Patent ID: 6924625

Claim:
A battery pack comprising: a rechargeable battery having a first electrode and a second electrode; and a protection device to protect the rechargeable battery when a rechargeable battery abnormality is detected, wherein the protection device has output terminals including: an externally exposed first output terminal connected to the first electrode of the rechargeable battery, an externally exposed second output terminal connected to the second electrode of the rechargeable battery, an externally exposed third output terminal for signal detection, and a contact switching section allowing contact to be switched to protect the rechargeable battery when a rechargeable battery abnormality is detected, and wherein the protection device is the output terminals and contact switching section formed as a single piece, wherein the contact switching section has a first end connected to the second output terminal, and a second end which is connected to allow switching between a contact connected to the second elcetrode of the rechargeable battery and a contact connected to the third output terminal, wherein when no abnormality is detected the other end is connected to the contact connected to the second electrode of the rechargeable battery, and wherein when an abnormality is detected, the other end switches to the contact connected to the third output terminal.