Patent ID: 6843811
Filing Date: 2005-01-18
Classification: H01M,Y02E,Y02P,Y10T

Abstract:
1. A method of manufacturing a sealed battery, comprising: an external casing preparing step for preparing an external casing that is made of an aluminum alloy, the external casing with an opening and a rim around the opening, a thickness of the external casing at the rim being no greater than a thickness of the external casing at other parts of the external casing; a closure cap preparing step for preparing a closure cap that is made of the aluminum alloy, the closure cap fitting into the opening, the closure cap being a plate with a rib along an outer edge of the plate; a setting step for setting the closure cap to the external casing, after a generator element has been inserted into the external casing, so that the rib comes into contact with the rim; a welding step for welding the rim and the rib together by radiating an energy beam along a boundary between the rim and the rib, wherein the closure cap is prepared at the closure cap preparing step so as to satisfy equations T2≧(T1/10+40) μm and 50(μm)≧T3≧T1, a thickness of the plate being set as T1(μm), a height of the rib being set as T2 (μm), and a thickness of the rib being set as T3(μm) and as a result, heat stress at a time of welding the aluminum alloy is reduced at the welding step.