BATTERY CELL AND METHOD OF MANUFACTURING THE SAME

A battery cell includes an accommodation portion accommodating an electrode assembly; and a sealed portion extending from a side surface of the accommodation portion externally, and being folded a plurality of times and fixed to be included within a thickness range of the accommodation portion, wherein the sealed portion includes a folded portion disposed to oppose the side surface of the accommodation portion and having a width narrower than the thickness range of the accommodation portion; and a connection portion connecting a center of the folded portion and the accommodation portion, wherein the folded portion includes at least one bent portion formed by folding the sealed portion by 180°.