A battery module includes a plurality of battery cells each having a safety mechanism, a cell case having a plurality of battery housing parts for housing the plurality of battery cells respectively in a predetermined arrangement, an insulating member disposed on one side of each of the battery cells, and a duct serving as a route for exhausting exhaust gas discharged from the battery cells. The battery housing parts have a plurality of openings for housing the battery cells. The insulating member has a through hole formed at a position facing an opening of the plurality of openings that houses corresponding one of the battery cells, and a lid part for closing an opening of the plurality of openings that houses no battery cell. The exhaust gas is discharged to the route of the duct through the through hole of the insulating member.