| abstract |
A positive electrode active material for a nonaqueous electrolyte secondary cell, which comprises a lithium composite oxide being represented by the formula (1): LiaNibCocMndMeO2 ---- (1) wherein M represents one or two of W and Mo, and 0.90 ≤ a ≤ 1.15, 0 < b < 0.99, 0 < c ≤ 0.5, 0 < d ≤ 0.5, 0 < c + d ≤ 0.9, 0.01 ≤ e ≤ 0.1 and b + c + d + e = 1, and exhibiting an X-ray diffraction pattern which has a primary diffraction peak assigned to a hexagonal crystal structure and also one or more diffraction peaks ascribed to a complex oxide of Li and W and/or a complex oxide of Li and Mo. The positive electrode active material exhibits an elevated capacity and improved thermal stability in a charged state and can be produced at a lower cost, as compared to a conventional LiCoO2 active material used currently. |