▎ 摘　　要

NOVELTY - Preparing high-stability lithium-sulfur battery cathode material involves dispersing graphene uniformly in dispersion medium to form graphene dispersion; adding acrylonitrile and initiator to graphene dispersion, and performing graft reaction in inert gas environment to obtain mixed solution; adding deionized water to mixed solution to precipitate polyacrylonitrile grafted graphene from system, centrifuging to remove acrylonitrile which is not grafted on surface of graphene, and drying to remove residual solvent and moisture to obtain dry polyacrylonitrile grafted graphene; dissolving polyacrylonitrile grafted graphene in solvent to prepare polyacrylonitrile grafted graphene solution; preparing polyacrylonitrile grafted graphene solution into polyacrylonitrile grafted graphene fiber web, and then drying to remove residual solvent; mixing polyacrylonitrile grafted graphene fiber net with elemental sulfur. USE - Method for preparing high-stability lithium-sulfur battery cathode material. ADVANTAGE - The method enables to prepared lithium-sulfur battery, which has excellent cycle stability and specific capacity. DETAILED DESCRIPTION - Preparing high-stability lithium-sulfur battery cathode material involves dispersing graphene uniformly in dispersion medium to form graphene dispersion; adding acrylonitrile and initiator to graphene dispersion, and performing graft reaction in inert gas environment to obtain mixed solution; adding deionized water to mixed solution to precipitate polyacrylonitrile grafted graphene from system, centrifuging to remove acrylonitrile which is not grafted on surface of graphene, and drying to remove residual solvent and moisture to obtain dry polyacrylonitrile grafted graphene; dissolving polyacrylonitrile grafted graphene in solvent to prepare polyacrylonitrile grafted graphene solution; preparing polyacrylonitrile grafted graphene solution into polyacrylonitrile grafted graphene fiber web, and then drying to remove residual solvent; mixing polyacrylonitrile grafted graphene fiber net with elemental sulfur, conducting semi-carbonization and vulcanization reactions in closed pressure tank in inert gas environment, then opening pressure tank, heating to remove adsorbed sulfur on surface, and drying to remove moisture to obtain semi-carbonized vulcanized polyacrylonitrile grafted graphene fiber web; using semi-carbonized sulfurized polyacrylonitrile grafted graphene fiber mesh directly as lithium-sulfur battery cathode material or semi-carbonized sulfurized polyacrylonitrile grafted graphene fiber mesh which is made into semi-carbonized sulfurized polyacrylonitrile grafted graphene fiber mesh, mixing carbonized sulfurized polyacrylonitrile grafted graphene fiber powder with binder and coated on surface of metal foil as lithium-sulfur battery cathode material.