Laser welding method

Abstract

This laser welding method joins a laminated metal foil in which a plurality of copper-based foils are laminated to a tab plate of a copper-based material. The laser welding method comprises: a step for placing one end of the laminated metal foil on the tab plate; a step for irradiating a plurality of tack welding positions on one end of the laminated metal foil with a blue laser beam; and a step for irradiating a welding line on the tab plate along one end of the laminated metal foil with the blue laser beam.