Zhijun Wu, Yifan Wang, Y H Liu, Hongge Pan, Shengnan He, Yong Wu, Yingying Lu
Solid polymer electrolytes (SPEs) are pivotal for the realization of next‐generation flexible and inherently safe energy storage systems. However, their susceptibility to mechanical fatigue and microcrack propagation during prolonged cycling severely limits their lifespan and reliability. Although the integration of self‐healing capabilities into polymer matrices offers a promising solution, conventional self‐healing electrolytes suffer from an intrinsic trade‐off between mechanical robustness, healing efficiency, and ionic conductivity. Ionic liquid (IL)‐based self‐healing polymer electrolytes have emerged as an ideal candidate to fabricate the performance SPEs, owing to the unique synergistic role of ILs, including acting as nonvolatile plasticizers to accelerate polymer segmental motion for rapid healing and enhance ionic conductivity, also as active components that reinforce the proliferation of reversible supramolecular networks. This review presents a comprehensive survey of IL‐based self‐healing polymer electrolytes, beginning with an elucidation of the fundamental self‐healing mechanisms driven by dynamic supramolecular interactions. The discussion systematically traces the structural evolution of these materials, from systems utilizing solvate ILs and deep eutectic solvents to advanced polyIL architectures. By analyzing how specific molecular designs influence both autonomous repair efficiency and electrochemical performance, this work identifies strategies to reconcile the conductivity‐mechanical strength trade‐off and outlines future directions for constructing resilient, high‐performance SPEs.