BATTERY DEVICE

The technical idea of the present disclosure provides a battery device including: a cooling frame; and a cell assembly disposed on the cooling frame, wherein the cell assembly includes: a plurality of battery cells; a heat transfer structure including a first heat transfer plate connected to electrode leads of the plurality of battery cells and a second heat transfer plate connected to the cooling frame; and an outer cover connected to the first heat transfer plate, wherein at an interface between the first heat transfer plate and the outer cover, the outer cover is continuously contacted to an outer surface of the first heat transfer plate.