▎ 摘　　要

NOVELTY - Producing cathode active material coated with reduced graphene oxide on the surface, comprises (a) heat-treating the cathode active material under gas atmosphere containing nitrogen, and doping nitrogen on the surface of the cathode active material to generate a nitrogen-doped cathode active material, (b) generating nitrogen-doped cathode active material coated with graphene oxide on a surface by reacting the nitrogen-doped cathode active material with a mixed solution including graphene oxide, and (c) reducing the graphene oxide to reduced graphene oxide by heat-treating the nitrogen-doped cathode active material coated with graphene oxide on surface under a reducing gas atmosphere. USE - The cathode active material is useful in cathode for lithium secondary battery (all claimed). ADVANTAGE - The method can effectively coat reduced graphene oxide on surface of cathode active material by applying graphene oxide on the surface of the cathode active material doped with nitrogen. The cathode active material can be effectively modified with reduced graphene oxide having excellent conductivity.