Electrolyte Modulators towards Polarization Immune Lithium-Ion Batteries for Sustainable Electric Transportation

Abstract Lithium-ion batteries for electric vehicles (EV) are subject to fast charging, dynamic acceleration, and regenerative braking. However, the polarization arises from these high-rate operations and tends to deteriorate the battery performance and therefore the driving range and lifespan of EVs. Using metal organic frameworks (MOF) as electrolyte modulators (MEM), we report herein a facile strategy for effective mitigation of polarization, where the MEM can confine anions and enrich electrolyte, affording boosted lithium-ion transference number (up to 0.76) and high ionic conductivity (up to 9 mS cm−1). In addition, such MEM could implant itself into electrolyte interface, conferring the interface with low-resistance and ability to suppress concentration polarization. As a result, commercial cells with MEM deliver remarkably enhanced power output, energy efficiency, and lifespan during high rate (2C, > 3000 cycles) as well as dynamic stress tests (tripled cycle life) that mimic realistic operation of EV. This work introduces a readily implementable approach towards optimizing ion transport in electrolyte and developing polarization immune battery for power-intensive applications.