Non-aqueous electrolyte lithium composite oxide for a secondary battery

PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery excellent in charge discharger characteristics, safety, cycle characteristics, and output characteristics. SOLUTION: A lithium composite oxide for a nonaqueous electrolyte secondary battery is represented by general formula Li x Ni (1-y-z-a) Co y Mn z MaO 2 (M represents at least one element selected from the group comprising V, Cr, Ti, Mg, Al, Ca, Nb and Zr; and 1.0≤x≤1.10; 0.4≤y+z≤0.7; 0.2≤z≤0.5; and 0≤a≤0.02), and in a particle size distribution curve of the lithium composite oxide, particles have the particle distribution in which an average particle diameter D50 representing the particle diameter of 50% cumulative frequency is 3-15 μm, a minimum particle diameter is 0.5 μm or more, and a maximum particle diameter is 50 μm or less, and in the relation of D10 of 10% cumulative frequency and D90 of 90% cumulative frequency, D10/D50 is 0.60-0.90, and D10/D90 is 0.30-0.70. COPYRIGHT: (C)2008,JPO&INPIT