Patent ID: 8920973
Filing Date: 2014-12-30
Classification: H01M,Y02E

Abstract:
1. A positive electrode active material for nonaqueous electrolyte secondary batteries comprising a coating layer containing at least one of nickel and manganese on a surface of a complex oxide particle containing lithium and cobalt, wherein: a binding energy value obtained by analysis of a surface state by an ESCA surface analysis on the surface of the coating layer is 642.0 eV or more and not more than 642.5 eV in an Mn2p3 peak, and a peak interval of Co—Mn is 137.6 eV or more and not more than 138.0 eV; and the positive electrode active material has an average composition represented by the following general formula (1) wherein M1 represents at least one member selected among elements belonging to the Groups 2 to 15 but other than nickel, manganese and cobalt; and p, q, r, s and y represent values falling within the ranges of 0≦p≦1.5, 0≦q≦1.0, 0≦r≦1.0, 0≦s≦1.0 and −0.10≦y≦0.20, respectively; and wherein the complex oxide particle is subjected to a heat treatment after the coating layer is formed thereon, wherein the heat treatment is performed under an inert atmosphere.