ENERGY STORAGE DEVICE

An energy storage device includes an electrode assembly and a housing case housing the electrode assembly. The housing case includes a first main wall having a valve hole, and a vent valve closing the valve hole. The vent valve includes a tubular member, a closure film member provided inside the tubular member, and an engaging member and a support member that are connected to the tubular member. The tubular member extends along a hole surface that defines the valve hole. The engaging member is provided on the outer surface of the first main wall. The support member is provided on the inner surface of the first main wall, and supports the electrode assembly.