Patent ID: RE43956

Claim:
A battery load leveling system for an electrically powered system in which a battery is subject to intermittent high current loading, the electrically powered system including a first battery, a second, and a load coupled to the first and second batteries, said battery load leveling system comprising: a passive electrical energy storage device; a unidirectional electrical conducting apparatus coupled to the passive storage device and to the load, and the unidirectional electrical coupling apparatus configured to conduct current only from the passive storage device to the load, and the passive storage device is in parallel with the first and second batteries to the load; and a battery switching circuit that connects the first and second batteries in either a lower voltage parallel arrangement or a higher voltage series arrangement to allow a measurable terminal voltage of a circuit from the first and second batteries to the load to be switched from a first, higher voltage mode back and forth with a second lower voltage mode; and when the battery switching circuit is in the second lower voltage mode, then the terminal voltage of the circuit from the first and second batteries to the load also is less than a measurable voltage of the passive storage device to the load, and the passive storage device responds to the battery switching circuit being in the second lower voltage mode by supplying electrical current to the load; and further comprising a pre-charge circuit configured to charge said passive storage device using an external power source, wherein said external power source comprises a hybrid vehicle engine that charges said passive storage device through an electrical circuit with the drive configured to accept regenerative power from the load.