Patent ID: 7811478

Claim:
A positive-electrode active material powder, which comprises a granular material (A) capable of doping/dedoping lithium ions and a deposit (B) placed on the surface of the material in a granular or layered form (herein, the material (A) and the deposit (B) are not the same), the percentage of [volumetric sum of particles having a particle diameter of 1 μm or less]/[volumetric sum of entire particles] being 5% or less, wherein the positive-electrode active material powder has an average particle diameter of from 2 μm to 20 μm, inclusive, on a volume basis, wherein the granular material (A) is the oxidized mixture of Li, Ni, and M, in which M is at least one element selected from the group consisting of B, Al, Ga, In, Si, Ge, Sn, Mg, Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Fe, Ru, Co, Rh, Ir, Ni, Pd, Cu, Ag, Zn, and Cd, and wherein the deposit (B) is a compound containing at least one element selected from the group consisting of B, Al, Ga, In, Si, Ge, Sn, Mg, Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Fe, Ru, Co, Rh, Ir, Pd, Cu, Ag, Zn, and Cd.