Patent ID: 8043387

Claim:
A production method of a positive electrode for a nonaqueous electrolyte secondary battery, the production method comprising: preparing particles of cobalt-based lithium composite oxide represented by a general formula: Li a CO 1-s M1 s O 2 (where 0<a≦1.1, 0.01≦s≦0.05, M1 contains at least one of Mg, Al, Zr, and Ti) in which a different metal element M1 is homogeneously dispersed; preparing particles of lithium nickel cobalt manganese oxide represented by a general formula: Li b Ni t CO u Mn v O 2 (where composition ratios are 0<b≦1.2, 0.1≦t≦0.5, u≧0, 0.1≦v≦0.5) in which Ni, Co and Mn are homogeneously dispersed (with proviso that a ratio r 1 /r 2 of an average particle diameter r 1 of the cobalt-based lithium composite oxide and an average particle diameter r 2 of the lithium nickel cobalt manganese oxide is 2≦r 1 /r 2 ≦50, and the average particle diameter r 2 of the lithium nickel cobalt manganese oxide particle is 0.5 μm≦r 2 ≦20 μm); obtaining a positive electrode active material in which the surface of the cobalt-based lithium composite oxide is coated with the lithium nickel cobalt manganese oxide by dry-mixing the cobalt-based lithium composite oxide and the lithium nickel cobalt manganese oxide by applying a pressure and a shearing force; obtaining a positive electrode mixture by adding a binder and a conductive agent to the positive electrode active material and by wet-mixing the resultant mixture; and applying the positive electrode mixture to a surface of a positive electrode current collector, and drying and compressing the resultant positive electrode current collector.