u003c/strong\u003e, 8866 (2024).\u003c/li\u003e\n\u003cli\u003eZhao Z, Liu C, Lai T, Cui Z, Manthiram A. Macromolecule‐Enriched Solvation Enabling High‐Voltage Sodium‐Ion Batteries. \u003cem\u003eAngew Chem Int Ed\u003c/em\u003e, e202423625 (2025).\u003c/li\u003e\n\u003cli\u003eLai P\u003cem\u003e, et al.\u003c/em\u003e Revealing the evolution of solvation structure in low-temperature electrolytes for lithium batteries. \u003cem\u003eEnergy Storage Mater\u003c/em\u003e \u003cstrong\u003e67\u003c/strong\u003e, 103314 (2024).\u003c/li\u003e\n\u003cli\u003eFeng YH\u003cem\u003e, et al.\u003c/em\u003e Dual‐Anionic Coordination Manipulation Induces Phosphorus and Boron‐Rich Gradient Interphase Towards Stable and Safe Sodium Metal Batteries. \u003cem\u003eAngew Chem Int Ed\u003c/em\u003e \u003cstrong\u003e64\u003c/strong\u003e, e202415644 (2024).\u003c/li\u003e\n\u003cli\u003eLi Y\u003cem\u003e, et al.\u003c/em\u003e Sole‐Solvent High‐Entropy Electrolyte Realizes Wide‐Temperature and High‐Voltage Practical Anode‐Free Sodium Pouch Cells. \u003cem\u003eAdv Mater\u003c/em\u003e \u003cstrong\u003e37\u003c/strong\u003e, 2419764 (2025).\u003c/li\u003e\n\u003cli\u003eGao Y, Yao Y, Shi P, Huang F, Jiang Y, Yu Y. Advanced Interphases Layers for Dendrite-Free Sodium Metal Anodes. \u003cem\u003eACS Appl Mater Interfaces\u003c/em\u003e \u003cstrong\u003e17\u003c/strong\u003e, 17881-17894 (2025).\u003c/li\u003e\n\u003cli\u003eLiu P\u003cem\u003e, et al.\u003c/em\u003e Inorganic\u0026ndash;Organic Hybrid Multifunctional Solid Electrolyte Interphase Layers for Dendrite‐Free Sodium Metal Anodes. \u003cem\u003eAngew Chem Int Ed\u003c/em\u003e \u003cstrong\u003e62\u003c/strong\u003e, e202312413 (2023).\u003c/li\u003e\n\u003cli\u003eGu Z-Y\u003cem\u003e, et al.\u003c/em\u003e Precisely controlled preparation of an advanced Na\u003csub\u003e3\u003c/sub\u003eV\u003csub\u003e2\u003c/sub\u003e(PO\u003csub\u003e4\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003eF cathode material for sodium ion batteries: the optimization of electrochemical properties and electrode kinetics. \u003cem\u003eInorg Chem Front\u003c/em\u003e \u003cstrong\u003e6\u003c/strong\u003e, 988-995 (2019).\u003c/li\u003e\n\u003cli\u003eLiang H-J\u003cem\u003e, et al.\u003c/em\u003e Electrolyte Chemistry toward Ultrawide-Temperature (\u0026minus;25 to 75 \u0026deg;C) Sodium-Ion Batteries Achieved by Phosphorus/Silicon-Synergistic Interphase Manipulation. \u003cem\u003eJ Am Chem Soc\u003c/em\u003e\u003cstrong\u003e146\u003c/strong\u003e, 7295-7304 (2024).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"nature-portfolio","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Nature Portfolio","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"ejp","reportingPortfolio":"","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"sodium-ion battery, molecular anchoring electrolyte, dipolar interaction, interfacial modulation, non-flammability","lastPublishedDoi":"10.21203/rs.3.rs-6768086/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6768086/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eGiven intractable challenges faced by practical sodium-ion batteries (SIBs) in safety, ultralong lifespan and broad temperature adaptability with synergistic interfacial compatibility, persistent efforts in electrolyte engineering are imperative to expedite their commercialization. Here we design a molecular anchoring electrolyte with remarkable flame retardancy, oxidative/reductive reliability and electrochemical durability against both electrodes. Through multiple dipolar interactions (δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e-\u003c/sup\u003eF, δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e-\u003c/sup\u003eO and δ\u003csup\u003e+\u003c/sup\u003eH-δ\u003csup\u003e-\u003c/sup\u003eN), a dynamic hierarchical solvation network is constructed and its unique interface stabilization mechanism is revealed by multiscale characterizations and theoretical insights. The electrolyte endows high-voltage phosphate cathode with extraordinary electrochemical durability (87.6% of capacity retention after 5000 cycles) through constructing robust interphases enriched with F and N. Great compatibility with commercial layered oxide further indicates its versatility. Strikingly, the electrolyte also sustains stable operation under extreme temperatures (-60 ~ 70 °C). Our proposed dipolar interaction regulation mechanism provides a new paradigm for designing safe and durable electrolytes, stimulating practical application of wide-temperature SIBs in extreme environment energy storage.\u003c/p\u003e","manuscriptTitle":"Dipolar interaction-mediated molecular anchoring electrolyte enables wide-temperature sodium-ion batteries with enhanced safety and durability","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-06 09:30:50","doi":"10.21203/rs.3.rs-6768086/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"3c0fce01-4240-43e0-b22e-6b80eb8d0e32","owner":[],"postedDate":"June 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":49597910,"name":"Physical sciences/Chemistry/Energy"},{"id":49597911,"name":"Physical sciences/Energy science and technology/Energy storage/Batteries"}],"tags":[],"updatedAt":"2026-03-25T20:15:43+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-06 09:30:50","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6768086","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6768086","identity":"rs-6768086","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}