Patent ID: 8907627

Claim:
A balancer circuit for a cell in a rechargeable battery, the balancer circuit comprising: connecting terminals configured to permit connection of the balancer circuit to the cell; a first resistor electrically connected to one of the connecting terminals; a voltage switch in series with the first resistor and electrically connected to another one of the connecting terminals, the voltage switch being operable to shunt a balancing current through the first resistor when a load voltage sensed over the connecting terminals is higher than a threshold voltage, wherein the voltage switch comprises an adjustable voltage reference circuit having a plurality of terminals, the plurality of terminals including a first terminal, a second terminal and a third terminal configured to input a feedback signal, the first resistor is electrically connected between a terminal of the cell and the first terminal of the adjustable voltage reference circuit, and the adjustable voltage reference circuit provides a Zener diode functional element between the first terminal and the second terminal; a second resistor electrically connected between the first terminal and third terminal; and a third resistor electrically connected between the second terminal and the third terminal.