POWER STORAGE DEVICE

A power storage device includes a power storage module, a pair of current collector plates configured to be stacked to interpose the power storage module in a first direction that is vertical, a pair of insulating plates configured to be stacked to interpose the power storage module and the pair of current collector plates in the first direction; and a pair of restraint plates configured to be stacked to interpose the power storage module, the pair of current collector plates, and the pair of insulating plates in the first direction. The power storage module is configured to include an accommodation space that accommodates an electrolytic solution together with a power generation element. A pressure adjustment valve communicating with the accommodation space is provided on a side surface of the power storage module. The insulating plate arranged on a lower side in the first direction with respect to the power storage module is configured to include a main body portion arranged between the current collector plate and the restraint plate, and a liquid receiving portion that is provided on an outer edge portion of the main body portion, is arranged at least at a position corresponding to the pressure adjustment valve when viewed from the first direction, and stores the electrolytic solution discharged from the power storage module. The main body portion and the liquid receiving portion are integrally formed.