Patent ID: 8021785

Claim:
A process for producing a cathode active material for a non-aqueous electrolyte secondary battery, comprising: preparing an aluminum complex-containing aqueous solution of aluminum and a carbon compound that forms a water-soluble complex with aluminum; impregnating the aluminum carbon compound complex-containing aqueous solution at a pH of from 3 to 12 into a lithium-containing composite oxide particle of formula: Li p N x O 2 wherein N=Ni y M 1-y-z L z , M is at least one element selected from Co and Mn, L is an element selected from alkaline earth metal elements, aluminum and transition metal elements other than Ni, Co and Mn, 0.9≦p≦1.1, 0.9≦x<1.1, 0.2≦y≦0.9, and 0≦z≦0.3, to obtain a moist aluminum carbon compound complex-impregnated particle; mixing and drying the moist aluminum carbon compound complex-impregnated particle, and subjecting the dried aluminum carbon compound complex-impregnated particle to a heat treatment in an oxygen-containing atmosphere to obtain a surface-modified lithium-containing composite oxide particle wherein a layer from the surface of the surface-modified lithium-containing composite oxide particle to a depth of 5 nm comprises aluminum, and an atomic ratio of the aluminum to a total of Ni and the element M in the layer of 5 nm depth from the surface is at least 0.8.