US Patent 10177701 Cordless power tool system

A power tool system including a multi-voltage battery pack for use with a first power tool, wherein the first power tool comprises a first battery pack interface and is configured to operate at a first operating voltage and a second power tool configured for use with the multi-voltage battery pack such that the system includes both the multi-voltage battery pack and the second power tool, wherein the second power tool comprises a second battery pack interface and is configured to operate at a second operating voltage, wherein the second operating voltage is higher than the first operating voltage.