▎ 摘　　要

NOVELTY - Composite cathode active material comprises: a core including a lithium transition metal oxide; and a first shell and a second shell that are disposed on the outer side of the surface of the core, where the first shell includes at least one metal compound (I) or (II), and the second shell includes at least one second metal compound (III) and graphene, and where the second metal compound is disposed in a graphene matrix. USE - The composite cathode active material is used for a cathode for a lithium battery (all claimed). The lithium battery is used in laptops, smartphones, and electric vehicles, used in electric vehicles (EVs) because they have excellent lifespan characteristics and high rate characteristics, used in a hybrid vehicle such as a plug-in hybrid electric vehicle (PHEV), and used in application requiring a large amount of power storage, such as in electric bicycles, and power tools. ADVANTAGE - The cathode active material improves low-temperature and high-temperature cycle characteristics and rapid charging characteristics of the lithium battery, and suppresses side reactions between the composite cathode active material and the electrolyte. The cathode active material is capable of preventing deterioration of battery performance by suppressing side reactions of the composite positive electrode active material. The positive electrode provides improved cycle characteristics and thermal stability. DETAILED DESCRIPTION - Composite cathode active material comprises: a core including a lithium transition metal oxide; and a first shell and a second shell that are disposed on the outer side of the surface of the core, where the first shell includes at least one metal compound of formula XaOb(1) or Xa(OH)b(II), and the second shell includes at least one second metal compound of formula YcOd(III) and graphene, and where the second metal compound is disposed in a graphene matrix. An INDEPENDENT CLAIM is included for a method for manufacturing a composite cathode active material, involving providing a lithium transition metal oxide, providing at least one first metal compound (I) or (II) and at least one second metal compound (III), providing a composite comprising graphene, where the second metal compound is disposed in a graphene matrix, and mechanically milling the lithium transition metal oxide, the first metal compound, and the composite. a=0-3; b=0-4 (if a is 1, 2, or 3, b is an integer); c=0-3; d=0-4 (if c is 1, 2, or 3, d is not an integer);and X and Y=Groups 2 to 13, 15 and 16 metals of the Periodic Table of the Elements.