Fast-kinetics and high-compatibility aqueous cadmium-metal battery for next-generation energy storage infrastructures

Fast-kinetics and high-compatibility aqueous cadmium-metal battery for next-generation energy storage infrastructures | 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 Physical Sciences - Article Fast-kinetics and high-compatibility aqueous cadmium-metal battery for next-generation energy storage infrastructures Hui Ying Yang, Yang-Feng Cui, Haobin Song, Jingjing Yao, Qi Hao, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4646240/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 01 Jul, 2025 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Abstract Aqueous metal batteries have the potential to revolutionize the next-generation energy storage infrastructures due to their high energy density, high safety and low cost. However, two major issues of dendrite growth and corrosion reactions in metal anodes have hindered the deployment of this technology. To address these issues, we report an ideal candidate: aqueous cadmium-metal battery (ACB). The metal cadmium (Cd) anode not only shows a high specific capacity (476.5 mAh g -1 ) but also offers suitable redox potential (-0.4 V versus standard hydrogen electrode). Additionally, we introduce this ACB operating with a low-cost chloride electrolyte composed of CdCl 2 and NH 4 Cl in water. The inclusion of NH 4 Cl reconstructs the hydrogen bond network of aqueous electrolyte and forms tetrachlorocomplex ([CdCl 4 ] 2- ), which facilitate ultrafast reaction kinetics in ACBs and endow dendrite-free/corrosion-resistant capabilities in Cd anodes. Consequently, the tailored electrolyte achieves a convincing Coulombic efficiency (99.93%) for Cd plating/stripping behavior at a high anode utilization of 55.5%, making it suitable for practical applications. More importantly, the ACBs demonstrate outstanding compatibility paired with coordination-type, intercalation-type and capacitance-type cathodes, exhibiting excellent high-/low-rate and long-term rechargeable capabilities. On a practical note, the high-load ACB with a low negative-to-positive capacity ratio of 1.91 delivers an impressive lifespan of 800 cycles. In summary, our work suggests a practical aqueous battery capable of supporting robust energy storage infrastructures. Physical sciences/Chemistry/Electrochemistry/Batteries Physical sciences/Energy science and technology/Energy storage Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction The transition from carbon-rich fossil fuels to environmentally friendly renewable energy sources to achieve decarbonization has become a fundamental goal across academia, industry, and government. 1 However, the increasing reliance on renewable but intermittent energy sources—such as solar, wind, and tidal power—necessitates the development of cost-effective, safe, and durable energy storage solutions capable of storing large amounts of electrical energy. 2 While lithium-ion batteries have successfully dominated the market for applications requiring high energy density, they may not be the optimal choice for all scenarios, particularly for grid-scale energy storage, due to the use of flammable organic electrolytes and scarce electrode materials. 3 In contrast, aqueous metal batteries have emerged as promising candidates in various energy storage contexts, offering high power density, fast-charging capability, minimized safety risks, and lower manufacturing costs. 4 However, the current problem lies in the absence of convincing aqueous energy storage systems capable of supporting the decarbonization of renewable electricity generation. This explains why century-old lead-acid batteries with a low energy density (30-50 Wh kg - 1 ) remain indispensable in grid-scale energy storage, portable electronics, and electric vehicles. 5,6 In recent years, rechargeable aqueous zinc-metal batteries (AZBs) have been considered promising candidates for multi-scenario storage applications. 7,8 The metallic zinc (Zn) is one of the few metal anodes capable of reversible plating/stripping behavior in aqueous medias while offering a suitable redox potential (-0.76 V vs. standard hydrogen electrode, SHE) and high specific capacity (820 mAh g - 1 ), as shown in Fig. 1a. AZBs fitted with manganese (Mn)-based, vanadium (V)-based, and organic cathodes are attractive for their high theoretical specific energy (60-250 Wh kg - 1 ). 9 However, the fatal issues of cell shorting by dendrites and passivation due to corrosion have hindered the deployment of this technology. 10,11 Motivated by this background, several emerging metal anodes are being explored to replace Zn anodes, such as iron (Fe), indium (In), nickel (Ni), tin (Sn), copper (Cu), and bismuth (Bi). While these metal anodes exhibit impressive electrochemical properties, they face intrinsic limitations for next-generation energy storage applications (Fig. 1a). For instance, Fe anodes suffer from passivation reactions that block ionic shuttling. 12 In is a rare and noble metal, making it unsuitable for large-scale energy storage. 13 The plating/stripping behavior of Ni anode experiences sluggish kinetics, resulting in high potential polarization. 14,15 The redox potentials of the Cu 2+ /Cu (+0.34 V vs. SHE) and Bi 3+ /Bi (+0.32 V vs. SHE) couples are too high for practical use in batteries. 16,17 In contrast, acidic Sn-metal batteries paired with acidic cathodes seem to be a more promising candidate. However, the use of an ion exchange membrane to separate the anode electrolyte and cathode electrolyte, thereby preventing Sn 2+ shuttle and the subsequent redox reactions of Sn 3+ /Sn 2+ at the cathode surface, is a prerequisite for the proper functioning of this battery. 18 It results in that the energy density of acidic Sn-metal battery actually depends on the concentration of H + and solubility of discharge products in electrolytes and the use of ion exchange membranes increases the manufacturing costs. To overcome these issues, we report an ideal alternative to existing aqueous metal batteries: the aqueous cadmium-metal battery (ACB). Herein, the metallic cadmium (Cd) anode not only possesses the dendrite-free and corrosion-resistant capabilities but also exhibits a high specific capacity (476.5 mAh g - 1 ) and a suitable redox potential (-0.4 V vs. SHE), as shown in Fig 1a. Consequently, this gives Cd anode comprehensive advantages over other metal anodes, especially the Zn anode (Fig. 1a, b). Additionally, we disclose this ACB operating with a low-cost chloride electrolyte composed of 1 M CdCl 2 + 6 M NH 4 Cl in water. The introduction of NH 4 Cl reconstructs the hydrogen bond network among H 2 O molecules and forms tetrachlorocomplex, [CdCl 4 ] 2 - species. This restructuring facilitates the ultrafast charge-transfer, desolvation and reaction kinetics in ACB, while concurrently suppressing the corrosion reaction and contributing to smooth Cd plating/stripping behaviors. Consequently, the tailored electrolyte enables convincing Coulombic efficiency (CE) of 99.93% and the highest aging CE of 99.34% for Cd plating/stripping behaviors at a high anode utilization (AU) of 55.5% (5 mAh cm - 2 ). This practical performance makes numerous high-energy and durable aqueous batteries based on Cd anodes feasible, including but not limited to Cd//MnO 2 cells, Cd//V 2 O 5 cells, Cd//organic cells, Cd-air cells, and hybrid Cd-ion capacitors (Fig. 1c, d). Their diversity and universality are confirmed by using three types of representative cathodes, intercalation-type V 2 O 5 , capacitance-type active carbon (AC) and coordination-type organic polyaniline (PANI). Specially, the high-load Cd//PANI full cell delivers a stable cycling performance over 800 cycles, with a negative-to-positive capacity (N/P) ratio of 1.91 and a cumulative areal capacity of 2.57 Ah cm - 2 . Overall, our work suggests a practical ACB capable of supporting robust energy storage infrastructures. Results Fundamentals of aqueous chloride electrolytes It is known that NH 4 + in aqueous solution shares many similar properties with H 2 O, 19,20 and can form hydrogen bonds with four H 2 O molecules. 21 On the other hand, in dilute electrolytes, cations tend to be solvated by polar H 2 O molecules to form the hydrated cations. 22 Based on these fundamental properties, our strategy involves introducing NH 4 Cl as a supporting salt in a dilute CdCl₂ solution to reconstruct the hydrogen bond network among H 2 O molecules and modify the aqua ligands of Cd 2+ through the extra Lewis base of Cl - from NH 4 Cl, aiming to reduce water activity without compromising the original advantages of the dilute electrolyte. Starting with the baseline electrolyte of 1 M CdCl 2 (referred to as 1M), we first examined the electrolyte structure of adding different concentrations of NH 4 Cl (1 M CdCl 2 + 1 M NH 4 Cl, 1 M CdCl 2 + 2 M NH 4 Cl, 1 M CdCl 2 + 4 M NH 4 Cl, 1 M CdCl 2 + 6 M NH 4 Cl, and 1 M CdCl 2 + 7.5 M NH 4 Cl electrolytes referred to as 1M1M, 1M2M, 1M4M, 1M6M, and 1M7.5M, respectively). In Fig. 2a, Fourier transform infrared spectroscopy (FTIR) at the 1100 cm - 1 band of NH 3 was absent in the spectra of all NH 4 + -containing electrolytes. This indicated that the hydrolysis behavior of NH 4 + to produce NH 3 ·H 2 O and H + can be considered negligible. 23 In contrast, the peak of NH 4 + appeared at 1440 cm - 1 band and became increasingly prominent with higher concentrations of NH 4 Cl. They existed in aqueous solution as hydrated NH 4 + , which is confirmed by the presence of hydrogen bond between NH 4 + and H 2 O, indicated by the bands at 3360, 3200, and 3050 cm - 1 in the spectra. 