Battery pack

The invention is directed to a battery module (100, 300) comprising a plurality of unit battery cells (110, 310) stacked along a first direction (X). An elastic frame (160, 160a, 260, 360) is provided below the plurality of unit battery cells (110, 310), wherein the elastic frame (160, 160a, 260, 360) extends along the first direction (X) and is elastically biased in a second direction (Z) different from the first direction (X).