A known storage cell includes a gas discharging section (safety valve) that opens to prevent, for example, rupture of a cell case when an internal pressure of the storage cell increases due to heat generated by internal short circuiting or the like and reaches a predetermined pressure. For example, PTL 1 discloses a metal battery case including a gas discharging section provided on a bottom surface portion of the case. When the internal pressure of the battery reaches a predetermined pressure, a large opening is formed in the bottom surface portion of the metal battery case.
In the case where a plurality of storage cells are connected together to form an electricity storage device (for example, a battery pack), a connecting member is attached to the bottom surface portion of each cell case. In the storage cell of the related art disclosed in PTL 1, a connecting member is welded to the gas discharging section.