COMPOSITE CATHODE ACTIVE MATERIAL, AND CATHODE AND LITHIUM BATTERY CONTAINING THE MATERIAL

摘要

PURPOSE: A composite positive electrode active material is provided to improve thermal stability and high voltage performance by a material with olivine structure including a coating layer and/or doped nitrogen atom. CONSTITUTION: A composite positive electrode active material has a lamellar structure and comprises one or more of overlithiated metal oxide; a material with an olivine structure; and a nitrogen atom doped in an inorganic material and the material with the olivine structure. The inorganic material includes a nitride of non-transition metal or carbide. The content of the overlithiated metal oxide is 5-95 weight% of the total weight of the composite positive electrode active material. A region doped with the nitrogen atom in the material with the olivine structure is in a crystalline phase.