Patent ID: 7553583

Claim:
A battery pack comprising: at least one battery module connected to battery pack terminals, plural modules, if provided, being connected in desired configuration to achieve a desired voltage and current capability; each battery module comprising at least two energy storage sections connected in parallel across positive and negative module power buses, said battery pack further comprising module monitoring and protection circuitry for monitoring one or more of the voltage across, current through, or temperature of the module(s), and for providing an interlock signal that controls disconnection of the module(s) from at least one of a charge source and a load responsive to detection of a module fault, wherein said module monitoring and protection circuitry does not control connection of the individual energy storage sections to the module power buses; each energy storage section comprising: (1) at least four battery cells connected in at least two series-connected strings, each of the corresponding single cells of each string also being connected in parallel to form at least two cell groups, each cell group comprising at least two cells connected in parallel, whereby each cell group thus comprises single cells connected in parallel, (2) at least one device for monitoring the operation of the battery cells in each energy storage section, and for providing a disconnect control signal responsive to the operational state of the cells within the energy storage section, said at least one device being capable of separately monitoring each cell group of single cells connected in parallel, such that the cells of each cell group of single cells connected in parallel are monitored collectively; and (3) a controllable element for permanently disconnecting the entire energy storage section from the module power buses responsive to said disconnect control signal, wherein the only means for disconnecting the energy storage sections from the module power buses are comprised by the energy storage sections; and whereby the remaining energy storage section(s) continue to function to deliver energy upon disconnection of any of the other energy storage sections.