▎ 摘　　要

NOVELTY - Preparing solid electrolyte by in situ self-polymerization of isocyanate comprises (a) mixing isocyanate monomer, lithium salt, initiator and solvent to obtain monomer pre-polymerization solution and (b) injecting the monomer pre-polymerization solution obtained in step (a) into the battery for infiltration and polymerizing to obtain a solid electrolyte. USE - The solid electrolyte is useful in solid-state battery. ADVANTAGE - The solid electrolyte has excellent thermal stability, acid and alkali resistance, flame retardant, redox-resistant ability and improves the cycle performance and safety of the battery. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a solid state battery comprising an anode, a cathode, a separator and an in-situ solid-state electrolyte. The in-situ solid-state electrolyte is a solid-state electrolyte prepared by in-situ self-polymerization of isocyanate monomers.