A battery rack includes: a plurality of frames, the frames being coupled to each other to form an accommodation space, and at least one of the frames comprising a mount; and a plurality of battery trays, each of the battery trays being configured to be arranged in the accommodation space. Each of the battery trays includes: a tray body configured to accommodate a plurality of unit packs; and a tray plate coupled to the tray body. The tray plate includes a connector configured to be coupled to the mount to ground the battery tray to the frames. One of the mount and the connector includes a protrusion, and the other of the mount and the connector includes an accommodation part configured to be complementarily coupled with the protrusion.