Abstract: In one embodiment, the rechargeable, auxiliary battery pack includes a housing made of insulative material that defines an enclosed space and has a top surface cavity which companionately seats a bottom region of a cellular telephone. A bracket holds a standard battery of the telephone as a vertical extension from one end wall of the top surface cavity. A plurality of batteries comprise a battery subassembly that is disposed in the interior of the housing. A four prong female connector is electrically coupled to the battery subassembly and is adapted to mate with a four prong male connector. The male connector is coupled to a 9 volt voltage regulator and beyond the regulator is connected a male plug that is insertable in a car lighter socket such that power from an automobile can be drawn via its lighter to recharge the battery subassembly and enable activation of the cellular telephone. The auxiliary battery pack also includes a female socket that mates with the male plug.