Patent ID: 7923147

Claim:
A layered lithium-nickel-based compound oxide powder, which is represented by the following formula (I): Li 1+x Ni 1-y-z-p Mn y Co z M p O 2 (1) wherein 0<x≦0.20, 0.1≦y≦0.5, 0.05≦z≦0.5, 0≦0.2, 0.2≦y+z+p≦0.8, and M is at least one metal capable of suppressing the growth of primary particles of said powder; wherein the valency of at least some of said Ni is III and at least some of said Li is substituted into a transition metal site (3b); wherein said powder comprises secondary particles; wherein said secondary particles are agglomerates of primary particles; and wherein the ratio A/B of the median diameter, A, of said secondary particles to the average particle size, B, of said primary particles is within a range of from 10 to 200.