A battery pack includes a plurality of unit cells, each including a cylindrical battery case, and a connecting member (12) that connects the unit cells to each other. The battery case of each unit cell includes a bottom surface portion (30b) including a plurality of gas discharging sections (32) that open when an internal pressure of the unit cell reaches a predetermined pressure. The gas discharging sections (32) are separated from each other. The connecting member (12) is joined to a non-opening section (34) of the bottom surface portion (30b), the non-opening section (34) being disposed between the gas discharging sections (32).