Abstract : A rugged, level-3 smart battery charger was developed and delivered to the Army. This compact, lightweight charger weighs 22.5 ounces and has a volume of 55 cubic inches. The charger accepts either a universal AC input or a 19-28 VDC input and charges at up to 18 V and 5 A. A daisy-chain capability is included, allowing up to 10 units to be connected to a single power outlet. The operating temperature range is -20 deg C to +55 deg C. Test units passed specified environmental tests including: altitude, humidity, thermal shock, vibration, loose cargo, and drop. Status and error indicators provide visual operating information, and a black-out feature provides on-off control of the indicators.