23,24 The impact of NH 4 + on the hydrogen bond network of H 2 O molecules were analyzed through Raman spectra (Fig. 2b), wherein the O-H stretching for H 2 O molecules in the high-frequency range were deconvoluted into three peaks corresponding to the strongly, weakly, and slightly hydrogen-bonded components at the peaks of 3248.9, 3468.4, and 3628.8 cm - 1 (Supplementary Fig. 1). From pure water to 1M7.5M electrolyte, the hydrogen networks of H 2 O molecules gradually transitioned from the strong hydrogen bond-dominated conformation to the weak hydrogen bond-dominated conformation; meanwhile, the peak intensity corresponding to NH 4 + at the peaks of 2878.7, 3032.1, and 3115.0 cm - 1 gradually increased (Fig. 2b and Supplementary Fig. 1). They demonstrated that the introduction of NH 4 + into the 1M electrolyte disrupted the original hydrogen bond environment among H 2 O molecules and subsequently participated in forming a new hydrogen bond network between NH 4 + and H 2 O as hydrate NH 4 + . Furthermore, as the concentration of NH 4 Cl increased, the shifts of 1 H nuclear magnetic resonance ( 1 H NMR) and 17 O NMR signals of H 2 O also indicated the enhanced hydrogen bond interactions between H 2 O and NH 4 + as hydrated NH 4 + but decreased hydrogen bond interactions among H 2 O molecules (Supplementary Fig. 2). Besides the NH 4 + -involved hydrogen bond network, we observed that the formation of tetrachlorocomplex, [CdCl 4 ] 2− , was confirmed at the peak of about 260 cm −1 with the increased NH 4 Cl concentration, as shown in the low-frequency Raman spectra of Fig. 2c. 25,26 This confirmed our design concept (Fig. 2d), where NH 4 Cl provided extra Lewis base of Cl − that complexed with Lewis acid of Cd 2+ to transform the hydrated Cd 2+ to [CdCl 4 ] 2− . Note that this transformation addressed a series of side reactions initiated by hydrated cations, such as hydrogen evolution reaction (HER) and dendritic growth, as discussed later. Therefore, the NH 4 Cl imparted versatility to dilute 1M electrolyte, involving rich NH 4 + -involved H-bond network and [CdCl 4 ] 2− . Electrochemistry of Cd anodes In our study aimed at developing practical energy storage infrastructures, we thus employed rigorous testing conditions to screen the tailored aqueous electrolytes. This involved evaluating the CE of Cd plating/stripping behaviors at a substantial AU of 33% (3 mAh cm − 2 ), using a precise two-electrode Swagelok-type cell (Supplementary Figs. 3−5). Fig. 2e summarized the performance in different electrolyte. The average CE of Cd plating/stripping behaviors in 1M6M electrolyte was the highest and reached 99.89% (400 cycles), much higher than the average CE of 1M (99.76%) obtained from the reversible 129 cycles. It demonstrated the introduction of 6 M NH 4 Cl significantly improved the performance of the Cd anode. Consequently, the 1M6M electrolyte was identified as the optimal choice for subsequent research. We further utilized Cd//Cu cells to assess the performance of the ACB at a higher AU of 55% (5 mAh cm −2 ) and a higher current density of 10 mA cm −2 , aiming to meet the demanding requirements of practical applications. 27 The performance was compared against that of the baseline 1M electrolyte in the ACB and commonly used 2 M ZnSO 4 (2ZS) electrolyte in the AZB, 7 as depicted in Fig. 2f and Supplementary Fig. 6. An initial CE of 99.50% and an average CE of 99.93% over 300 cycles were achieved in 1M6M electrolyte, which reflect the highest Cd plating/stripping efficiency at a practical condition. By contrast, an initial CE of 98.89% and average CE of 99.86% within reversible 39 cycles were obtained in baseline 1M electrolyte, which are still obviously superior to the Zn plating/stripping efficiency of initial CE (94.20%) and average CE (98.51% within reversible 33 cycles). Furthermore, to figure out the highest reversibility of Cd anode in 1M6M electrolyte, we analyzed the anode morphologies after cycling by a scanning electron microscopy (SEM). It was observed that Cd anode in 1M6M electrolyte demonstrated dendrite-free capability with a smooth and dense morphology (Fig. 2g), thereby affording the excellently electrochemical performance. In contrast, the Cd anode in 1M electrolyte showed randomly oriented plate-like deposits (Supplementary Fig. 7a), whereas the moss-like dendrites that more easily leads to cell shorting formed on the Zn anode (Supplementary Fig. 7b). Considering that energy storage infrastructures necessarily involve intermittent usage in practical applications, we further evaluated the aging CE of restoring aging-induced anode in aqueous electrolyte under an extremely stringent condition, as shown in Fig. 2h. We observed that long-term storage of metal Cd in aqueous electrolytes did not lead to capacity loss caused by corrosion. This was evidenced by stable voltage polarization curves of plating, aging and stripping processes (Fig. 2i), high average CE of ~99.34 (Fig. 2j), and highly overlapping plating/stripping curves over cycles (Fig. 2k). To our knowledge, no current metal battery system demonstrated this capability, even under conditions of minimal anode utilization. For example, the promising Zn anode only achieved an aging CE of less 75% (Fig. 2j) and suffered from obvious voltage polarization-induced cell failure in second cycle due to capacity loss caused by corrosion of aqueous electrolyte (Supplementary Fig. 8a, b). 11 By the way, although Cd anode was cycled only 6 cycles in 1M electrolyte, its failure was not due to corrosion reaction but rather to cell shorting (Supplementary Fig. 8c, d). Additionally, it exhibited a high average aging CE of 97.58% (Fig. 2j). This further indicated that Cd anode is inherently corrosion-resistant in aqueous electrolytes. Dendrite-free Cd plating/stripping behaviors To further validate the dendrite-free capability of ACB and exclude homogeneous effect during plating process, we investigated Cd plating/stripping behaviors on Cu foil substrate at a high areal capacity of 5 mAh cm −2 . The morphological evolutions were observed by ex-situ SEM (Supplementary Figs. 9−11). The Cd deposits in 1M electrolyte could maintain regular texture morphology up to 3 mAh cm −2 , whereas, beyond this capacity, uncontrolled dendrites began to form and grow (Supplementary Fig. 9). In contrast, the plating process for Cd in 1M6M electrolyte consistently showed a regular grain growth process (Supplementary Fig. 10). However, the Zn plating process was accompanied by the pronounced moss-like dendrite growth (Supplementary Fig. 11). We subsequently studied the cross-section morphologies of Cd deposits by a focused ion beam SEM (FIB-SEM) and their atomic arrangements using a high angle angular dark filed scanning transmission electron microscopy (HAADF-STEM), as shown in Fig. 3 a-f. Study areas were selected on the dendritic and smooth surfaces of Cd deposits (insets of Fig. 3a, d), then cross-sectioned perpendicular to the substrates (Supplementary Fig. 12). The polycrystalline structures with multi-boundaries were observed in Cd dendrite (1M), which indicated that the dendritic growth is accompanied by the formation new grain boundary and its subsequent grain growth (Fig. 3a). In addition, the HAADF-STEM images of adjacent areas of 1 and 2 (Fig. 3a) revealed discontinuous atomic arrangement (Fig. 3b, c). This denotes different growth directions of Cd grains, which is the root of dendrite formation and growth. In contrast, the large micron-size cross section of Cd deposit (1M6M) exhibited a single crystalline structure, as no grain boundary was detected (Fig. 3d). Furthermore, the HAADF-STEM image revealed a uniform hexagonal close-packed (HCP) atomic arrangement (Fig. 3e), on which Cd atoms can grow continuously and uniformly in a layer-by-layer manner, “abababab”, resulting in the densest atomic packing (Fig. 3f). Therefore, this grain growth pattern prevents the formation of new grain boundaries and, consequently, dendrite growth. We subsequently quantified the charge-transfer kinetics in 1M and 1M6M electrolytes, by measuring the exchange current densities of Cd//Cd symmetric cells (Fig. 3g and Supplementary Fig. 13). Interestingly, the exchange current density in the 1M6M electrolyte is 3-fold higher than that the 1M electrolyte, reaching to 51.7 mA cm −2 . Moreover,the 1M6M electrolyte exhibited an ultrahigh ionic conductivity of ~550 mS cm −1 , researching a level comparable to that of H + /OH − conduction in aqueous medias 28 and significantly superior to that of the 1M electrolyte (Fig. 3h). These results indicated the much faster kinetics of charge transfer and [CdCl 4 ] 2− desolvation to Cd 2+ in 1M6M electrolyte than that of the charge transfer and the desolvation of hydrated Cd 2+ to Cd 2+ in 1M electrolyte (Fig. 3i). Therefore, this obvious difference in kinetics in 1M and 1M6M electrolytes contributed the inherently different Cd plating behaviors, one a kinetics-limited system and one a fast-kinetics system. Specially, the kinetics-limited 1M system could maintain the regular grain growth up to an areal capacity of 3 mAh cm −2 , but resulted in the dendritic growth at a high areal capacity of 5 mAh cm −2 (Supplementary Fig. 9). It indicated that the relatively slow kinetics of charge transfer and desolvation cannot keep up with the rapid and continuous depletion of Cd 2+ in the interfacial layer between electrode and electrolyte as the plated areal capacity increases, thereby disrupting the thermodynamic equilibrium necessary for complete Cd grain growth (Fig. 3i). 29,30 Consequently, it became a kinetics-limited Cd growth process, readily inducing the formation of new grain boundaries and subsequent irregular grain growth. 30,31 In contrast, in the 1M6M system, the ultrafast charge transfer and desolvation enabled the Cd growth process to proceed without kinetic limitations, resulting in a controlled and regular grain growth behavior (Fig. 3i). Therefore, it addressed the dendritic issue under deep cycling of battery. Corrosion-resistant Cd anode In addition to being free from dendritic issue, the corrosion-resistant capability of the metal anode is also paramount for long-term energy storage applications. 22 Notably, the highest aging CE has highlighted the high corrosion-resistant capability of ACBs (Fig. 2j). To further deep study this characteristic, we employed 3 M H 2 SO 4 for additional verification (Fig. 4a). Unlike metallic Zn, which underwent rapid chemical corrosion, gas evolution, and eventual complete dissolution in acidic solution, metallic Cd exhibited high resistance to chemical corrosion and retained its intact macro and micro morphologies. However, in a real aqueous environment, the corrosion scenario becomes significantly more complex due to the added factor of electrochemical corrosion. 