Li-Ni COMPOSITE OXIDE PARTICLE POWDER AND METHOD FOR MANUFACTURING SAME, AND NONAQUEOUS ELECTROLYTE SECONDARY CELL

The present invention relates to Li-Ni composite oxide particles that exhibit a high initial discharge capacity and are excellent in thermal stability when used as a positive electrode active substance for non-aqueous electrolyte secondary batteries, and a process for producing the Li-Ni composite oxide particles. The Li-Ni composite oxide particles of the present invention have a composition of Li x Ni 1-y-a-b Co y M1 a M2 b O 2 wherein x, y, a and b represent 1.00 ‰¤ x ‰¤ 1.10; 0 < y ‰¤ 0.25; 0 < a ‰¤ 0.25; and 0 ‰¤ b ‰¤ 0.10, respectively; M1 is at least one element selected from the group consisting of Al and Mn; and M2 is at least one element selected from the group consisting of Zr and Mg, in which a product of a metal occupancy (%) of lithium sites of the Li-Ni composite oxide as determined by Rietveld analysis of X-ray diffraction thereof and a crystallite size (nm) of the Li-Ni composite oxide as determined by the Rietveld analysis is not less than 700 and not more than 1400.