▎ 摘　　要

NOVELTY - A graphene/activated carbon composite material preparation method involves subjecting activated carbon to acid treatment followed by obtaining graphene oxide colloid. The graphene oxide colloid is mixed with acid-treated activated carbon followed by ultrasonically dispersing and performing electrostatic self-assembly technology to form graphene oxide coated activated carbon composite slurry. The slurry is dried to obtain graphene/activated carbon composite powder. The graphene/activated carbon composite powder is placed in reducing atmosphere followed by carrying out heat treatment. USE - Method for preparing graphene-activated carbon composite material that is utilized in electrode sheet for supercapacitor (all claimed). ADVANTAGE - The method enables preparing graphene-activated carbon composite material with high density, high pressure resistant property, high electrode density and high volumetric energy density. DETAILED DESCRIPTION - A graphene/activated carbon composite material preparation method involves subjecting activated carbon to acid treatment, dissolving graphene oxide in solvent and carrying out polymer condensation reaction to obtain graphene oxide colloid with positive charge on its surface. The graphene oxide colloid is mixed with acid-treated activated carbon in a mass ratio of (2-20%):(80-98%) followed by ultrasonically dispersing and performing electrostatic self-assembly technology to form graphene oxide coated activated carbon composite slurry. The slurry is dried to obtain graphene/activated carbon composite powder. The graphene/activated carbon composite powder is placed in reducing atmosphere followed by carrying out heat treatment at 800-1600 degrees C for 2-8 hours. INDEPENDENT CLAIMS are also included for the following: (1) a graphene/activated carbon composite electrode sheet (2) a supercapacitor.