32,33 We found that since the redox potential of Cd 2+ /Cd is slightly lower than that of the HER, the Cd anode still faces the risk of electrochemical corrosion (Fig. 4b). We subsequently used the symmetric cells to magnify this risk at continuous current fluctuations of 0.5 mA cm −2 to induce HER, as shown in Fig. 4c. 34,35 Given the markedly lower redox potential of Zn 2+ /Zn couple compared to HER (Fig. 4b), the Zn//Zn symmetric cell consistently experienced corrosion reactions and thus formed the byproduct of Zn 4 SO 4 (OH) 6 ·H 2 O (Supplementary Fig. 14), manifesting in cell polarization and eventual failure after only 45 h (Fig. 4c). In contrast, the Cd//Cd symmetric cells exhibited superior corrosion-resistant capability in both 1M and 1M6M electrolytes, as evidenced by their stable and extremely low voltage fluctuations over 229 h (Fig. 4c). However, byproducts were still detected in 1M electrolyte system during amplified corrosion process, in contrast to smooth Cd anode in 1M6M electrolyte, appearing as fine crystalline Cd(OH)Cl particulates adhering to the Cd anode surface (Supplementary Fig. 15) due to the HER of hydrated Cd 2+ to form Cd(OH)Cl and H 2 . Considering that amorphous or minimal amounts of byproducts may not be detected by XRD, more quantitative analysis using X-ray photoelectron spectroscopy (XPS) revealed the depth-profiled composition throughout the Cd anode surface (Fig. 5d, e). Compared to the Cd anode in 1M, only superficial layers of bare Cd anode and Cd anode in 1M6M contained O 1s signals, which can be deconvoluted into Cd-OH and Cd-O bands (Fig. 5d). We attributed the presence of these signs to slight oxidation by air (Bare Cd and Cd in 1M6M) or very weak electrochemical corrosion (Cd in 1M6M). Therefore, these signs disappeared after Ar + sputtering to the depths of 40 nm and 200 nm. However, notable O 1s signals corresponding to Cd-OH and Cd-O bonds were consistently detected on the surface of the Cd anode (1M) from a sputtering depth of 0 nm to 200 nm. Similar results were confirmed by the Cl 2p signals corresponding Cd-Cl bands (Fig. 5i), in which these notable signals were present on the Cd surface (1M) at various depths but only existed in the superficial layer of the Cd surface (1M6M). Consequently, our amplified corrosion experiments and the comprehensive characterizations demonstrated that the Cd anode in the 1M6M electrolyte is highly resistant to corrosion reactions. Given the variations in the local environment from 1M electrolyte to 1M6M electrolyte, we suggested that the replacement of H 2 O molecules by Cl − for hydrated Cd 2+ to [CdCl 4 ] 2− significantly weakened the HER, thereby favoring the dominance of Cd 2+ desolvation and subsequent deposition behaviors. Electrochemical performance of ACBs The electrochemical performance of ACBs was assessed using representative and commercial cathode materials, including coordination-type PANI, capacitance-type AC and intercalation-type V 2 O 5 , paired with the durable Cd anode. Cyclic voltammetry (CV) profiles were first collected to study the electrochemical behaviors of Cd//PANI full cell (Fig. 5a). The cell in the 1M6M electrolyte exhibited the relatively higher response current and reduction potential, indicating faster reaction kinetics and lower overpotential. Corresponding electrochemical impedance spectroscopy (EIS) demonstrated the smaller charge transfer impedance in the cell in 1M6M electrolyte (Supplementary Fig. 16). Furthermore, the rate performance of Cd//PANI full cells in 1M6M electrolyte showed a discharge capacity of 136 mAh g −1 at a low current density of 1 mA cm −2 , which is lightly higher than the cell in 1M electrolyte (Fig. 5b, c). However, this performance difference widened as the current density increased. The cell in the 1M6M electrolyte still exhibited an applicable discharge capacity of 75 mAh g −1 at a high current density of 50 mA cm −2 , whereas, in the 1M electrolyte, the discharge capacity of cell decreased to 54 mAh g −1 . This suggested that the full cell in the 1M6M electrolyte exhibited faster charge transfer and reaction kinetics compared to the cell in the 1M electrolyte. This result was further confirmed by the high exchange current of full cell with the 1M6M electrolyte (Supplementary Fig. 17), indicating the capability of ACBs for high-rate performance. Furthermore, long-term rechargeable capability of Cd//PANI full cells was evaluated at different high rates (denoted 130 mA g −1 as 1 C rate), as shown in Fig. 5d, e and Supplementary Fig. 18. It should be noted that although high rates are typically used in aqueous batteries to achieve extended cycle life, rechargeability at low rates remains significantly limited yet necessary. 27,36 However, in our work, the full cell demonstrated its excellent low-rate rechargeable capability at 1.12 C, showing a high capacity retention rate of about 80% after 1,000 cycles (Fig. 5d). Furthermore, at a superhigh rate of 50.34 C, the full cell exhibited exceptional rechargeable capability, retaining 83% of its initial capacity after 20,000 cycles (Fig. 5e), which meets the high-power demands of large-scale energy storage applications. On the other hand, the ACBs demonstrated their high compatibility for multi-scenario application, as confirmed by pairing the Cd anode with capacitance-type AC and intercalation-type V 2 O 5 cathodes. The Cd//AC capacitor showed typical characteristic of electronic double layer capacitors with large response currents at scan rates from 20 to 100 mV s −1 and performed excellent rechargeability with a capacity retention of about 90% upon 10,000 charging/discharging cycles (Supplementary Fig. 19). Attractively, the ACB with intercalation-type V 2 O 5 cathode also performed stable cycling with a high discharge capacity of 270 mAh g −1 after 100 cycles (Supplementary Fig. 20). From an application perspective, the use of a thin Cd anode with high utilization under deep cycling conditions is essential for practical energy storage infrastructures. Here, we further assembled the Cd//PANI full cell with a high-load cathode of 38.22 mg cm −2 and a low N/P ratio of 1.91 (anode capacity: 9.09 mAh cm −2 ). As shown in Supplementary Fig. 21a, the high-load full battery using 1M electrolyte could only run for 4 cycles before experiencing a sudden internal short circuit. In contrast, a significantly longer lifespan of 800 cycles was achieved in the full cell using 1M6M electrolyte, with a high cumulative areal capacity of 2.57 Ah cm - 2 (Fig. 5f). Additionally, this high-load and low N/P full cell in 1M6M electrolyte, with a 12-hour rest period per cycle, exhibited a low self-discharge rate of only 5.4% after the first charge to 1.1 V, which further decreased to 2.4% after the twentieth charge to 1.1 V (Fig. 5g, h and Supplementary Fig. 21b). This demonstrated its capability for intermittent usage in practical applications. Conclusion In summary, beyond the existing but problematic aqueous metal batteries, we developed a more reliable ACB. We disclosed this ACB operating with a low-cost and quasi-neutral CdCl 2 + NH 4 Cl electrolyte, where the reconstructed hydrogen bond network and formed [CdCl 4 ] 2 - confer the fast kinetics to the ACBs. More importantly, the proposed ACBs addressed the two issues commonly found in metallic anode-based batteries: dendritic growth and anode corrosion. Therefore, it enabled the Cd anode perform the convincing CE of 99.93% and aging CE of 99.34% for plating/stripping behaviors at a high AU of 55% (5 mAh cm -2 ). In addition, the proposed ACB exhibited outstanding compatibility with different types of cathode materials, e.g. , PANI, AC and V 2 O 5 . On a practical note, we demonstrated that the ACB with a high-load cathode of 38.22 mg cm –2 and a low N/P of 1.91 sustained a high rechargeability over 800 cycles and showed a low self-discharge rate. Therefore, the proposed ACB revitalizes the concept of aqueous metal batteries, and the convincing results highlight its potential for commercialization Declarations Acknowledgements This research/project is supported by the Ministry of Education, Singapore, under its SUTD Kickstarter Initiative (SKI 2021_04_14). 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Wang, J & Sun Y. Anode corrosion in aqueous Zn metal batteries. eScience 3 , 100093 (2023). Cui, Y. et al. A high-voltage and stable zinc-air battery enabled by dual-hydrophobic-induced proton shuttle shieldin. Joule 6 , 1617–1631 (2022). Jiang, H. et al. Chloride electrolyte enabled practical zinc metal battery with a near-unity Coulombic efficiency. Nat. Sustain. 6 , 806–815 (2023). Cao, L. et al. Fluorinated interphase enables reversible aqueous zinc battery chemistries. Nat. Nanotechnol. 16 , 902–910 (2021). Cui, Y.-F. et al. A dendrite-free and anticaustic Zn anode enabled by high current-induced reconstruction of electrical double layer. Chem. Commun. 59, 2437–2440 (2023). Methods Materials Cadmium chloride (CdCl 2 , 99.99%), ammonium chloride (NH 4 Cl, 99.99), Zinc sulfate heptahydrate (ZnSO 4 ·7H 2 O, 99%), isopropanol (anhydrous, 99.5%), vanadium (V) oxide (V 2 O 5 , 99.95%), polyaniline (PANI) and sulfuric acid (H 2 SO 4 , 95%~97%) were obtained from Sigma Aldrich. Cd foil (99.9%), Zn foil (99.9%) and polytetrafluoroethylene (PTFE) aqueous dispersion solution were obtained from the supplier of SCI Materials Hub. Activated carbon (AC, YP80F), conductive carbon (Ketjen black; KB), copper foil, titanium (Ti) mesh and graphite were obtained from the Canrd New Energy Technology. Preparation of electrodes Cd and Zn anodes preparation: metallic anodes were achieved by continuously rolling of commercial Zn and Cd foils through a roll press (MSK-2150-H5) until a mass of about 11 mg cm - 2 for Zn foil and about19 mg cm - 2 for Cd foil were attained, which were subsequently cut into circular foils with a diameter of 1 cm for anode usage. V 2 O 5 cathode preparation: the commercial V 2 O 5 and graphite with a mass ratio of 8: 2 were filled into the ball-milling jar and their mixture was ball milled at 500 rpm for 480 min. Subsequently, the V 2 O 5 cathode was prepared by uniformly grinding the ball-milled V 2 O 5 /graphite mixture, KB and PTFE in a mass ration of 8: 1: 1 in isopropanol solvent. Finally, the material mixture was pressed into Ti mesh and dried in the vacuum oven at 80 °C for 8 h. Preparation of PANI and AC cathodes: the PANI cathode was prepared by uniformly grinding the commercial PANI, KB and PTFE in a mass ration of 7: 2: 1 in isopropanol solvent. Finally, the material mixture was pressed into Ti mesh and dried in the vacuum oven at 80 °C for 8 h. Preparation of AC cathode is similar to PANI cathode, where the difference lies in the mass ration of AC: KB: PTFE is 8: 1: 1. Finally, all the cathodes were cut into circular electrodes with a diameter of 1 cm. Fabrication of the cells. All cells were assembled using two-electrode Swagelok-type configurations, supported by SCI Materials Hub, where two electrodes (Zn and Zn, Cd and Cd, Zn and Cu, Cd and Cu, Cd and PANI, Cd and V 2 O 5 , or Cd and AC) were separated by glass fibre (GF/A, Whatman) using electrolytes (2ZS, 1M or 1M6M electrolyte) of about 80 μL. Materials characterizations 1 H nuclear magnetic resonance ( 1 H NMR) and 17 O nuclear magnetic resonance ( 17 O NMR) were conducted on a Bruker ( AVANCE III, HD 500 MHz) NMR spectrometer. The NMR spectra were calibrated to an internal capillary tube containing D 2 O within NMR tube. Scanning electron microscopy (SEM, JEOL JSM-7600F) equipment was used to investigate the microstructure. Fourier transform infrared spectroscopy (FTIR) spectra was recorded using a Thermo (Nicolet 6700) system with a resolution of 4 cm - 1 . X-ray diffraction (XRD) patterns were collected on a Bruker D8 Advanced X-ray diffractometer with Cu Kα radiation. X-ray photoelectron spectroscopy (XPS) tests were performed on an XPS instrument (PHI, Model 5600). The Ar + sputtering rate was estimated to be about 5 nm min - 1 . The high/low frequency Raman data were carried out by a Raman spectroscopy (Horiba LabRAM HR Evolution) using a laser with a wavelength of 532 nm. