| abstract |
(57) [Problem] To provide a positive electrode active material for a non-aqueous electrolyte secondary battery excellent in discharge capacity under a high load, and a non-aqueous electrolyte secondary battery using the positive electrode active material. A positive electrode active material for a non-aqueous electrolyte secondary battery, comprising secondary particles formed by aggregating primary particles, The primary particles are substantially lithium cobaltate represented by the general formula LiCoO 2 , and the ratio of the primary particles appearing on the outer surface of the secondary particles is 38% or more of the entire primary particles by number, and The average particle diameter of the particles is 0.4 μm or more and 6 μm m or less. Alternatively, at least a part of adjacent primary particles is joined by sintering, the average particle size of the secondary particles is in a range of 4 μm or more and 15 μm or less, and the secondary particles are spherical or elliptical spherical. Is preferred. |