| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery with excellent thermal stability whether it is in a normal charging state or in a continuous charging state. SOLUTION: A positive electrode active material contains lithium containing cobalt double oxide expressed by the general formula LiCoO2 of which, LiCoO2 with big crystal size and the same with small crystal size are mixed. By the above, thermal stability in the normal charging state is improved due to the liCoO2 with big crystal size having excellent thermal stability due to a stable crystal structure. On the other hand, in the continuous charging state, the battery is dysfunctioned and becomes impossible to charge at a shallow charging stage due to the LiCoO2 with small crystal size. As a result, the safety is not lowered even when continuously charged. |