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) mode was conducted on JEM-ARM200F NeoARM with a spherical aberration corrector at 200 kV. HAADF-STEM samples were prepared using a focused ion beam (FIB) of FIB-SEM (ZEISS Crossbeam 540). Electrochemical measurements All the electrochemical data were obtained from the two-electrode Swagelok-type configurations. Electrochemical impedance spectroscopy (EIS) was performed over a frequency range of 1 MHz to 10 mHz at an AC amplitude of 10 mV. EIS and Cyclic voltammetry (CV) profiles were collected by a Biologic VMP3 system. Charge-discharge with/without aging process tests of the Zn//Zn symmetric cells, Cd//Cd symmetric cells, Zn//Cu cells, Cd//Cu cells, Cd//PANI full cells, Cd//AC full cells, Cd//V 2 O 5 full cells, and high-load Cd//PANI full cells were carried out using the galvanostatic method on a multichannel Neware instrument. All the detailed electrochemical test conditions, including current density, areal capacity, load mass of electrodes, and N/P ratio, were given in the Manuscript and Supplementary Information. Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.docx Supplementary Information to the Article Cite Share Download PDF Status: Published Journal Publication published 01 Jul, 2025 Read the published version in Nature Communications → 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-4646240","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Physical Sciences - Article","associatedPublications":[],"authors":[{"id":327781939,"identity":"fbd121f5-70ef-4a08-8ea2-f9d2ab71de15","order_by":0,"name":"Hui Ying 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Zhu","email":"","orcid":"https://orcid.org/0000-0002-2333-2740","institution":"Wuhan Textile University","correspondingAuthor":false,"prefix":"","firstName":"Yunhai","middleName":"","lastName":"Zhu","suffix":""}],"badges":[],"createdAt":"2024-06-27 06:05:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4646240/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4646240/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41467-025-60740-2","type":"published","date":"2025-07-01T04:00:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":61926717,"identity":"f93ade90-fcab-4797-af62-4984dac903ff","added_by":"auto","created_at":"2024-08-07 07:17:58","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":753204,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eProposed ACBs for next-generation energy storage infrastructures.\u003c/strong\u003e \u003cstrong\u003ea,\u003c/strong\u003e Schematic of redox potentials, specific capacities and characteristics of different electrodes in aqueous electrolytes. \u003cstrong\u003eb,\u003c/strong\u003e Advantages of Cd anode compared to Zn anode. \u003cstrong\u003ec,\u003c/strong\u003eSchematic diagram of the proposed ACBs. \u003cstrong\u003ed,\u003c/strong\u003e Advantages of ACBs compared to AZBs.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4646240/v1/78e1dc5a4534170edf510ab8.png"},{"id":61926721,"identity":"cff1839e-e69e-4d58-8bc3-ec841e192773","added_by":"auto","created_at":"2024-08-07 07:17:59","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":826499,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFundamentals and electrochemistry of aqueous chloride electrolyte.\u003c/strong\u003e \u003cstrong\u003ea\u003c/strong\u003e-\u003cstrong\u003ec\u003c/strong\u003e, FTIR spectra (\u003cstrong\u003ea\u003c/strong\u003e), Raman spectra in high frequency (\u003cstrong\u003eb\u003c/strong\u003e), and Raman spectra in low frequency (\u003cstrong\u003ec\u003c/strong\u003e) in different electrolytes. \u003cstrong\u003ed\u003c/strong\u003e, Schematic structure of aqueous CdCl\u003csub\u003e2\u003c/sub\u003e + NH\u003csub\u003e4\u003c/sub\u003eCl electrolyte. \u003cstrong\u003ee\u003c/strong\u003e, Average CE and cycle number in different electrolytes at 2 mA cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e and 3 mAh cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e with AU of 33%.\u003cstrong\u003e f\u003c/strong\u003e, CEs of Cd and Zn plating/stripping behaviors in different electrolytes measured at 10 mA cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e and 5 mAh cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e with AU of 55%. \u003cstrong\u003eg\u003c/strong\u003e, SEM image of Cd anode in 1M6M electrolyte after 10 cycles. \u003cstrong\u003eh\u003c/strong\u003e-\u003cstrong\u003ek, \u003c/strong\u003eAging CE test sequence (\u003cstrong\u003eh\u003c/strong\u003e), the corresponding voltage profiles in 1M6M electrolyte (\u003cstrong\u003ei\u003c/strong\u003e), aging CEs in different electrolytes (\u003cstrong\u003ej\u003c/strong\u003e), and Cd plating/stripping curves in 1M6M electrolyte (\u003cstrong\u003ek\u003c/strong\u003e). Aging CE performed at a fixed plated capacity of 5 mAh cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e and current density of 5 mA cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e, an aging time of 12 h, and then a stripped current density of 5 mA cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e for per cycle with AU of 55% (\u003cstrong\u003eh\u003c/strong\u003e-\u003cstrong\u003ek\u003c/strong\u003e).\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4646240/v1/1183e662e6f67b0f0dd355c5.png"},{"id":61927336,"identity":"1b920e43-68b9-4062-8d55-d15cc92138ce","added_by":"auto","created_at":"2024-08-07 07:25:58","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":937877,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eKinetics-controlled Cd plating behavior.\u003c/strong\u003e \u003cstrong\u003ea\u003c/strong\u003e, \u003cstrong\u003ed\u003c/strong\u003e, FIB-SEM images of cross-section Cd deposits in 1M electrolyte (\u003cstrong\u003ea\u003c/strong\u003e) and 1M6M electrolyte (\u003cstrong\u003ed\u003c/strong\u003e) at a current density of 10 mA cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2 \u003c/sup\u003eand areal capacity of 5 mAh cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e.\u003cstrong\u003e \u003c/strong\u003eInserts: SEM images of original Cd deposits. \u003cstrong\u003eb\u003c/strong\u003e, \u003cstrong\u003ec\u003c/strong\u003e, HAADF-STEM images of Cd deposits in 1M electrolyte with FFT inset. \u003cstrong\u003ee\u003c/strong\u003e, \u003cstrong\u003ef\u003c/strong\u003e, HAADF-STEM images of Cd deposit in 1M6M with a FFT inset (\u003cstrong\u003ee\u003c/strong\u003e) and atom growth mechanism in 1M6M (\u003cstrong\u003ef\u003c/strong\u003e). \u003cstrong\u003eg\u003c/strong\u003e,\u003cstrong\u003e h\u003c/strong\u003e, Exchange current densities (\u003cstrong\u003eg\u003c/strong\u003e) and ionic conductivity (\u003cstrong\u003eh\u003c/strong\u003e) in 1M and 1M6M electrolytes. \u003cstrong\u003ei\u003c/strong\u003e, Schematic of kinetics-controlled Cd plating behaviors.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4646240/v1/37d7ed4894db41625a3f5166.png"},{"id":61926720,"identity":"d2a61378-1a48-4a37-89aa-41478f632e23","added_by":"auto","created_at":"2024-08-07 07:17:59","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":929577,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCorrosion-resistant Cd anode.\u003c/strong\u003e \u003cstrong\u003ea\u003c/strong\u003e, Chemical corrosion of Cd and Zn anodes in 3 M H\u003csub\u003e2\u003c/sub\u003eSO\u003csub\u003e4\u003c/sub\u003e solution, and the corresponding SEM images of Cd anodes. \u003cstrong\u003eb\u003c/strong\u003e, Simplified Pourbaix diagram of Cd, Zn and H\u003csub\u003e2\u003c/sub\u003eO. \u003cstrong\u003ec\u003c/strong\u003e, Voltage curves of Zn//Zn and Cd//Cd symmetric cells in different electrolytes at 0.5 mA cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e and 0.1 mAh cm\u003csup\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e. \u003cstrong\u003ed\u003c/strong\u003e, \u003cstrong\u003ee\u003c/strong\u003e, XPS spectra of Cd anodes before and after cycling 229h with depth\u003cstrong\u003e \u003c/strong\u003eprofiles of O 1s (\u003cstrong\u003ed\u003c/strong\u003e) and Cl 2p (\u003cstrong\u003ee\u003c/strong\u003e).\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-4646240/v1/7697b6149678b329aaa34e79.png"},{"id":61928074,"identity":"6c7bb782-34d3-48dd-b7cb-ffce4bc1abae","added_by":"auto","created_at":"2024-08-07 07:33:59","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":525864,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eElectrochemical performance of Cd//PANI full cells.\u003c/strong\u003e \u003cstrong\u003ea,\u003c/strong\u003e CV curves of 5 cycles at a scan rate of 2 mV s\u003csup\u003e−1\u003c/sup\u003e in 1M and 1M6M electrolytes. \u003cstrong\u003eb\u003c/strong\u003e, \u003cstrong\u003ec\u003c/strong\u003e, Discharge specific capacities (\u003cstrong\u003eb\u003c/strong\u003e) and corresponding charge/discharge curves (\u003cstrong\u003ec\u003c/strong\u003e) at different current densities in 1M and 1M6M electrolytes. \u003cstrong\u003ed\u003c/strong\u003e, \u003cstrong\u003ee\u003c/strong\u003e, Cycling performance at 1.12 C (\u003cstrong\u003ed\u003c/strong\u003e) and 50.34 C (\u003cstrong\u003ee\u003c/strong\u003e) in 1M6M electrolyte. \u003cstrong\u003ef\u003c/strong\u003e, Cycling performance at 10 mA cm\u003csup\u003e−2\u003c/sup\u003e with a high-load cathode (38.22 mg cm\u003csup\u003e−2\u003c/sup\u003e) and low N/P (1.91). \u003cstrong\u003eg\u003c/strong\u003e, \u003cstrong\u003eh\u003c/strong\u003e, Voltage curves of intermittent usage in a full cell with a high-load cathode (38.22 mg cm\u003csup\u003e−2\u003c/sup\u003e) and low N/P rate (1.91) at 5 mA cm\u003csup\u003e−2\u003c/sup\u003e and interval 12 h (\u003cstrong\u003eg\u003c/strong\u003e), and the corresponding CE in 1M and 1M6M electrolytes (\u003cstrong\u003eh\u003c/strong\u003e).\u003cbr\u003e\n\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4646240/v1/404575cb5cfffbfb5dd25cff.png"},{"id":85826635,"identity":"6ae4adb5-5fa5-47bb-9f45-928760d42c96","added_by":"auto","created_at":"2025-07-02 07:15:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5583576,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4646240/v1/39ba1fef-3812-409e-b2ae-04ae4bdba3fc.pdf"},{"id":61926722,"identity":"a82e8298-b604-4f66-9498-214eef2f637a","added_by":"auto","created_at":"2024-08-07 07:17:59","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":8372752,"visible":true,"origin":"","legend":"Supplementary Information to the Article","description":"","filename":"SupplementaryInformation.docx","url":"https://assets-eu.researchsquare.com/files/rs-4646240/v1/e569026146e9c1241b246265.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Fast-kinetics and high-compatibility aqueous cadmium-metal battery for next-generation energy storage infrastructures","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe transition from carbon-rich fossil fuels to environmentally friendly renewable energy sources to achieve decarbonization has become a fundamental goal across academia, industry, and government.