Abstract: A portable, rechargeable device for boost-charging a discharged target battery is equipped with current sensing and regulation circuitry. The device may be used, for example, for boost-charging through a cigarette lighter socket or directly. Such circuitry permits very rapid charging using voltages greater than the nominal voltage of the target battery without blowing a fuse of the cigarette lighter socket or damaging sensitive onboard electronics.

Abstract: A portable electrical energy source includes a portable housing having an outer surface and defining an interior space. A direct current battery is disposed in the interior space. A direct current socket is supported on the housing and electrically coupled to the battery for supplying direct current from the battery to a device outside the housing. An inverter is provided for converting direct current into alternating current and includes an electrical lead have a male plug adapted for being electrically connected to the battery via the direct current socket and an electrical outlet for supplying alternating electrical current to a device outside the housing. The inverter is removably attached to the outer surface of the housing so that the inverter can be ported together with the battery inside the housing and selectively separated from the housing and used independently of the battery in the housing.