摘要 |
<p>A method for producing a square cell by welding a sealing plate to the periphery of the opening of a square case containing a power generating element by a laser beam to seal the square case. A sealing plate (2) is placed on an upper opening of a square case (1). The sealing plate (2) has the same shape as that of the opening. A laser beam (3a to 3d) is applied at a downward angle to the sides (a to d) including the corner (e) of a contact line (4) and is scanned along the contact line (4) to seal the opening of the case with the sealing plate.</p> |