| 摘要 |
PROBLEM TO BE SOLVED: To provide a rectangular nonaqueous electrolyte solution battery with a superior safety. SOLUTION: On a battery cap 8, a circular safety valve 9, a thin film of stainless foil, is welded to the side of positive electrode terminal 1 and to the side of negative electrode terminal 2, respectively, wherein the film of safety valve 9 on the negative electrode side is thinner than that on the positive electrode side 1. Beneath each safety valve 9, a lengthwise-shaped, block prevention member 10 is fixed to the back of the battery cap 8, the block prevention member being fixed on its both upper end surfaces, and the safety valve 9 is arranged right above the block prevention member 10, and an aluminum plate 3 or a copper plate 4. When the inner pressure of the rectangular battery climbs, cleaving the safety valve 9 and allowing the contents of electrode groups to move up, together with gas, to the safety valves 9, the safety valve 9 on the negative electrode side cleaves first, so that the cleaved part is not blocked. |
