POWER STORAGE DEVICE

A power storage device includes a plurality of power storage cells. An end surface portion of a case has an aspect ratio of 1.4 or more. At least a part of a first region between a lower end of a sealing part projected image and an upper end of a principal surface region projected image receives a pressure of a first surface pressure. At least a part of a second region between the upper end of the principal surface region projected image and a lower end of the principal surface region projected image receives a pressure of a second surface pressure. The first surface pressure is higher than the second surface pressure and is 1.5 MPa or more and 3.5 MPa or less. A height of at least a part of the first region receiving the pressure of the first surface pressure is 1 mm or more.