| 摘要 |
PURPOSE:To obtain a square sealed battery in which a decrease in sealing capability caused by distortion is eliminated by making the inside corner radius of the opening of a case constant before and after the sealing of the battery. CONSTITUTION:A cover plate 3 is arranged inside a gasket 2, and they are inserted into the opening of a metal case 1. The opening end of the case is bent inward with a crimping die and the opening is narrowed so as to have the same dimension as the body to complete a square sealed battery. By making the corner radius of the crimping die equal to the corner radius RC of the case 1 which is nor yet sealed, the straight part of the case 1 is narrowed without deformation of the corner radius, and the distortion caused by crimping is distributed in the straight part. Thereby, the distortion in the crimped part of the metal case is practically removed and steady compression force is applied to the sealing part. |
