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

Provided are a positive electrode active material for nonaqueous secondary batteries, the material having a narrow particle-size distribution and a monodisperse property and being capable of increasing a battery capacity; an industrial production method thereof; and a nonaqueous secondary battery using the positive electrode active material and having excellent electrical characteristics. The positive electrode active material is represented by a general formula: LiNiCoMnMO(wherein, 0.05 ≤ u ≤ 0.95, x + y + z + t = 1, 0 ≤ x ≤ 0.5, 0 ≤ y ≤ 0.5, 0.5 ≤ z < 0.8, 0 ≤ t ≤ 0.1, and M is an additive element and at least one element selected from Mg, Ca, Al, Ti, V, Cr, Zr, Nb, Mo, and W), has an average particle diameter of 3 to 12 um, and has [(d-d) /average particle diameter], an index indicating a scale of particle-size distribution, of 0.60 or less. (150 word)