BATTERY DEVICE

The technical idea of the present disclosure provides a battery device including: a base frame; a first cell assembly provided on a main surface of the base frame and including a plurality of first battery cells stacked in a vertical direction perpendicular to the main surface of the base frame and a first side wall attached to the plurality of first battery cells; and a second cell assembly provided on the main surface of the base frame and including a plurality of second battery cells stacked in the vertical direction, wherein the first side wall includes a venting adjustment part configured to adjust a venting direction of gas discharged from the plurality of second battery cells, and the venting adjustment part includes inclined surfaces provided on a surface of the first side wall facing the plurality of second battery cells and inclined with respect to the vertical direction.