Method for manufacturing battery case and method for manufacturing hermetic battery

Abstract

A battery case is formed by drawing a metallic plate thin to form a cylindrical body 10 having a closed end and cutting away part of the cylindrical body 10 at an opening 11 thereof in the direction perpendicular to an axis of the cylindrical body 10. The cutting of the cylindrical body 10 is carried out by moving a second blade 30 arranged outside the cylindrical body 10 relatively toward the axis of the cylindrical body with a first blade kept abutting the inner circumference of the cylindrical body 10. As a result, an inward burr 13 extending in the direction perpendicular to the side face of the cylindrical body 10 is formed on a cut surface 12 of the cylindrical body 10, but the burr 13 is prevented from entering the battery case.

Dependencies are inferred from the claim text.