| 摘要 |
Provided is a positive electrode active substance having high capacity and low irreversible capacity, excellent initial charge-discharge efficiency, and good rate properties. The positive electrode active substance is represented by the general formula: LixNi1-y-zCoyMzO2 (0.98 <= x <= 1.04; 0.25 <= y <= 0.40; 0 <= z <= 0.07; and M is at least one element selected from among Al, Ti, Mn, Ga, Mg and Nb), and comprises a hexagonal lithium nickel compound oxide that has a laminated structure. The lithium occupancy rate of the lithium main layer is 98.7% or higher as obtained by Rietveld analysis of the X-ray diffraction pattern, and the crystallite diameter is 50 to 300 nm as calculated from the peak of a (003) plane in X-ray diffraction. |
