Manganese/nickel composite oxide particles and process for producing the manganese nickel composite oxide particles, positive electrode active substance particles for non-aqueous electrolyte secondary batteries and process for producing the positive electrode active substance particles, and non-aqueous electrolyte secondary battery

摘要

The present invention provides a precursor of positive electrode active substance particles for non-aqueous electrolyte secondary batteries which have a high discharge voltage and a high discharge capacity, hardly suffer from side reactions with an electrolyte solution, and are excellent in cycle characteristics, positive electrode active substance particles for non-aqueous electrolyte secondary batteries, and processes for producing these particles, and a non-aqueous electrolyte secondary battery. The present invention relates to positive electrode active substance particles for non-aqueous electrolyte secondary batteries having a spinel structure with a composition represented by the following chemical formula (1), in which the positive electrode active substance particles satisfy the following characteristic (A) and/or characteristic (B) when indexed with Fd−3m in X-ray diffraction thereof: (A) when indexed with Fd−3m in X-ray diffraction of the positive electrode active substance particles, a ratio of I(311) to I(111) [I(311)/I(111)] is in the range of 35 to 43%, and/or (B) when indexed with Fd−3m in X-ray diffraction of the positive electrode active substance particles, a gradient of a straight line determined by a least square method in a graph prepared by plotting sin θ in an abscissa thereof and B cos θ in an ordinate thereof wherein B is a full-width at half maximum with respect to each peak position 2θ (10 to 90°) is in the range of 3.0×10⁻⁴ to 20.0×10⁻⁴; andLi_1+xMn_2−y−zNi_yM_zO₄  Chemical Formula (1)wherein x, y, z fall within the range of −0.05≤x≤0.15, 0.4≤y≤0.6 and 0≤z≤0.20, respectively; and M is at least one element selected from the group consisting of Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W and Bi.