Battery module

A battery module includes: a plurality of second battery cells, each including an electrode lead connected to an electrode assembly, a terrace portion of a cell body member in which the electrode assembly is accommodated, and a sealing portion connected to the terrace portion; a housing unit in which the plurality of secondary battery cells are accommodated; and a guard unit including a first area, facing at least a portion of the terrace portion, to delay swelling or bursting of the sealing portion of at least one of the plurality of secondary battery cells. The guard unit has a shape in which a first gap is smaller than a thickness of the cell body member to limit expansion of a thickness of the terrace portion, the first gap being a distance between internal surfaces of the first area.