BATTERY MODULE

A battery module includes: a duct extending in a Y axis direction in which a plurality of battery cells are stacked, to form a flow space; and an attachment-target member to which the duct is attached. The attachment-target member has a first wall portion and a pair of second wall portions each rising from the first wall portion in a Z axis direction. The duct is disposed between the pair of second wall portions. The duct has: a third wall portion facing the first wall portion in the Z axis direction with the flow space being interposed therebetween; and a pair of fourth wall portions extending, in the Z axis direction toward the first wall portion, from both end portions of the third wall portion in the X axis direction, the pair of fourth wall portions respectively facing the pair of second wall portions in the X axis direction.