| 摘要 |
PROBLEM TO BE SOLVED: To break current surely, and discharge inside gas outward so as to prevent the explosion of an armor can when the internal pressure of a battery rises by providing a protrusion portion having predetermined braking strength on the safety valve side of a sealing plate, and welding and connecting the protrusion portion to the safety valve. SOLUTION: When gas is generated resulting from the disorder of a power generating element 3 so that the internal pressure rises rapidly, the gas passed through the gas purging hole 7a of the sealing plate 7 acts on the inside of the safety valve 9 so as to break the protrusion portion 7b of the sealing plate 7 to break an electric circuit. Further, the safety valve 9 is deformed so as to cleave the safety valve 9. Thereby, the gas is discharged outside via the gas purging hole 8a of a battery lid so that the explosion of a battery is surely prevented. When temperature rises resulting from the disorder of an power generating element 3, the electric resistance of a PTC 14 interposed between the battery lid 8 and the safety valve 9 is increased so as to break current flowing to the battery lid 8. |
