Molecular Regulation and Intermolecular Chemistry in Gel Polymer Electrolytes for High-Voltage Lithium Batteries

Gel polymer electrolyte (GPE) has garnered widespread attention in the field of lithium batteries because of its low interfacial impedance, high thermal stability, and flexibility. However, the high-voltage compatibility and Li⁺ transport kinetics of GPE have yet to meet the requirements of future high-energy secondary battery systems. In this regard, a comprehensive and insightful review of high-voltage lithium batteries with GPE has attracted significant attention, focusing on molecular design and intermolecular interactions. Molecular regulation involves customizing the polymer matrix, solvent, additive, and Li salt, while intermolecular interactions encompass hydrogen bond interactions, Lewis acid-base interactions, electrostatic interactions, and π-π stacking interactions. Besides, strategies to enhance the stability of the cathode electrolyte interphase and Li⁺ transport kinetics are summarized. It is hoped that this review will provide a deeper understanding of the direct regulation of GPE at the molecular level, further accelerating the commercialization of GPE in high-energy secondary lithium batteries.