A battery module includes a first unit cell, a second unit cell, a first exhaust chamber, and a second exhaust chamber. The first unit cell is disposed so that a positive electrode terminal faces the first direction. The second unit cell is connected in series to the first unit cell, the negative electrode terminal is disposed so as to face the first direction, and the second unit is disposed so as to be adjacent to the first unit cell. The first exhaust chamber is disposed so as to face the positive electrode terminal of the first unit cell, and discharges a gas which is emitted from the positive electrode terminal of the first unit cell. The second exhaust chamber is disposed so as to face the positive electrode terminal of the second unit cell, and discharges a gas generated from the positive electrode terminal of the second unit cell. The end surface of the second unit cell in the first direction and the outer surface of the first exhaust chamber in the first direction are flush with each other. The end surface of the first unit cell in a second direction opposite to the first direction and the outer surface of the second exhaust chamber in the second direction are flush with each other.