\u003csup\u003e1\u003c/sup\u003e However, the increasing reliance on renewable but intermittent energy sources—such as solar, wind, and tidal power—necessitates the development of cost-effective, safe, and durable energy storage solutions capable of storing large amounts of electrical energy.\u003csup\u003e2\u003c/sup\u003e While lithium-ion batteries have successfully dominated the market for applications requiring high energy density, they may not be the optimal choice for all scenarios, particularly for grid-scale energy storage, due to the use of flammable organic electrolytes and scarce electrode materials.\u003csup\u003e3\u003c/sup\u003e In contrast, aqueous metal batteries have emerged as promising candidates in various energy storage contexts, offering high power density, fast-charging capability, minimized safety risks, and lower manufacturing costs.\u003csup\u003e4\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eHowever, the current problem lies in the absence of convincing aqueous energy storage systems capable of supporting the decarbonization of renewable electricity generation.\u0026nbsp;This explains why century-old lead-acid batteries with a low energy density (30-50 Wh kg\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e) remain indispensable in grid-scale energy storage, portable electronics, and electric vehicles.\u003csup\u003e5,6\u003c/sup\u003e In recent years, rechargeable aqueous zinc-metal batteries (AZBs) have been considered promising candidates for multi-scenario storage applications.\u003csup\u003e7,8\u003c/sup\u003e The metallic zinc (Zn) is one of the few metal anodes capable of reversible plating/stripping behavior in aqueous medias while offering a suitable redox potential (-0.76 V vs. standard hydrogen electrode, SHE) and high specific capacity (820 mAh g\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e), as shown in Fig. 1a. AZBs fitted with manganese (Mn)-based, vanadium (V)-based, and organic cathodes are attractive for their high theoretical specific energy (60-250 Wh kg\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e).\u003csup\u003e9\u003c/sup\u003e However, the fatal issues of cell shorting by dendrites and passivation due to corrosion have hindered the deployment of this technology.\u003csup\u003e10,11\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eMotivated by this background, several emerging metal anodes are being explored to replace Zn anodes, such as iron (Fe), indium (In), nickel (Ni), tin (Sn), copper (Cu), and bismuth (Bi). While these metal anodes exhibit impressive electrochemical properties, they face intrinsic limitations for next-generation energy storage applications (Fig. 1a). For instance, Fe anodes suffer from passivation reactions that block ionic shuttling.\u003csup\u003e12\u003c/sup\u003e In is a rare and noble metal, making it unsuitable for large-scale energy storage.\u003csup\u003e13\u003c/sup\u003e The plating/stripping behavior of Ni anode experiences sluggish kinetics, resulting in high potential polarization.\u003csup\u003e14,15\u003c/sup\u003e The redox potentials of the Cu\u003csup\u003e2+\u003c/sup\u003e/Cu (+0.34 V vs. SHE) and Bi\u003csup\u003e3+\u003c/sup\u003e/Bi (+0.32 V vs. SHE) couples are too high for practical use in batteries.\u003csup\u003e16,17\u003c/sup\u003e In contrast, acidic Sn-metal batteries paired with acidic cathodes seem to be a more promising candidate. However, the use of an ion exchange membrane to separate the anode electrolyte and cathode electrolyte, thereby preventing Sn\u003csup\u003e2+\u003c/sup\u003e shuttle and the subsequent redox reactions of Sn\u003csup\u003e3+\u003c/sup\u003e/Sn\u003csup\u003e2+\u003c/sup\u003e at the cathode surface, is a prerequisite for the proper functioning of this battery.\u003csup\u003e18\u003c/sup\u003e It results in that the energy density of acidic Sn-metal battery actually depends on the concentration of H\u003csup\u003e+\u003c/sup\u003e and solubility of discharge products\u0026nbsp;in electrolytes and the use of ion exchange membranes increases the manufacturing costs.\u003c/p\u003e\n\u003cp\u003eTo overcome these issues, we report an ideal alternative to existing aqueous metal batteries: the aqueous cadmium-metal battery (ACB). Herein,\u0026nbsp;the metallic cadmium (Cd) anode not only possesses the dendrite-free and corrosion-resistant capabilities but also exhibits a high specific capacity (476.5 mAh g\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e) and a suitable redox potential (-0.4 V vs. SHE), as shown in Fig 1a. Consequently, this gives Cd anode comprehensive advantages over other metal anodes, especially the Zn anode (Fig. 1a, b).\u0026nbsp;Additionally, we disclose this ACB operating with a low-cost chloride electrolyte composed of 1 M CdCl\u003csub\u003e2\u003c/sub\u003e + 6 M NH\u003csub\u003e4\u003c/sub\u003eCl in water.\u0026nbsp;The introduction of NH\u003csub\u003e4\u003c/sub\u003eCl reconstructs the hydrogen bond network among H\u003csub\u003e2\u003c/sub\u003eO molecules and forms tetrachlorocomplex, [CdCl\u003csub\u003e4\u003c/sub\u003e]\u003csup\u003e2\u003c/sup\u003e\u003csup\u003e-\u003c/sup\u003e species. This restructuring facilitates the ultrafast charge-transfer, desolvation and reaction kinetics in ACB, while concurrently suppressing the corrosion reaction\u0026nbsp;and contributing to smooth Cd plating/stripping behaviors.\u0026nbsp;Consequently, the tailored electrolyte enables convincing Coulombic efficiency (CE) of 99.93% and the highest aging CE of 99.34% for Cd plating/stripping behaviors at a high anode utilization (AU) of 55.5% (5 mAh cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e). This practical performance makes numerous high-energy and durable aqueous batteries based on Cd anodes feasible, including but not limited to Cd//MnO\u003csub\u003e2\u003c/sub\u003e cells, Cd//V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e cells, Cd//organic cells, Cd-air cells, and hybrid Cd-ion capacitors (Fig. 1c, d). Their diversity and universality are confirmed by using three types of representative cathodes, intercalation-type V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e, capacitance-type active carbon (AC) and coordination-type organic polyaniline (PANI). Specially, the high-load Cd//PANI full cell delivers a stable cycling performance over 800 cycles, with a negative-to-positive capacity (N/P) ratio of 1.91 and a cumulative areal capacity of 2.57 Ah cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e. Overall, our work suggests a practical ACB capable of supporting robust energy storage infrastructures.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eFundamentals of aqueous chloride electrolytes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIt is known that NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e in aqueous solution shares many similar properties with H\u003csub\u003e2\u003c/sub\u003eO,\u003csup\u003e19,20\u003c/sup\u003e and can form hydrogen bonds with four H\u003csub\u003e2\u003c/sub\u003eO molecules.\u003csup\u003e21\u003c/sup\u003e On the other hand, in dilute electrolytes, cations tend to be solvated by polar H\u003csub\u003e2\u003c/sub\u003eO molecules to form the hydrated cations.\u003csup\u003e22\u003c/sup\u003e Based on these fundamental properties, our strategy involves introducing NH\u003csub\u003e4\u003c/sub\u003eCl as a supporting salt in a dilute CdCl₂ solution to reconstruct the hydrogen bond network among H\u003csub\u003e2\u003c/sub\u003eO molecules and modify the aqua ligands of Cd\u003csup\u003e2+\u003c/sup\u003e through the extra Lewis base of Cl\u003csup\u003e-\u003c/sup\u003e from NH\u003csub\u003e4\u003c/sub\u003eCl, aiming to reduce water activity without compromising the original advantages of the dilute electrolyte. Starting with the baseline electrolyte of 1 M CdCl\u003csub\u003e2\u003c/sub\u003e (referred to as 1M), we first examined the electrolyte structure of adding different concentrations of NH\u003csub\u003e4\u003c/sub\u003eCl (1 M CdCl\u003csub\u003e2\u003c/sub\u003e + 1 M NH\u003csub\u003e4\u003c/sub\u003eCl, 1 M CdCl\u003csub\u003e2\u003c/sub\u003e + 2 M NH\u003csub\u003e4\u003c/sub\u003eCl, 1 M CdCl\u003csub\u003e2\u003c/sub\u003e + 4 M NH\u003csub\u003e4\u003c/sub\u003eCl, 1 M CdCl\u003csub\u003e2\u003c/sub\u003e + 6 M NH\u003csub\u003e4\u003c/sub\u003eCl, and 1 M CdCl\u003csub\u003e2\u003c/sub\u003e + 7.5 M NH\u003csub\u003e4\u003c/sub\u003eCl electrolytes referred to as 1M1M, 1M2M, 1M4M, 1M6M, and 1M7.5M, respectively). In Fig. 2a, Fourier transform infrared spectroscopy (FTIR) at the 1100 cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e band of NH\u003csub\u003e3\u003c/sub\u003e was absent in the spectra of all NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-containing electrolytes. This indicated that the hydrolysis behavior of NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e to produce NH\u003csub\u003e3\u003c/sub\u003e·H\u003csub\u003e2\u003c/sub\u003eO and H\u003csup\u003e+\u003c/sup\u003e can be considered negligible.\u003csup\u003e23\u003c/sup\u003e In contrast, the peak of NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e appeared at 1440 cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u0026nbsp;\u003c/sup\u003eband and became increasingly prominent with higher concentrations of NH\u003csub\u003e4\u003c/sub\u003eCl. They existed in aqueous solution as hydrated NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e, which is confirmed by the presence of hydrogen bond between NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e and H\u003csub\u003e2\u003c/sub\u003eO, indicated by the bands at 3360, 3200, and 3050 cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e in the spectra.\u003csup\u003e23,24\u003c/sup\u003e The impact of NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e on the hydrogen bond network of H\u003csub\u003e2\u003c/sub\u003eO molecules were analyzed through Raman spectra (Fig. 2b), wherein the O-H stretching for H\u003csub\u003e2\u003c/sub\u003eO molecules in the high-frequency range were deconvoluted into three peaks corresponding to the strongly, weakly, and slightly hydrogen-bonded components at the peaks of 3248.9, 3468.4, and 3628.8 cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e (Supplementary Fig. 1).