| 摘要 |
PROBLEM TO BE SOLVED: To provide an initial charging method of lithium ion secondary battery capable of suppressing reduction in the capacity retention rate.SOLUTION: An initial charging method of lithium ion secondary battery starts initial charging while retaining a lithium ion secondary battery 10 from the outside along the lamination direction of an electrode assembly, and performs low rate charging in a charging range from the start of charging before a change in the stage structure appearing at first. After low rate charging, the lithium ion secondary battery 10 thus retained is released, thereafter it is retained again from the outside, and recharged at a higher rate than that in the low rate charging. |
