A battery device may include a battery frame, and a battery module disposed on the battery frame. The battery frame may include a base member, a slide base being disposed on an upper surface of the base member and being formed in a rectangular shape defined by a pair of first sides extending in a first direction and a pair of second sides extending in a second direction in a plan view, a plurality of metal springs being mounted on an upper surface of the slide base at intervals along the first direction of the slide base, and being extensible in a vertical direction, and a support plate being connected to upper sides of the plurality of springs and supporting the battery module on an upper surface of the support plate.