| 摘要 |
Provided is a positive electrode active material for a lithium secondary battery, said active material being represented by composition formula (I) wherein, according to a powder X-ray diffraction measurement using CuKα rays, the ratio α/β between the crystallite size α at a peak in the range 2θ=18.7±1° and the crystallite size β at a peak in the range 2θ=44.6±1° is 1-1.75, inclusive. Li [Lix(NiaCobMncMd)1-x]O2 • • • (I) (Herein, 0 ≤ x ≤ 0.2, 0.3 < a < 0.7, 0 < b < 0.4, 0 < c < 0.4, 0 ≤ d < 0.1, a+b+c+d=1, and M is at least one type of metal selected from the group consisting of Fe, Cr, Ti, Mg, Al, and Zr.) |
