Patent ID: 7981544

Claim:
A positive electrode for a nonaqueous electrolyte secondary battery using a positive electrode active material mixture, the mixture comprising: a positive electrode active material capable of intercalating and deintercalating a lithium ion; a conductive agent; and a binder, the positive electrode active material being produced by coating the surface of particles of cobalt-based lithium composite oxide represented by a general formula: Li a Co 1-s M1 s O 2 (where composition ratios are 0≦a≦1.1, 0.01≦s≦0.05, M1 contains at least one of Mg, Al, Zr, and Ti) with 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≦t≦0.5, u≧0, 0.1≦v≦0.5), 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 being 2≦r 1 /r 2 ≦50, and the average particle diameter r 2 of the lithium nickel cobalt manganese oxide being 0.5 μm≦r 2 ≦20 μm.