\u0026nbsp;From pure water to 1M7.5M electrolyte, the hydrogen networks of H\u003csub\u003e2\u003c/sub\u003eO molecules gradually transitioned from the strong hydrogen bond-dominated conformation to the weak hydrogen bond-dominated conformation; meanwhile, the peak intensity corresponding to NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e at the peaks of 2878.7, 3032.1, and 3115.0 cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e gradually increased (Fig. 2b and Supplementary Fig. 1). They demonstrated that the introduction of NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e into the 1M electrolyte disrupted the original hydrogen bond environment among H\u003csub\u003e2\u003c/sub\u003eO molecules and subsequently participated in forming a new hydrogen bond network between NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e and H\u003csub\u003e2\u003c/sub\u003eO as hydrate NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e. Furthermore, as the concentration of NH\u003csub\u003e4\u003c/sub\u003eCl increased, the shifts of \u003csup\u003e1\u003c/sup\u003eH nuclear magnetic resonance (\u003csup\u003e1\u003c/sup\u003eH NMR) and \u003csup\u003e17\u003c/sup\u003eO NMR signals of H\u003csub\u003e2\u003c/sub\u003eO also indicated the enhanced hydrogen bond interactions between H\u003csub\u003e2\u003c/sub\u003eO and NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e as hydrated NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e but decreased hydrogen bond interactions among H\u003csub\u003e2\u003c/sub\u003eO molecules (Supplementary Fig. 2). Besides the NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-involved hydrogen bond network, we observed that the formation of tetrachlorocomplex, [CdCl\u003csub\u003e4\u003c/sub\u003e]\u003csup\u003e2−\u003c/sup\u003e, was confirmed at the peak of about 260 cm\u003csup\u003e−1\u003c/sup\u003e with the increased NH\u003csub\u003e4\u003c/sub\u003eCl concentration, as shown in the low-frequency Raman spectra of Fig. 2c.\u003csup\u003e25,26\u003c/sup\u003e This confirmed our design concept (Fig. 2d), where NH\u003csub\u003e4\u003c/sub\u003eCl provided extra Lewis base of Cl\u003csup\u003e−\u003c/sup\u003e that complexed with Lewis acid of Cd\u003csup\u003e2+\u003c/sup\u003e to transform the hydrated Cd\u003csup\u003e2+\u003c/sup\u003e to [CdCl\u003csub\u003e4\u003c/sub\u003e]\u003csup\u003e2−\u003c/sup\u003e. Note that this transformation addressed a series of side reactions initiated by hydrated cations, such as hydrogen evolution reaction (HER) and dendritic growth, as discussed later. Therefore, the NH\u003csub\u003e4\u003c/sub\u003eCl imparted versatility to dilute 1M electrolyte, involving rich NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-involved H-bond network and [CdCl\u003csub\u003e4\u003c/sub\u003e]\u003csup\u003e2−\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eElectrochemistry of Cd anodes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn our study aimed at developing practical energy storage infrastructures, we thus employed rigorous testing conditions to screen the tailored aqueous electrolytes.\u0026nbsp;This involved evaluating the CE of Cd plating/stripping behaviors at a substantial AU of 33% (3 mAh cm\u003csup\u003e−\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e), using a precise two-electrode Swagelok-type cell (Supplementary Figs. 3−5). Fig. 2e summarized the performance in different electrolyte. The average CE of Cd plating/stripping behaviors in 1M6M electrolyte was the highest and reached 99.89% (400 cycles), much higher than the average CE of 1M (99.76%) obtained from the reversible 129 cycles. It demonstrated the introduction of 6 M NH\u003csub\u003e4\u003c/sub\u003eCl significantly improved the performance of the Cd anode. Consequently, the 1M6M electrolyte was identified as the optimal choice for subsequent research. We further utilized Cd//Cu cells to assess the performance of the ACB at a higher AU of 55% (5 mAh cm\u003csup\u003e−2\u003c/sup\u003e) and a higher current density of 10 mA cm\u003csup\u003e−2\u003c/sup\u003e, aiming to meet the demanding requirements of practical applications.\u003csup\u003e27\u003c/sup\u003e The performance was compared against that of the baseline 1M electrolyte in the ACB and commonly used 2 M ZnSO\u003csub\u003e4\u003c/sub\u003e (2ZS) electrolyte in the AZB,\u003csup\u003e7\u003c/sup\u003e as depicted in Fig. 2f and Supplementary Fig. 6. An initial CE of 99.50% and an average CE of 99.93% over 300 cycles were achieved in 1M6M electrolyte, which reflect the highest Cd plating/stripping efficiency at a practical condition. By contrast, an initial CE of 98.89% and average CE of 99.86% within reversible 39 cycles were obtained in baseline 1M electrolyte, which are still obviously superior to the Zn plating/stripping efficiency of initial CE (94.20%) and average CE (98.51% within reversible 33 cycles). Furthermore, to figure out the highest reversibility of Cd anode in 1M6M electrolyte, we analyzed the anode morphologies after cycling by a scanning electron microscopy (SEM). It was observed that Cd anode in 1M6M electrolyte demonstrated dendrite-free capability with a smooth and dense morphology (Fig. 2g), thereby affording the excellently electrochemical performance.\u0026nbsp;In contrast, the Cd anode in 1M electrolyte showed randomly oriented plate-like deposits (Supplementary Fig. 7a), whereas the moss-like dendrites that more easily leads to cell shorting formed on the Zn anode (Supplementary Fig. 7b).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eConsidering that energy storage infrastructures necessarily involve intermittent usage in practical applications, we further evaluated the aging CE of restoring aging-induced anode in aqueous electrolyte under an extremely stringent condition, as shown in Fig. 2h. We observed that long-term storage of metal Cd in aqueous electrolytes did not lead to capacity loss caused by corrosion. This was evidenced by stable voltage polarization curves of plating, aging and stripping processes (Fig. 2i), high average CE of ~99.34 (Fig. 2j), and highly overlapping plating/stripping curves over cycles (Fig. 2k). To our knowledge, no current metal battery system demonstrated this capability, even under conditions of minimal anode utilization. For example, the promising Zn anode only achieved an aging CE of less 75% (Fig. 2j) and suffered from obvious voltage polarization-induced cell failure in second cycle due to capacity loss caused by corrosion of aqueous electrolyte (Supplementary Fig. 8a, b).\u003csup\u003e11\u003c/sup\u003e By the way, although Cd anode was cycled only 6 cycles in 1M electrolyte, its failure was not due to corrosion reaction but rather to cell shorting (Supplementary Fig. 8c, d). Additionally, it exhibited a high average aging CE of 97.58% (Fig. 2j). This further indicated that Cd anode is inherently corrosion-resistant in aqueous electrolytes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDendrite-free Cd plating/stripping behaviors\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo further validate the dendrite-free capability of ACB and exclude homogeneous effect during plating process, we investigated Cd plating/stripping behaviors on Cu foil substrate at a high areal capacity of 5 mAh cm\u003csup\u003e−2\u003c/sup\u003e.\u0026nbsp;The morphological evolutions were observed by ex-situ SEM (Supplementary Figs. 9−11). The Cd deposits in 1M electrolyte could maintain regular texture morphology up to 3 mAh cm\u003csup\u003e−2\u003c/sup\u003e, whereas, beyond this capacity, uncontrolled dendrites began to form and grow (Supplementary Fig. 9). In contrast, the plating process for Cd in 1M6M electrolyte consistently showed a regular grain growth process (Supplementary Fig. 10).\u0026nbsp;However, the Zn plating process was accompanied by the pronounced moss-like dendrite growth (Supplementary Fig. 11).\u003c/p\u003e\n\u003cp\u003eWe subsequently studied the cross-section morphologies of Cd deposits by a focused ion beam SEM (FIB-SEM) and their atomic arrangements using a high angle angular dark filed scanning transmission electron microscopy (HAADF-STEM), as shown in Fig. 3 a-f. Study areas were selected on the dendritic and smooth surfaces of Cd deposits (insets of Fig. 3a, d), then cross-sectioned perpendicular to the substrates (Supplementary Fig. 12). The polycrystalline structures with multi-boundaries were observed in Cd dendrite (1M), which indicated that the dendritic growth is accompanied by the formation new grain boundary and its subsequent grain growth (Fig. 3a). In addition, the HAADF-STEM images of adjacent areas of 1 and 2 (Fig. 3a) revealed discontinuous atomic arrangement (Fig. 3b, c).\u0026nbsp;This denotes different growth directions of Cd grains, which is the root of dendrite formation and growth. In contrast, the large micron-size cross section of Cd deposit (1M6M) exhibited a single crystalline structure, as no grain boundary was detected (Fig. 3d). Furthermore, the HAADF-STEM image revealed a uniform hexagonal close-packed (HCP) atomic arrangement\u0026nbsp;(Fig. 3e), on which Cd atoms can grow continuously and uniformly in a layer-by-layer manner, “abababab”, resulting in the densest atomic packing (Fig. 3f).\u0026nbsp;Therefore, this grain growth pattern prevents the formation of new grain boundaries and, consequently, dendrite growth.\u003c/p\u003e\n\u003cp\u003eWe subsequently quantified the charge-transfer kinetics in 1M and 1M6M electrolytes, by measuring the exchange current densities of Cd//Cd symmetric cells (Fig. 3g and Supplementary Fig. 13). Interestingly, the exchange current density in the 1M6M electrolyte is 3-fold higher than that the 1M electrolyte, reaching to 51.7 mA cm\u003csup\u003e−2\u003c/sup\u003e. Moreover,the 1M6M electrolyte exhibited an ultrahigh ionic conductivity of ~550 mS cm\u003csup\u003e−1\u003c/sup\u003e, researching a level comparable to that of H\u003csup\u003e+\u003c/sup\u003e/OH\u003csup\u003e−\u003c/sup\u003e conduction in aqueous medias\u003csup\u003e28\u003c/sup\u003e and significantly superior to that of the 1M electrolyte (Fig. 3h). These results indicated the much faster kinetics of charge transfer and [CdCl\u003csub\u003e4\u003c/sub\u003e]\u003csup\u003e2−\u003c/sup\u003e desolvation to Cd\u003csup\u003e2+\u003c/sup\u003e in 1M6M electrolyte than that of the charge transfer and the desolvation of hydrated Cd\u003csup\u003e2+\u003c/sup\u003e to Cd\u003csup\u003e2+\u003c/sup\u003e in 1M electrolyte (Fig. 3i).\u0026nbsp;Therefore, this obvious difference in kinetics in 1M and 1M6M electrolytes contributed the inherently different Cd plating behaviors, one a kinetics-limited system and one a fast-kinetics system. Specially, the kinetics-limited 1M system could maintain the regular grain growth up to an areal capacity of 3 mAh cm\u003csup\u003e−2\u003c/sup\u003e, but resulted in the dendritic growth at a high areal capacity of 5 mAh cm\u003csup\u003e−2\u003c/sup\u003e (Supplementary Fig. 9). It indicated that the relatively slow kinetics of charge transfer and desolvation cannot keep up with the rapid and continuous depletion of Cd\u003csup\u003e2+\u003c/sup\u003e in the interfacial layer between electrode and electrolyte as the plated areal capacity increases, thereby disrupting the thermodynamic equilibrium necessary for complete Cd grain growth (Fig. 3i).\u003csup\u003e29,30\u003c/sup\u003e Consequently, it became a kinetics-limited Cd growth process, readily inducing the formation of new grain boundaries and subsequent irregular grain growth.