Electricity storage device

An electricity storage device comprising:

• a case;
• an electrode group contained in the case;
• an electrolyte contained in the case;
• and two electrode terminal portions provided in the case,
• wherein the electrode group includes a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode,
• wherein the case includes a closed-bottom container body having an opening and a cover plate that closes the opening of the container body,
• wherein the cover plate has terminal holes for placing the electrode terminal portions,
• wherein each of the electrode terminal portions includes
• a bolt-shaped electrode terminal that has a head portion and a threaded portion extending from the head portion and is inserted into a corresponding one of the terminal holes from an inner side of the case to an outer side of the case,
• a ring-shaped insulating first gasket disposed between the electrode terminal and a circumferential portion of the corresponding one of the terminal holes,
• a nut that fixes the electrode terminal to the cover plate,
• a washer disposed between the nut and the cover plate,
• an insulating second gasket disposed between the washer and the cover plate, and
• an insulating third gasket disposed between the head portion of the electrode terminal and the cover plate,
• wherein each of the first gaskets, the second gaskets, and the third gaskets contains a fluororesin,
• wherein an acrylic sealing agent is disposed between each of the second gaskets and a corresponding one of the washers, between the cover plate and each of the second gaskets, between each of the third gaskets and the head portion of a corresponding one of the electrode terminals, and between the cover plate and each of the third gaskets,
• wherein one of the electrode terminal portions is a positive electrode terminal portion electrically connected to the positive electrode, and
• wherein the other one of the electrode terminal portions is a negative electrode terminal portion spaced apart from the positive electrode terminal portion and electrically connected to the negative electrode.