| 摘要 |
PROBLEM TO BE SOLVED: To provide a lithium secondary battery having a large discharging capacity and good cycle characteristics and manufacturable at a low cost by making proper the composition and particle structure of lithium nickel composite oxide used as positive electrode active material. SOLUTION: Secondary particles having a mean particle size of 5-30 μm are formed by coagulating the primary particles 1 having a mean particle size of 1-8 μm expressed by the formula Lix-yAyNi1-zMzO2, where A is one or more of alkali metals excluding Li and alkali earth metals, M is one or more of Co, Mn, Cr, Fe, V, and Al, and conditions should be met such that 0<x<=1, 0<=y<=0.2, 0<x-y<=1, x+y<=1, and 0<=z<=0.5, and the obtained lithium-nickel composite oxide in which the percentage of voids in the secondary particles 2 is 30% or less is used as positive electrode active material, and thereby a lithium secondary battery is established. |
