Abstract
Supercapacitors are garnering increasing attention due to their rapid charge/discharge cycles, long cycle life, and high-power density. However, their performance is significantly limited by the choice of electrolyte. Ionic liquids (ILs) offer a promising alternative with their wide electrochemical window, high thermal stability, and non-flammability. However, their high viscosity and limited ionic conductivity pose challenges. Flexible polymerized ionic liquids gel polymer electrolytes (PIL-GPEs) emerge as a solution, combining the advantages of both ILs and solid polymer electrolytes (SPEs). PIL-GPEs inherit the high ionic conductivity and wide potential window of ILs, while the polymer matrix provides mechanical stability and prevents leakage. Additionally, their flexibility makes them suitable for next-generation wearable and flexible electronics. This review delves into the recent advancements in PIL-GPEs for supercapacitor applications. It explores the synthesis methods, material properties, and electrochemical performance of various PIL-GPEs. Additionally, challenges and future directions for research are discussed.