Patent attributes
A battery pack for use to provide starting power of an internal combustion engine. The battery pack includes an outer housing that encloses a plurality of individual battery cells organized into two battery groups. A charging circuit is contained within the outer housing, which allows the battery cells to be recharged without the need for a charging device other than the battery pack. The charging circuit allows the battery cells to be recharged from either a wall outlet or from the alternator of the internal combustion engine. The battery pack further includes a switching circuit that can configure the battery groups in either a parallel mode or a series mode. In the series mode, the output voltage of the battery pack is increased for starting a cold engine. In the parallel mode, the amount of current available from the battery pack is increased.