PROTECTION METHODS, PROTECTION CIRCUITS AND PROTECTIVE DEVICES FOR SECONDARY BATTERIES, A POWER TOOL, CHARGER AND BATTERY PACK ADAPTED TO PROVIDE PROTECTION AGAINST FAULT CONDITIONS IN THE BATTERY PACK

摘要

In a cordless power tool system, protection methods, circuits and devices are provided to protect against fault conditions within a battery pack that is operatively attached to a power tool or charger, so as to prevent internal or external damage to the battery pack or attached tool or charger. The exemplary methods, circuits and devices address fault conditions such as over-charge, over-discharge, over-current, over-temperature, etc.