Poly(Ethylene Glycol)‐Crosslinked Poly(Vinyl Pyridine)‐based Gel Polymer Electrolytes

A series of poly(ethylene glycol) (PEG)‐crosslinked poly(vinylpyridine)s (PVPs)—with PVP serving as the polymer backbone, and PEG side chain of the PVP as the ionic conductor and crosslinker—were developed as novel gel polymer electrolytes. These PEG‐crosslinked PVPs combined the advantages of the pendant PEG as ionic conductors on the polymer side chains with the thermomechanically stable PVPs, and showed self‐standing film‐forming properties without the use of any support. The composition with a pyridine:PEG weight ratio of 45:1 and an ethylene oxide:LiTFSI weight ratio of 10:1, denoted as PVP (45:1)–[10:1], showed a high ionic conductivity of over 1.34 × 10−5S/cm at 25°C, and 2.94 × 10−4S/cm at 80°C. These properties showed the PEG‐crosslinked PVPs to be promising candidate materials as gel polymer electrolytes for lithium‐ion batteries.