| 摘要 |
PROBLEM TO BE SOLVED: To provide a cylindrical battery with a further improved charging/discharging cycle life while securing safety to a rapid increase of an internal pressure during an abnormal time.SOLUTION: A cylindrical battery comprises: a cylindrical exterior can with a bottom; an electrode body housed in the exterior can; and a lid structure including a lid plate 31 on which a gas vent hole 311 is formed, and a valve body 33 formed of an elastic material and contacting the lid plate 31 to block the gas vent hole 311, and sealing an opening of the exterior can. In the lid structure, a ratio of an area in which the valve body 33 contacts the lid plate 31 is 0.6-0.7 to an opening area of the gas vent hole 311. Hardness and a compression ratio of the valve body 33 are set so that a valve activation pressure for elastically deforming the valve body 33 and opening the gas vent hole 311 when a pressure increasing at 0.05 MPa/min. is applied to the valve body 33 through the gas vent hole 311 becomes 3 MPa or more. |
