The present disclosure relates to a battery pack having improved assemblability, processability, and productivity, and configured to reduce manufacturing costs and enhance the scalability and durability of a pack case. The battery pack includes: a cell assembly including a plurality of secondary cells and a plurality of cartridges, the cartridges being configured to be stacked on one another and to accommodate the secondary cells while surrounding outer circumferential portions of the secondary cells from outsides of the secondary cells; a lower housing having an empty inner space to accommodate the cell assembly in the inner space, the lower housing being opened on an upper side thereof; a lower end plate including a plate-shaped metallic material and placed in surface contact with a lower surface of the lower housing; and a lower cover placed on a lower portion of the lower end plate to cover the lower end plate, the lower cover being fixedly coupled to the lower housing.