Battery cell

A battery cell comprising:

• a case body having an open side and at least one cap plate coupled to the case body to close the open side;
• an electrode assembly accommodated within the case;
• and
• a terminal assembly coupled to the at least one cap plate;
• wherein the terminal assembly includes:
• a current collector electrically connected to the electrode assembly and having a through hole formed therein;
• a terminal head positioned opposite the direction in which the cap plate is located relative to the current collector;
• a terminal pin extending from the terminal head toward the cap plate and inserted into the through hole;
• and
• a protrusion extending from the terminal head toward the cap plate, connected to an outer surface of the terminal pin, and contacting the current collector together with at least a portion of the terminal head.