Power storage device and method for manufacturing power storage device

A power storage device comprising:

• a case including a tubular part and a bottom part, the tubular part being cylindrical and including an open end part at one end, the bottom part closing an opposite end of the tubular part;
• a power storage element disposed inside the case, the power storage element including a pair of electrodes;
• a lead connected to one of the pair of electrodes;
• and
• a sealing member sealing the open end part of the case, wherein
• the sealing member includes a gasket including an insulation property and a sealing plate including conductivity,
• the gasket includes a compression part between the tubular part and the sealing plate, and a base that is disk-shaped and is layered with the sealing plate,
• the sealing plate includes a displaceable part and an outer peripheral part surrounding the displaceable part, the displaceable part including a protrusion projecting toward the power storage element, the outer peripheral part being pinched by the compression part,
• the base is disposed between the sealing plate and the power storage element,
• the power storage device further comprises a reinforcing member between the base and the lead, the reinforcing member reinforcing the base,
• the base includes a first through hole,
• the reinforcing member includes a second through hole at a position overlapping with the first through hole,
• the protrusion of the sealing plate is inserted in the first through hole and the second through hole,
• the protrusion of the sealing plate is connected to the lead, and
• the protrusion is disconnected from the lead when displaced in a direction away from the lead in response to an increase in internal pressure of the case.