Battery cell and battery module including the same

A battery cell, comprising:

• a battery case having an accommodation portion in which a battery assembly is positioned, and a sealing portion formed by sealing an outer periphery thereof by heat fusion;
• an electrode lead electrically connected to an electrode tab included in the battery assembly, the electrode lead protruding out of the battery case through the sealing portion;
• and
• a lead film positioned adjacent to the sealing portion on at least one of a first side and a second side of the electrode lead,
• wherein the lead film includes a gas discharge portion formed to extend from an inside of the battery case to an outside of the battery case,
• wherein the gas discharge portion is opened on a side disposed inside of the battery case, and
• wherein a first end surface of the gas discharge portion is closed and discharges gas therethrough to an outside of the battery cell while closed.