| 摘要 |
PROBLEM TO BE SOLVED: To achieve a square secondary battery configured to prevent a metal foreign matter from mixing into inside of the battery by spattering when welding a battery can to a cover.SOLUTION: The square secondary battery of the present invention comprises a power storage body, a battery container which stores the power storage body and has an opening, and a cover which blocks the opening of the battery container and is welded to the battery container. The cover has a blocking part opposing to the opening, a protruding part provided closer to an outer peripheral end part of the cover than the blocking part, and a contact part, provided closer to an outer peripheral end part than the protruding part, which contacts the battery container. A side wall of the battery container has a level difference part near the opening side, where the contact part contacts the level difference part and the protruding part is arranged adjacent to the level difference part.SELECTED DRAWING: Figure 8 |
