Abstract: A portable power tool adapter device used to power and charge an electronic device. The power tool adapter device may include an adapter housing with mechanical fittings configured to mate with various power tool battery types, a charger board circuit for controlling various functions of the adapter device, a DC-to-DC step down converter and regulator for converting the high voltage from the power tool to a low voltage, specialized battery input connectors for electrically connecting the battery to the charger board circuit, heat vents for dissipating heat generated by the charger board circuit, a regulator feedback circuit for maintaining output voltages at desired levels, and a multi-pin input/output connector for charging the power tool battery and supplying multiple output voltages when connected to an external connector module.