| abstract |
(57) [Summary] Lithium-manganese composite oxide particles having high energy density, high charge / discharge capacity, and excellent cycle characteristics when used as a positive electrode active material of a lithium ion secondary battery. And a method for producing the same. According to one present invention, in the general formula (I) Li x Mn 1- yz M y N z O a ( wherein, M represents at least one element selected from the group consisting of Cr and Al, N is B, Mg, Si, Sc, Ti, V, Fe, Co, Ni, Cu, Zn, Ga, Y, Zr, Nb, Mo, Ru, Sn, Sb, Ce, Pr, N and at least one element selected from the group consisting of d, Hf, Ta and Pb, wherein x, y, z and a are each 0. 8 ≦ x ≦ 1.2, 0 <y ≦ 0.2, 0 ≦ z ≦ 0.2 and 1.8 ≦ It is a number that satisfies a ≦ 2.3. Or a composite oxide having a tetragonal crystal system or a composite oxide having a tetragonal crystal system and an orthorhombic crystal system And a lithium-manganese composite oxide particulate composition having an intensity ratio R defined by I (orthogonal) / I (tetragonal) in X-ray diffraction in the range of 0 to 0.3. Is provided. |