A battery according to one embodiment of the present invention comprises a battery cartridge module which generates electric current, and which is formed by stacking a plurality of battery cartridges, each of which has a plurality of through holes formed by opening one side thereof; pack brackets which support the battery cartridge modules such that the battery cartridge modules are stacked into a layer; and a plurality of long bolts inserted into the respective through holes such that the long bolts penetrate through the respective battery cartridges and fasten the battery cartridge modules to the pack brackets.