| 摘要 |
PURPOSE: Provided are a secondary battery including a safety valve which prevents the battery explosion caused by ascent of an internal pressure in the battery, and a method for manufacturing the safety valve easily and inexpensively without any further process. CONSTITUTION: The secondary battery includes an electrode assembly having a positive electrode plate, a negative electrode plate and a separator disposed therebetween; a can(10) in which the electrode assembly is accommodated; a cap plate which seals an opening part of the can(10); and a safety valve(SV) which is ruptured upon ascent of an internal pressure beyond a standard value, so that the internal pressure can be reduced, wherein the safety valve(SV) is provided in a sealing part(SP) of the cap plate and the can(10). The sealing part(SP) comprises a high sealing part(HSP) and a low sealing part(LSP), and the safety valve(SV) is formed in the low sealing part(LSP). The safety valve is manufactured by controlling the crimping strength of a portion in the sealing part to form the low sealing part having lower crimping strength. |
