MANUFACTURE OF SEALED BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a method for stably and excellently welding a liquid injection port and a sealing plug. SOLUTION: By fixing a sealing plug 2 from a vertically upper direction, moving a laser irradiating head on a cone circular surface or a pyramid surface inclined at 5 to 30 deg. from the vertically upper direction of the sealing plug 2 and welding the irradiating head, excellent welding without perforated defectives by contact part clearance is performed. By deviating a final irradiating location of laser beam from a sealing portion, excellent welding without welding crack defectives is performed.