POSITIVE ELECTRODE ACTIVE MATERIAL FOR NONAQUEOUS SECONDARY BATTERIES, METHOD FOR PRODUCING SAME, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY USING POSITIVE ELECTRODE ACTIVE MATERIAL

摘要

[Problem] To provide: a positive electrode active material for nonaqueous secondary batteries, which has small particle diameters and uniform particle size distribution and is capable of increasing battery capacity; a method for industrially producing the positive electrode active material for nonaqueous secondary batteries; and a nonaqueous electrolyte secondary battery which uses the positive electrode active material and has excellent electrical characteristics. [Solution] A positive electrode active material for nonaqueous electrolyte secondary batteries, which is characterized by being represented by general formula Li1+uNixCoyMnzO2+a (wherein 0.40 = u < 0.60; when z - x > 0.4, z - x = u, and when z < 0.6, u = z; 0 = x = 0.5; 0 = y = 0.5; 0.5 = z < 0.8; 0 < x + y; x + y + z = 1; z - x < 0.6; and 0.4 = a < 0.6), by having an average particle diameter of 3-7 µm, and by having an index that indicates the spread of the particle size distribution, namely [(d90 - d10)/average particle diameter] of 0.6 or less.