CATHODE ACTIVE MATERIAL USED FOR LITHIUM ION SECONDARY BATTERY AND LITHIUM ION SECONDARY BATTERY

The present invention is to provide a cathode active material used for a lithium ion secondary battery which has a large charge-discharge capacity, and excels in charge-discharge cycle properties, output properties and productivity, and, a lithium ion secondary battery using the same. The cathode active material used for a lithium ion secondary battery comprises a lithium transition metal composite oxide represented by the following Formula (1); LiNiCoMnMO, where, in the formula (1), M is at least one metal element other than Li, Ni, Co, and Mn; and a, b, c, d, e, and α satisfy the following conditions: −0.04≤a≤0.04, 0.80≤b