PURPOSE: To prevent the generation of welding failure without allowing lithium adhere to the opening end of a battery case by making a metal thin plate contact the end of the surface, which faces outside, of a lithium plate the lithium plate is formed into a cylindrical shape, winding said thin plate around a cylindrical body, and inserting it in the battery case.
CONSTITUTION: A cylindrical body 1 is formed by making a metal thin plate 2 contact in a U-shaped form so as to cover both sides of one end of a lithium plate 1a that is cut in specified dimensions, crimping it, and winding the lithium plate 1a in a cylindrical form. The lithium cylindrical body 1 is inserted in a battery case 5 from the side where the metal thin plate 2 is made to contact. In this case, since the lower end of the lithium body 1 and the peripheral surface in its vicinity are covered with the metal thin plate 2, lithium does not adhere to the opening end of the battery case. As a result, the periphery of the metal body section 7 of a cover 6 and the opening end of the battery case 5 are welded together using plasma arc, laser, etc., without generation of welding failure.
IWAMARU FUTAYASU
ISHIKAWA HACHITANI
