Patent ID: 7199556

Claim:
A method for extending power duration for individual lithium ion cells or groups of individual lithium ion cells connected in series, or connected in parallel and then in series, comprising the steps of: a. monitoring and measuring parameters for a plurality of individual lithium ion cells connected in parallel or groups of individual lithium ion cells connected in parallel, wherein the plurality of individual lithium ion cells connected in parallel or groups of individual lithium ions cells connected in parallel are further connected in series, to determine a state of charge for the individual lithium ion cells connected in parallel or the groups of individual lithium ion cells connected in parallel; b. removing at least a portion or a charge from the state of charge for at least one of the individual lithium ion cells connected in parallel or at least one of the groups of lithium ion cells connected in parallel to achieve a balanced state of charge for the plurality of individual lithium ion cells connected in series, or groups of lithium ion cells connected in series, while in a discharge phase, a charge phase, a quiescent phase, and a storage phase further comprising using a digital controller to execute computer instructions comprising the steps of: monitoring and measuring the state of charge for the plurality or individual lithium ion cells or groups of individual lithium ion cells; activating at least one disconnect circuit for safety between the plurality of individual lithium ion cells or groups of individual lithium ion cells; and activating at least one balancing circuit to achieve balance between the plurality of individual lithium ion cells or groups of individual lithium ion cells.