| 摘要 |
PROBLEM TO BE SOLVED: To provide a safety valve which is opened efficiently when it reaches a case internal pressure of a prescribed level and in which a sufficient opening area can be secured when the valve is opened, and a sealed battery having the safety valve. SOLUTION: The safety valve 40 formed at part of the case of the sealed battery includes a breaking groove 50 formed in a prescribed pattern in a thin wall 42. The thin wall is formed in an oblong or vertical long shape with at least part of its periphery 43 being a curved periphery 45 formed in a curve shape, and the breaking groove has a central straight groove 60 which extends in a major axis direction of the thin wall in the central section and a pair of side grooves 70, which are formed at the both sides in major axis direction of the central straight groove and are connected to the major axis direction ends 60A, 60B of the central straight groove. Here, part of the side grooves is formed in a shape of curve along the curved periphery. COPYRIGHT: (C)2011,JPO&INPIT |
