| 摘要 |
PROBLEM TO BE SOLVED: To achieve further high capacity in a nonaqueous electrolyte secondary battery using a lithium-containing transition metal oxide of a crystal structure belonging to a space group P6mc as a positive electrode active material.SOLUTION: A positive electrode active material used for an exemplary nonaqueous electrolyte secondary battery according to one embodiment of the present invention contains a lithium-containing transition metal oxide having a crystal structure belonging to a space group P6mc as a main component. The lithium-containing transition metal oxide contains at least Co and Ni, and the composition ratio of Co and Ni satisfies CoαNi&bgr;(0.9≤α1<1.0, 0<&bgr;1<0.1). |