\u003csup\u003e30,31\u003c/sup\u003e In contrast, in the 1M6M system, the ultrafast charge transfer and desolvation enabled the Cd growth process to proceed without kinetic limitations, resulting in a controlled and regular grain growth behavior (Fig. 3i). Therefore, it addressed the dendritic issue under deep cycling of battery.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCorrosion-resistant Cd anode\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn addition to being free from dendritic issue, the corrosion-resistant capability of the metal anode is also paramount for long-term energy storage applications.\u003csup\u003e22\u003c/sup\u003e Notably, the highest aging CE has highlighted the high corrosion-resistant capability of ACBs (Fig. 2j). To further deep study this characteristic, we employed 3 M H\u003csub\u003e2\u003c/sub\u003eSO\u003csub\u003e4\u003c/sub\u003e for additional verification (Fig. 4a).\u0026nbsp;Unlike metallic Zn, which underwent rapid chemical corrosion, gas evolution, and eventual complete dissolution in acidic solution, metallic Cd exhibited high resistance to chemical corrosion and retained its intact macro and micro morphologies.\u0026nbsp;However, in a real aqueous environment, the corrosion scenario becomes significantly more complex due to the added factor of electrochemical corrosion.\u003csup\u003e32,33\u003c/sup\u003e We found that since the redox potential of Cd\u003csup\u003e2+\u003c/sup\u003e/Cd is slightly lower than that of the HER, the Cd anode still faces the risk of electrochemical corrosion (Fig. 4b). We subsequently used the symmetric cells to magnify this risk at continuous current fluctuations of 0.5 mA cm\u003csup\u003e−2\u003c/sup\u003e to induce HER, as shown in Fig. 4c.\u003csup\u003e34,35\u003c/sup\u003e Given the markedly lower redox potential of Zn\u003csup\u003e2+\u003c/sup\u003e/Zn couple compared to HER (Fig. 4b), the Zn//Zn symmetric cell consistently experienced corrosion reactions and thus formed the byproduct of Zn\u003csub\u003e4\u003c/sub\u003eSO\u003csub\u003e4\u003c/sub\u003e(OH)\u003csub\u003e6\u003c/sub\u003e·H\u003csub\u003e2\u003c/sub\u003eO (Supplementary Fig. 14), manifesting in cell polarization and eventual failure after only 45 h (Fig. 4c). In contrast, the Cd//Cd symmetric cells exhibited superior corrosion-resistant capability in both 1M and 1M6M electrolytes, as evidenced by their stable and extremely low voltage fluctuations over 229 h (Fig. 4c). However, byproducts were still detected in 1M electrolyte system during amplified corrosion process, in contrast to smooth Cd anode in 1M6M electrolyte, appearing as fine crystalline Cd(OH)Cl particulates adhering to the Cd anode surface (Supplementary Fig. 15) due to the HER of hydrated Cd\u003csup\u003e2+\u003c/sup\u003e to form Cd(OH)Cl and H\u003csub\u003e2\u003c/sub\u003e.\u003c/p\u003e\n\u003cp\u003eConsidering that amorphous or minimal amounts of byproducts may not be detected by XRD, more quantitative analysis using X-ray photoelectron spectroscopy (XPS) revealed the depth-profiled composition throughout the Cd anode surface (Fig. 5d, e). Compared to the Cd anode in 1M, only superficial layers of bare Cd anode and Cd anode in 1M6M contained O 1s signals, which can be deconvoluted into Cd-OH and Cd-O bands (Fig. 5d).\u0026nbsp;We attributed the presence of these signs to slight oxidation by air (Bare Cd and Cd in 1M6M) or very weak electrochemical corrosion (Cd in 1M6M).\u0026nbsp;Therefore, these signs disappeared after Ar\u003csup\u003e+\u003c/sup\u003e sputtering to the depths of 40 nm and 200 nm. However, notable O 1s signals corresponding to Cd-OH and Cd-O bonds were consistently detected on the surface of the Cd anode (1M) from a sputtering depth of 0 nm to 200 nm. Similar results were confirmed by the Cl 2p signals corresponding Cd-Cl bands (Fig. 5i), in which these notable signals were present on the Cd surface (1M) at various depths but only existed in the superficial layer of the Cd surface (1M6M). Consequently, our amplified corrosion experiments and the comprehensive characterizations demonstrated that the Cd anode in the 1M6M electrolyte is highly resistant to corrosion reactions. Given the variations in the local environment from 1M electrolyte to 1M6M electrolyte, we suggested that the replacement of H\u003csub\u003e2\u003c/sub\u003eO molecules by Cl\u003csup\u003e−\u003c/sup\u003e for hydrated Cd\u003csup\u003e2+\u003c/sup\u003e to [CdCl\u003csub\u003e4\u003c/sub\u003e]\u003csup\u003e2−\u003c/sup\u003e significantly weakened the HER, thereby favoring the dominance of Cd\u003csup\u003e2+\u003c/sup\u003e desolvation and subsequent deposition behaviors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eElectrochemical performance of ACBs\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe electrochemical performance of ACBs was assessed using representative and commercial cathode materials, including coordination-type PANI, capacitance-type AC and intercalation-type V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e, paired with the durable Cd anode.\u0026nbsp;Cyclic voltammetry (CV) profiles\u0026nbsp;were first collected to study the electrochemical behaviors of Cd//PANI full cell (Fig. 5a). The cell in the 1M6M electrolyte exhibited the relatively higher response current and reduction potential, indicating faster reaction kinetics and lower overpotential. Corresponding electrochemical impedance spectroscopy (EIS) demonstrated the smaller charge transfer impedance in the cell in 1M6M electrolyte (Supplementary Fig. 16). Furthermore, the rate performance of Cd//PANI full cells in 1M6M electrolyte showed a discharge capacity of 136 mAh g\u003csup\u003e−1\u003c/sup\u003e at a low current density of 1 mA cm\u003csup\u003e−2\u003c/sup\u003e, which is lightly higher than the cell in 1M electrolyte (Fig. 5b, c). However, this performance difference widened as the current density increased. The cell in the 1M6M electrolyte still exhibited an applicable discharge capacity of 75 mAh g\u003csup\u003e−1\u003c/sup\u003e at a high current density of 50 mA cm\u003csup\u003e−2\u003c/sup\u003e, whereas, in the 1M electrolyte, the discharge capacity of cell decreased to 54 mAh g\u003csup\u003e−1\u003c/sup\u003e. This suggested that the full cell in the 1M6M electrolyte exhibited faster charge transfer and reaction kinetics compared to the cell in the 1M electrolyte. This result was further confirmed by the high exchange current of full cell with the 1M6M electrolyte (Supplementary Fig. 17), indicating the capability of ACBs for high-rate performance.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFurthermore, long-term rechargeable capability of Cd//PANI full cells was evaluated at different high rates (denoted 130 mA g\u003csup\u003e−1\u0026nbsp;\u003c/sup\u003eas 1 C rate), as shown in Fig. 5d, e and Supplementary Fig. 18.\u0026nbsp;It should be noted that although high rates are typically used in aqueous batteries to achieve extended cycle life, rechargeability at low rates remains significantly limited yet necessary.\u003csup\u003e27,36\u003c/sup\u003e However, in our work, the full cell demonstrated its excellent low-rate rechargeable capability at 1.12 C, showing a high capacity retention rate of about 80% after 1,000 cycles (Fig. 5d).\u0026nbsp;Furthermore, at a superhigh rate of 50.34 C, the full cell exhibited exceptional rechargeable capability, retaining 83% of its initial capacity after 20,000 cycles (Fig. 5e), which meets the high-power demands of large-scale energy storage applications. On the other hand, the ACBs demonstrated their high compatibility for multi-scenario application, as confirmed by pairing the Cd anode with capacitance-type AC and intercalation-type V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u0026nbsp;\u003c/sub\u003ecathodes. The Cd//AC capacitor showed typical characteristic of electronic double layer capacitors with large response currents at scan rates from 20 to 100 mV s\u003csup\u003e−1\u0026nbsp;\u003c/sup\u003eand performed excellent rechargeability with a capacity retention of about 90% upon 10,000 charging/discharging cycles (Supplementary Fig. 19). Attractively, the ACB with intercalation-type V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e cathode also performed stable cycling with a high discharge capacity of 270 mAh g\u003csup\u003e−1\u0026nbsp;\u003c/sup\u003eafter 100 cycles (Supplementary Fig. 20).\u003c/p\u003e\n\u003cp\u003eFrom an application perspective, the use of a thin Cd anode with high utilization under deep cycling conditions is essential for practical energy storage infrastructures. Here, we further assembled the Cd//PANI full cell with a high-load cathode of 38.22 mg cm\u003csup\u003e−2\u003c/sup\u003e and a low N/P ratio of 1.91 (anode capacity: 9.09 mAh cm\u003csup\u003e−2\u003c/sup\u003e). As shown in Supplementary Fig. 21a, the high-load full battery using 1M electrolyte could only run for 4 cycles before experiencing a sudden internal short circuit. In contrast, a significantly longer lifespan of 800 cycles was achieved in the full cell using 1M6M electrolyte, with a high cumulative areal capacity of 2.57 Ah cm\u003csup\u003e-\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e (Fig. 5f). Additionally, this high-load and low N/P full cell in 1M6M electrolyte, with a 12-hour rest period per cycle, exhibited a low self-discharge rate of only 5.4% after the first charge to 1.1 V, which further decreased to 2.4% after the twentieth charge to 1.1 V (Fig. 5g, h and Supplementary Fig. 21b). This demonstrated its capability for intermittent usage in practical applications.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, beyond the existing but problematic aqueous metal batteries, we developed a more reliable ACB.\u0026nbsp;We disclosed this ACB operating with a low-cost and quasi-neutral CdCl\u003csub\u003e2\u003c/sub\u003e + NH\u003csub\u003e4\u003c/sub\u003eCl electrolyte, where the reconstructed hydrogen bond network and formed [CdCl\u003csub\u003e4\u003c/sub\u003e]\u003csup\u003e2\u003c/sup\u003e\u003csup\u003e-\u003c/sup\u003e confer the fast kinetics to the ACBs. More importantly, the proposed ACBs addressed the two issues commonly found in metallic anode-based batteries: dendritic growth and anode corrosion. Therefore, it enabled the Cd anode perform the convincing CE of 99.93% and aging CE of 99.34% for plating/stripping behaviors at a high AU of 55% (5 mAh cm\u003csup\u003e-2\u003c/sup\u003e). In addition, the proposed ACB exhibited outstanding compatibility with different types of cathode materials, \u003cem\u003ee.g.\u003c/em\u003e, PANI, AC and V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e. On a practical note, we demonstrated that the ACB with a high-load cathode of 38.22 mg cm\u003csup\u003e\u0026ndash;2\u003c/sup\u003e and a low N/P of 1.91 sustained a high rechargeability over 800 cycles and showed a low self-discharge rate. Therefore, the proposed ACB revitalizes the concept of aqueous metal batteries, and the convincing results highlight its potential for commercialization\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research/project is supported by the Ministry of Education, Singapore, under its SUTD Kickstarter Initiative (SKI 2021_04_14).