Composite cathode active material, cathode and lithium battery including the composite cathode active material, and method of preparing the composite cathode active material

摘要

A composite cathode active material, and a cathode and a lithium battery each including the composite cathode active material. The composite cathode active material includes: a core including a first lithium transition metal oxide represented by Formula 1,Li_aMO₂ wherein, in Formula 1, M includes Ni and at least one non-nickel Group 4 to Group 13 element, a content of Ni is about 70 mol % or greater, based on a total content of M, 0.9≤a≤1.1, and wherein the first lithium transition metal oxide has a layered crystal structure belonging to an R³m space group; and a shell on a surface of the core, the shell having a spinel crystal structure and including a dopant.