| abstract |
A positive electrode active material capable of producing a secondary battery having excellent battery characteristics is provided. The manufacturing method of the present invention includes Li x Ni 1-yz Co y M z O 2 (1.00 ≦ x ≦ 1.10, 0 <y ≦ 0.15, 0 <z ≦ 0. 15, 0 <y + z ≦ 0.2, M is at least one metal element selected from Al, Mg, Mn, and Ti) to obtain particles having a composite oxide as a main component And a removal step of removing Li from the particles. When calculating the hysteresis area in the range of 0.5 to 0.9 relative pressure (P / P 0 ) of the nitrogen desorption isotherm for the composite oxide particles, the area before the removal step from the area Aa after the removal step is calculated. The removal process is performed so that the value excluding the area Ab is 10 to 100. [Selection] Figure 1 |