Battery cell having improved reliability of preventing humidity penetration

摘要

Disclosed herein is a battery cell including a battery case, wherein the battery case includes thermally bondable portions thermally bonded to each other to constitute a first sealed portion of the battery cell, a first space for receiving an electrode assembly, and second spaces defined outside the thermally bondable portions, the second spaces constituting the outer edges of the battery case together with the thermally bondable portions, and wherein a metal piece for preventing the penetration of humidity into the first space from the outside is mounted in at least one of the second spaces.