Battery cell, battery cell manufacturing device and battery cell manufacturing method

A method for manufacturing a battery cell, comprising:

• a first pressing process of forming a first notching on the other side of a base material by using a first mold portion pressing one side of the base material and a second mold portion including a first protrusion pressing the other side of the base material and supporting the base material;
• and
• a second pressing process of forming a second notching on the one side of the base material by using a third mold portion including a second protrusion pressing the one side of the base material, and a fourth mold portion including a third protrusion pressing the other side of the base material,
• wherein a first width of the first protrusion is greater than a third width of the third protrusion.

A battery cell comprising:

• an electrode assembly;
• a can in which the electrode assembly is accommodated;
• and
• a cap plate sealing an opening of the can and including a first venting portion formed to be ruptured when a pressure in the can is equal to or greater than a preset value,
• wherein the cap plate includes a first surface, and a second surface opposite to the first surface,
• the first venting portion is located between a first notching formed in the first surface and a second notching formed in the second surface, and
• a maximum width of the first notching is different from a maximum width of the second notching.