| abstract |
Provided is a positive-electrode active material for a nonaqueous-electrolyte secondary cell in which cycle characteristics and high-temperature storage characteristics are improved without damaging the advantage of high capacity inherent to a lithium-nickel composite oxide. A positive-electrode active material for a nonaqueous-electrolyte secondary cell is manufactured with at least an oxidizing roasting step S12, a mixing step S13, and a firing step S14, the positive-electrode active material containing the lithium-nickel composite oxide represented by general formula (1): Li 1 n + n u Ni 1-x-y-z Co x Mn y Mg z O 2 (where u, x, y, and z in the formula satisfy the conditions 0.015≤u≤0.030, 0.05≤x≤0.20, 0.01≤y≤0.10, 0.01≤z≤0.05, and 0.10≤x+y+z≤0.25), and having a crystallite diameter of 100-130 nm. |