Patent ID: 8692516

Claim:
A battery balancing system comprising: at least one sub-stack, each sub-stack comprising a plurality of cells connected in series; a balancing module for each sub-stack, the balancing module comprising an independent bidirectional balancer for each cell in the sub-stack; a monitor module configured to sense a SOC of each cell in each sub-stack; a microprocessor configured to determine an average SOC of the cells for each sub-stack; and a daisy chained stackable serial port configured to transmit information to each balancing module, wherein each balancing module is configured to: provide an additional charge to any weak cell from its sub-stack during a discharging of the battery, and remove additional charge from any weak cell and provide it to its sub-stack during a charging of the battery; and remove an additional charge from any strong cell and provide it to its sub-stack during the discharging of the battery, and provide an additional charge from the sub-stack to any strong cell during the charging of the battery.