HERMETICALLY SEALED BATTERY, BATTERY PACK USING THE HERMETICALLY SEALED BATTERY, AND ELECTRONIC APPARATUS EQUIPPED WITH THE BATTERY PACK

摘要

A hermetically sealed battery including a liquid injection hole provided in a battery case and a seal that blocks the liquid injection hole, the liquid injection hole being sealed with the seal by welding the seal to a portion around the liquid injection hole in a state in which an electrolyte solution is injected into the battery case. The seal is formed of a metal body in which an aluminum layer formed of aluminum or an aluminum alloy and a dissimilar metal layer formed of a metal different from aluminum or an alloy of the metal are joined one on top of the other. A lead that is connected to a PTC element or a protection circuit is joined to the metal body. The joining strength between the lead and the metal body is less than the joining strength between the seal and the portion around the liquid injection hole.