BATTERY DEVICE AND METHOD FOR MANUFACTURING BATTERY DEVICE

A battery device is provided with: an exterior body having two outer side walls; at least one battery cell group that is arranged between the two outer side walls of the exterior body and that is composed of a plurality of laminated battery cells; a first temperature-adjusting medium flow path that is provided in at least one of the two outer side walls of the exterior body and in which a temperature-adjusting medium capable of exchanging heat with the battery cells via the outer side wall flows; and a holding mechanism that brings the battery cell group into contact with the outer side wall so that heat can be exchanged and that holds the battery cell group in the exterior body by applying, to the battery cell group in the exterior body, a pressing force in a direction towards the outer side wall having the first temperature-adjusting medium flow path.