METHOD FOR FORMING SAFETY VALVE FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a method for forming a safety valve for a nonaqueous electrolyte secondary battery, and the nonaqueous electrolyte secondary battery where in the formation process of the safety valve is simplified and the formation cost of the safety valve can be reduced and the parts management of the safety valve saves labor. SOLUTION: In a sealing cap 15, after a thin wall part 20 is formed by a machining work or the like at a region where at least a fragile part 22 is to be formed in a safety valve formation region, the fragile part 22 is formed by applying a laser at a predetermined position of the thin wall part 20 formed at a part of the sealing cap 15, and a safety valve 18 having the fragile part 22 is formed.