Pyrrolidinium‐PEG Ionic Copolyester: Li‐Ion Accelerator in Polymer Network Solid‐State Electrolytes

Abstract Nonflammable lithium‐ion batteries (LIBs) are developed by adapting polymer solid electrolytes, but their insufficient electrochemical performance has not been fully addressed to date. Crosslinked polymer gel electrolytes with minimal organic solvents (hard gels) are proven to be nonflammable electrolytes, but their lithium metal battery performance is not comparable to those of conventional liquid electrolyte‐based systems. Here, a semi‐interpenetrating polymer network (semi‐IPN) ion‐transporting solid film that comprises a UV‐curable crosslinked polymer and tailored linear pyrrolidinium‐polyethylene glycol copolyester ion channels (named PNPEG), is reported. PNPEG can solvate Li+ effectively with the help of carbonate solvents. Molecular dynamics (MD) simulations confirm that Li+ transportation is accelerated due to the weaker interaction between PNPEG and Li+ ions than betwee…