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eProposal of ideas: Y.-f.C, and H.Y.Y. Design of experiments: Y.-f.C., H.B.S and J.J.Y. Performance of experiments: Y.-f.C, and H.B.S. Materials characterizations: Y.-f.C, H.B.S, Q.H, X.-l.L and Y.-f.L. Writing: Y.-f.C, Y.-h.Z, and H.Y.Y. Approval of the final version of the manuscript: all authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eZhu, Z.\u003cem\u003e\u0026nbsp;\u003c/em\u003eet al. Rechargeable batteries for grid scale energy storage. \u003cem\u003eChem. Rev.\u003c/em\u003e\u003cstrong\u003e122\u003c/strong\u003e, 16610\u0026ndash;16751 (2022).\u003c/li\u003e\n \u003cli\u003eGrey, C. P. \u0026amp; Tarascon, J. M. Sustainability and in situ monitoring in battery development. \u003cem\u003eNat. Mater\u003c/em\u003e\u003cem\u003e.\u003c/em\u003e\u003cstrong\u003e16\u003c/strong\u003e, 45\u0026ndash;56 (2017).\u003c/li\u003e\n \u003cli\u003eChoi, J. W. \u0026amp; Aurbach, D. Promise and reality of post-lithium-ion batteries with high energy densities. \u003cem\u003eNat. Rev. 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Commun.\u003c/em\u003e 59, 2437\u0026ndash;2440 (2023).\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003eMaterials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCadmium chloride (CdCl\u003csub\u003e2\u003c/sub\u003e, 99.99%), ammonium chloride (NH\u003csub\u003e4\u003c/sub\u003eCl, 99.99), Zinc sulfate heptahydrate (ZnSO\u003csub\u003e4\u003c/sub\u003e·7H\u003csub\u003e2\u003c/sub\u003eO, 99%), isopropanol (anhydrous, 99.5%), vanadium (V) oxide (V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e, 99.95%), polyaniline (PANI) and sulfuric acid (H\u003csub\u003e2\u003c/sub\u003eSO\u003csub\u003e4\u003c/sub\u003e, 95%~97%) were obtained from Sigma Aldrich. Cd foil (99.9%), Zn foil (99.9%) and polytetrafluoroethylene (PTFE) aqueous dispersion solution were obtained from the supplier of SCI Materials Hub. Activated carbon (AC, YP80F), conductive carbon (Ketjen black; KB), copper foil, titanium (Ti) mesh and graphite were obtained from the Canrd New Energy Technology.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePreparation of electrodes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCd and Zn anodes preparation: metallic anodes were achieved by continuously rolling of commercial Zn and Cd foils through a roll press (MSK-2150-H5) until a mass of about 11 mg cm\u003cstrong\u003e\u003csup\u003e-\u003c/sup\u003e\u003c/strong\u003e\u003csup\u003e2 \u003c/sup\u003efor Zn foil and about19 mg cm\u003cstrong\u003e\u003csup\u003e-\u003c/sup\u003e\u003c/strong\u003e\u003csup\u003e2 \u003c/sup\u003efor Cd foil were attained, which were subsequently cut into circular foils with a diameter of 1 cm for anode usage. V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e cathode preparation: the commercial V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e and graphite with a mass ratio of 8: 2 were filled into the ball-milling jar and their mixture was ball milled at 500 rpm for 480 min. Subsequently, the V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e cathode was prepared by uniformly grinding the ball-milled V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e/graphite mixture, KB and PTFE in a mass ration of 8: 1: 1 in isopropanol solvent. Finally, the material mixture was pressed into Ti mesh and dried in the vacuum oven at 80 °C for 8 h. Preparation of PANI and AC cathodes: the PANI cathode was prepared by uniformly grinding the commercial PANI, KB and PTFE in a mass ration of 7: 2: 1 in isopropanol solvent. Finally, the material mixture was pressed into Ti mesh and dried in the vacuum oven at 80 °C for 8 h. Preparation of AC cathode is similar to PANI cathode, where the difference lies in the mass ration of AC: KB: PTFE is 8: 1: 1. Finally, all the cathodes were cut into circular electrodes with a diameter of 1 cm.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFabrication of the cells.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll cells were assembled using two-electrode Swagelok-type configurations, supported by SCI Materials Hub, where two electrodes (Zn and Zn, Cd and Cd, Zn and Cu, Cd and Cu, Cd and PANI, Cd and V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e, or Cd and AC) were separated by glass fibre (GF/A, Whatman) using electrolytes (2ZS, 1M or 1M6M electrolyte) of about 80 μL.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials characterizations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e1\u003c/sup\u003eH nuclear magnetic resonance (\u003csup\u003e1\u003c/sup\u003eH NMR) and \u003csup\u003e17\u003c/sup\u003eO nuclear magnetic resonance (\u003csup\u003e17\u003c/sup\u003eO NMR) were conducted on a Bruker (\u003cem\u003eAVANCE\u003c/em\u003e \u003cem\u003eIII,\u003c/em\u003e \u003cem\u003eHD\u003c/em\u003e 500 MHz) NMR spectrometer. The NMR spectra were calibrated to an internal capillary tube containing D\u003csub\u003e2\u003c/sub\u003eO within NMR tube. Scanning electron microscopy (SEM, JEOL JSM-7600F) equipment was used to investigate the microstructure. Fourier transform infrared spectroscopy (FTIR) spectra was recorded using a Thermo (Nicolet 6700) system with a resolution of 4 cm\u003cstrong\u003e\u003csup\u003e-\u003c/sup\u003e\u003c/strong\u003e\u003csup\u003e1\u003c/sup\u003e. X-ray diffraction (XRD) patterns were collected on a Bruker D8 Advanced X-ray diffractometer with Cu Kα radiation. X-ray photoelectron spectroscopy (XPS) tests were performed on an XPS instrument (PHI, Model 5600). The Ar\u003csup\u003e+\u003c/sup\u003e sputtering rate was estimated to be about 5 nm min\u003cstrong\u003e\u003csup\u003e-\u003c/sup\u003e\u003c/strong\u003e\u003csup\u003e1\u003c/sup\u003e. The high/low frequency Raman data were carried out by a Raman spectroscopy (Horiba LabRAM HR Evolution) using a laser with a wavelength of 532 nm. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) mode was conducted on JEM-ARM200F NeoARM with a spherical aberration corrector at 200 kV. HAADF-STEM samples were prepared using a focused ion beam (FIB) of FIB-SEM (ZEISS Crossbeam 540). \u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eElectrochemical measurements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll the electrochemical data were obtained from the two-electrode Swagelok-type configurations. Electrochemical impedance spectroscopy (EIS) was performed over a frequency range of 1 MHz to 10 mHz at an AC amplitude of 10 mV. EIS and Cyclic voltammetry (CV) profiles were collected by a Biologic VMP3 system. Charge-discharge with/without aging process tests of the Zn//Zn symmetric cells, Cd//Cd symmetric cells, Zn//Cu cells, Cd//Cu cells, Cd//PANI full cells, Cd//AC full cells, Cd//V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e full cells, and high-load Cd//PANI full cells were carried out using the galvanostatic method on a multichannel Neware instrument. All the detailed electrochemical test conditions, including current density, areal capacity, load mass of electrodes, and N/P ratio, were given in the Manuscript and Supplementary Information.\u003c/p\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":"","lastPublishedDoi":"10.21203/rs.3.rs-4646240/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4646240/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eAqueous metal batteries have the potential to revolutionize the next-generation energy storage infrastructures due to their high energy density, high safety and low cost. However, two major issues of dendrite growth and corrosion reactions in metal anodes have hindered the deployment of this technology. To address these issues, we report an ideal candidate: aqueous cadmium-metal battery (ACB). The metal cadmium (Cd) anode not only shows a high specific capacity (476.5 mAh g\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e-1\u003c/strong\u003e\u003c/sup\u003e\u003cstrong\u003e) but also offers suitable redox potential (-0.4 V versus standard hydrogen electrode). Additionally, we introduce this ACB operating with a low-cost chloride electrolyte composed of CdCl\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e and NH\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003eCl in water. The inclusion of NH\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003eCl reconstructs the hydrogen bond network of aqueous electrolyte and forms\u003c/strong\u003e \u003cstrong\u003etetrachlorocomplex ([CdCl\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e]\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e2-\u003c/strong\u003e\u003c/sup\u003e\u003cstrong\u003e), which facilitate ultrafast reaction kinetics in ACBs and endow dendrite-free/corrosion-resistant capabilities in Cd anodes. Consequently, the tailored electrolyte achieves a convincing Coulombic efficiency (99.93%) for Cd plating/stripping behavior at a high anode utilization of 55.5%, making it suitable for practical applications. More importantly, the ACBs demonstrate outstanding compatibility paired with coordination-type, intercalation-type and capacitance-type cathodes, exhibiting excellent high-/low-rate and long-term rechargeable capabilities. On a practical note, the high-load ACB with a low negative-to-positive capacity ratio of 1.91 delivers an impressive lifespan of 800 cycles. In summary, our work suggests a practical aqueous battery capable of supporting robust energy storage infrastructures.\u003c/strong\u003e\u003c/p\u003e","manuscriptTitle":"Fast-kinetics and high-compatibility aqueous cadmium-metal battery for next-generation energy storage infrastructures","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-07 07:17:54","doi":"10.21203/rs.3.rs-4646240/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":"265d46a8-ea2f-439e-8f08-a4486c2b873a","owner":[],"postedDate":"August 7th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":34693492,"name":"Physical sciences/Chemistry/Electrochemistry/Batteries"},{"id":34693493,"name":"Physical sciences/Energy science and technology/Energy storage"}],"tags":[],"updatedAt":"2025-07-02T07:15:10+00:00","versionOfRecord":{"articleIdentity":"rs-4646240","link":"https://doi.org/10.1038/s41467-025-60740-2","journal":{"identity":"nature-communications","isVorOnly":false,"title":"Nature Communications"},"publishedOn":"2025-07-01 04:00:00","publishedOnDateReadable":"July 1st, 2025"},"versionCreatedAt":"2024-08-07 07:17:54","video":"","vorDoi":"10.1038/s41467-025-60740-2","vorDoiUrl":"https://doi.org/10.1038/s41467-025-60740-2","workflowStages":[]},"version":"v1","identity":"rs-4646240","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4646240","identity":"rs-4646240","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}