Patent ID: 7609031

Claim:
A battery pack control module for balancing a plurality of lithium secondary cells or groups of lithium secondary cells connected in series, wherein the battery pack control module comprises: a controller assembly; a disconnect circuit comprising a charge switch and a discharge switch, wherein the disconnect circuit engages the controller assembly and the plurality of lithium secondary cells or groups of lithium secondary cells connected in series; a pack sensing circuit connected to the controller assembly and the plurality of lithium secondary cells or groups of lithium secondary cells connected in series, wherein the pack sensing circuit comprises: a temperature measuring device; a current measuring device; and a cell voltage measuring device; at least one balancing circuit connected between the plurality of lithium secondary cells or groups of lithium secondary cells connected in series and the controller assembly, wherein each balancing circuit comprises: a shunt resistor connected to a bypass switch; a power source for charging the plurality of lithium secondary cells or groups of lithium secondary cells further connected to the controller assembly; a current limiting resistor connected to the power source for limiting current from the plurality of lithium secondary cells or groups of lithium secondary cells connected in series while charging; at least one configuration table containing cell specifications of the lithium secondary cells disposed in configuration memory connected to the controller assembly; a protective diode connected to the plurality of lithium secondary cells or groups of lithium secondary cells connected in series and to the at least one disconnect circuit, and the protective diode prevents excessive voltage from developing across the controller assembly; computer instructions within the controller assembly for instructing the controller assembly to monitor the state of charge for the plurality of lithium secondary cells or groups of lithium secondary cells connected in series; computer instructions within the controller assembly for instructing the controller assembly to control the disconnect circuit in conjunction with control of the balancing circuit and apply voltage from the power source to the charge switch or discharge switch from a lithium secondary cell or groups of lithium secondary cells when a predetermined state of charge has not been reached or is exceeded; and computer instructions within the controller assembly for instructing the controller assembly to measure the state of charge for each lithium secondary cells after each application of voltage and if a predetermined state of charge is reached for each lithium secondary cell actuate at least a partial discharge of one or more lithium secondary cells simultaneously, enabling simultaneous discharge of one or more lithium secondary cells while one or more lithium secondary cells is charging, discharging, quiescent, or is in storage.