▎ 摘　　要

NOVELTY - A cathode coating material comprises a graphene oxide surface-modified with a cationic functional group. USE - Coating material used for forming cathode for lithium secondary battery e.g. lithium-sulfur battery (all claimed). Uses include but are not limited to mobile phones, tablets, laptops and camcorders, electric vehicles and hybrid electric vehicles. ADVANTAGE - The coating material provides the lithium secondary battery having excellent performance by preventing dissolution of lithium polysulfide by applying the coating material grafted with the polymer having cationic functional group on the surface of graphene oxide. The lithium secondary battery has excellent discharge capacity and lifespan characteristics. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) manufacture of the cathode coating material, which involves (a) reacting graphene oxide comprising at least one chosen from carboxyl (-COOH) group and hydroxyl (-OH) group on the surface, and a hydrocarbon structural unit having 1-10 carbon atoms containing 0-2 oxygen including a functional group forming bond with the -COOH group or -OH group and a functional group forming a bond with a vinyl group included in the (meth)acrylate compound to prepare a surface-modified graphene oxide, and (b) reacting the surface-modified graphene oxide with a (meth)acrylate structural unit grafted with 2-10C hydrocarbon group including a cationic group; (2) positive electrode, which comprises a positive active material and the positive electrode coating material coated on the surface of the positive electrode active material; and (3) lithium secondary battery, which comprises the positive electrode, a lithium metal negative electrode, an electrolyte interposed between the positive electrode and the negative electrode and a separator.