Electricity storage device

A power storage device (10) is provided with: a positive electrode (21) having a positive electrode current collector (21a) and a positive electrode active material layer (21b); a negative electrode (22) having a negative electrode current collector (22a) and a negative electrode active material layer (22b); a separator (23) disposed between the positive electrode active material layer (21b) and the negative electrode active material layer (22b); and a sealing part (24) that forms a sealed space (S) that accommodates a liquid electrolyte between the positive electrode (21) and the negative electrode (22). One of the positive electrode current collector (21a) and the negative electrode current collector (22a) is an aluminum foil having a thickness of 1 [mu] m or more and 50 [mu] m or less. The other of the positive electrode current collector (21a) and the negative electrode current collector (22a) is an aluminum foil having a thickness of 1 [mu] m or more and 50 [mu] m or less or a copper foil having a thickn