▎ 摘　　要

NOVELTY - Graphite oxide is ultrasonically dispersed in water, to obtain suspension of graphene oxide. Cobalt hydroxide is added to suspension and ultrasonically dispersed. Obtained mixture is heated at 450-700 degrees C for 0.5-2 hours in protective gas atmosphere, to obtain tricobalt tetroxide-graphene composite material. USE - Preparation of cobalt oxide-graphene composite material used in lithium ion battery. ADVANTAGE - The method enables preparation of cobalt oxide-graphene composite material which provides lithium ion battery having excellent rate characteristics and cycle characteristics.