| 摘要 |
There is provided a nonaqueous electrolyte secondary battery which can reliably perform a current cut-off operation in a current cut-off state and can release a gas in a cleavage state. In the safety valve 6, a plurality of linear thin portions are formed along two circles centering on the projecting portion 6a. A thin portion extending in a radial direction is formed across the end portions of the thin portions adjacent to each other. In this manner, by the plurality of thin portions, one continuous thin portion is formed. In a safety valve in which the projecting portion is connected to the lead of the electrode element through the central hole of the disk, the disk has a linear thin portion, or a linear thin portion is formed almost along a circle centering on the symmetrical point of the central hole. |
