| 摘要 |
PROBLEM TO BE SOLVED: To provide a square-shaped secondary battery.SOLUTION: In a square-shaped secondary battery, a flat-shaped electrode body includes a core-body exposed portion of a wound first electrode, the core-body exposed portion of the wound first electrode includes a small thickness part where core-body exposed portions are bundled, a first part located closer to a sealing plate side than the small thickness part and having a thickness larger than that of the small thickness part, and a second part located closer to a bottom side than the small thickness part and having a thickness larger than that of the small thickness part, a current-collecting member is resistance welded to the core-body exposed portion of a wound first electrode, the current-collecting member includes a plate-like first region disposed on the outer most surface side of the small thickness part and a second region extending from an end part of the sealing plate side of the first region toward the sealing plate side than an end part of the sealing plate in the flat shaped-electrode body, and an insulation film is disposed between the second region and the outer most surface of the core-body exposed portion of a wound first electrode. |
