Patent ID: 7274170

Claim:
A battery pack control module for balancing a plurality of cells or groups of cells connected in series, wherein the battery pack control module consists of: a. a controller assembly comprising an analog controller and a digital controller; b. a disconnect circuit, comprising a charge switch and a discharge switch connected in series, engaging the controller assembly and the plurality of cells or groups of cells connected in series; c. a pack sensing circuit comprising a member selected from the group consisting of means for measuring battery pack system module temperature, means for measuring battery pack system module current, means for measuring cell voltages, or combinations thereof; wherein the pack sensing circuit connects to the controller assembly and the plurality of cells or groups of cells connected in series; d. a balancing circuit comprising a shunt resistor connected to a by-pass switch, wherein the balancing circuit connects between the plurality of cells or groups of cells connected in series and engages the controller assembly; and e. computer instructions for instructing the controller assembly to control the disconnect circuit and the balancing circuit; and wherein the plurality of cells or groups of cells connected in series are balanced when the battery pack control module operates in a charging phase, a discharging phase, a quiescent phase, and a storage phase.