General description:
The PolySwitch battery protection device is a polymeric positive temperature coefficient (PPTC) resettable fuse that functions as a low-resistance series element between battery cells and pack circuits. When the terminals of a pack are shorted, causing an overcurrent condition, the resistance of the PolySwitch device rapidly increases, reducing the discharge of the battery to a safe and protected level. The PolySwitch devices also protect against excessive cell temperatures that can be caused by faulty or incompatible chargers.