| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a square secondary battery the orientation of the positive electrode side and negative electrode side of which can be confirmed from the can bottom side.SOLUTION: A square secondary battery C1 including a battery can having a rectangular can bottom surface, a battery lid for sealing an opening facing the can bottom surface of the battery can, and a positive electrode external terminal and a negative electrode external terminal provided on the battery lid, is further provided with an insulation layer 13 covering the outer surface of the battery can 1. The insulation layer 13 is provided with a can exposing parts 51, 52 for exposing a part of the can bottom surface 21, and the can exposing parts 51, 52 have an asymmetric shape with reference to a center line C1 orthogonal to the long side of the can bottom surface.</p> |
