NOVELTY - Preparation of high-electroconductive graphene material involves preprocessing graphite, preparing graphene oxide solution, preparing graphene colloid by adding graphene oxide solution to solvent containing water and ethanol, adding reducing agent, adjusting pH, reacting and ultrasonically dispersing, preparing graphene composite material by mixing graphene colloid and pyrrole monomer, ultrasonically treating, adjusting pH, and stirring, adding polyethylene powder to the product, drying, mixing the product with acetylene black and binder, and pressing into current collector.    USE - Preparation of high-electroconductive graphene material used as catalyst, supercapacitor electrode material and fuel cell material.    ADVANTAGE - The method enables simple and economical preparation of high-electroconductive graphene material having excellent electrochemical performance by recycling all solvents.    DETAILED DESCRIPTION - Preparation of high-electroconductive graphene material involves preprocessing graphite by adding 50 g graphite to 1000 mL 98% concentrated sulfuric acid at -10 degrees C to 0 degrees C, uniformly stirring, adding 30 g solid sodium nitrate, stirring for 2-3 hours, adding 120 g potassium permanganate, stirring for 8-9 hours, and obtaining viscous substance, preparing graphene oxide solution by pouring viscous substance into 30% hydrogen peroxide in 100 mL ice water, uniformly stirring, ultrasonically dispersing for 90-120 minutes and washing with 5% aqueous hydrochloric acid, preparing graphene colloid by adding graphene oxide solution to solvent containing water and ethanol in mass ratio of 50:1, such that the volume ratio of graphene oxide solution and solvent is 1:100, adding 50% reducing agent, adjusting pH to 8-9 using 40% aqueous ammonia, reacting in oil bath at 95-100 degrees C for 25-28 hours and ultrasonically dispersing for 40-50 minutes, preparing graphene composite material by mixing graphene colloid and pyrrole monomer in mass ratio of 1:120, ultrasonically treating for 45-55 minutes, stirring in ice bath for 20-25 minutes, adjusting pH to 4-5 by dripping mixed solution of hydrochloric acid solution and iron(III) chloride hexahydrate in the resultant product, and stirring for 80-100 minutes, adding polyethylene powder to the resultant product under mechanical stirring at 90-95 degrees C for 40-50 minutes, evaporating solvent, drying in vacuum oven at 95 degrees C for 20-22 hours, mixing the resultant product with acetylene black and binder in mass ratio of 7:2:2, and uniformly pressing into current collector.