Polyimide‐Based Single‐Ion Conducting Gel Polymer Electrolytes for Advanced Lithium‐Ion Batteries

ABSTRACT The evolution of lithium‐ion battery (LIB) electrolytes has progressed from liquid electrolytes (LEs) to advanced polyimide‐based single‐ion conducting gel polymer electrolytes (PI‐SIC‐GPEs). Traditional liquid electrolytes are limited by flammability risks and lithium dendrite growth, which drives the development of solid polymer electrolytes (SPEs) to improve safety. However, SPEs suffer from low ionic conductivity, leading to the introduction of gel polymer electrolytes with the incorporation of plasticizers. Among these advanced polymer electrolytes, PI‐SIC‐GPEs represent a significant breakthrough. By covalently immobilizing anions on thermally robust polyimide backbones combined with stable gel networks, PI‐SIC‐GPEs achieve ultra‐high thermal stability (> 300°C), excellent mechanical properties, high ionic conductivity, near‐unity lithium‐ion transference number (tLi + , approaching 1.0), a wide electrochemical window (up to 5.2 V), and effective dendrite suppression, while maintaining performance across extreme temperatures and wide voltage ranges. This study provides a comprehensive review of PI‐SIC‐GPEs as next‐generation electrolytes for LIBs, detailing design strategies, synthesis methods, interfacial stability, and performance advantages. Challenges regarding scalable fabrication, interfacial compatibility, and plasticizer retention are also addressed. By overcoming these obstacles, PI‐SIC‐GPEs emerge as a promising solution for developing safer, more durable, and higher‐energy‐density batteries, paving the way for future energy storage technologies.