CYLINDRICAL SECONDARY BATTERY OF IMPROVED SAFETY

摘要

PURPOSE: A cylindrical rechargeable battery is provided to effectively discharge high pressure gas inside a battery by comprising a current interruption member having through-holes with relatively large area and to induce immediate short circuits. CONSTITUTION: A cylindrical rechargeable battery houses an electrode assembly produced by the winding of an anode/separating film/cathode and an electrolytic solution inside a cylindrical can. The cap assembly mounted on the open upper part of the cylindrical can comprises: a safety vent formed with a predetermined notch so as to be ruptured by high-pressure gas in the battery; a current-blocking member which is coupled by welding to the lower edge of the safety vent and blocks current when the internal pressure of the battery rises; and a gasket for the current-blocking member surrounding the outer circumferential surface of the current-blocking member, and wherein the current-blocking member comprises two or more through holes for discharging gas, and the through holes are formed with a size such that their overall surface area is from 20 to 50% of the overall surface area of the current-blocking member.