▎ 摘　　要

NOVELTY - The preparation method of cobalt-nickel sulfide/graphene composite material involves mixing cobalt (II) nitrate hexahydrate, nickel(II) nitrate hexahydrate and thioacetamide in ethanol, adding ethanol solution of graphene oxide, ultrasonically dispersing to uniform, transferring to a hydrothermal reactor, performing solvothermal reaction, filtering after the reaction is completed, washing, and drying. USE - Preparation method of cobalt-nickel sulfide/graphene composite material (claimed) for supercapacitor. ADVANTAGE - The method enables environmentally-friendly preparation of cobalt-nickel sulfide/graphene composite material with excellent circulation stability, capacity conservation rate of 87.4% after 5000 cycles, highest energy density of 39.56 W/h.kg-1, power density of 374.8 W.kg-1, and specific capacitance ability, and which controls the quality of the graphene.