Electrochemical Performance of a Potassium‐Ion Complex Gel Electrolyte with Succinonitrile Embedded in an In Situ Constructed 3D Polymer Framework

S cm⁻¹) and transference number (0.72). Furthermore, the 3D polymer matrix confines SN, stabilizing the interface between SN@PPE-2 and potassium metal. When applied in PIBs, SN@PPE-2 demonstrates a capacity retention of 62% over 350 cycles at 50 mA g⁻¹, attributed to the rigid framework's ability to suppress cathode structural deformation, minimize parasitic reactions, and enhance rate performance. This gel electrolyte combines facile synthesis, cost-effectiveness, and scalability, underscoring its potential for industrial implementation.