| 摘要 |
PROBLEM TO BE SOLVED: To provide a square sealed secondary battery, and its manufacturing method, which secure high battery capacity and restraining swelling of an outer package can, is yet of low cost, and has high appearance quality. SOLUTION: The outer package can 10 is in a recessed state toward inside of the battery by forming of a laser irradiation mark 100a, and an inner face of the package can 10 and an outer face of an electrode body 30 are in a contacted state at the part where the laser irradiation mark 100a is formed. The laser irradiation mark 100a is structured of a recrystallized part 102a formed at a part spread in all directions from the center part of a line width toward the inside of a plate material of the outer package can 10, and a heat-affected zone 101a formed at a circular part in contact with the outside of the recrystallized part, from the viewpoint of metal composition. Out of them, the recrystallized part 102a is a region receiving heating, during the forming step of a concave part 110a, up to temperatures within the range of recrystallization temperature or higher and less than a melting point of an Al-Mn group alloy constituting the outer package can 10. COPYRIGHT: (C)2005,JPO&NCIPI |
