Patent ID: 6356055
Filing Date: 2002-03-12
Classification: H02J

Abstract:
A cell voltage balancer for balancing the voltage of a first cell and the voltage of a second cell, wherein the cell voltage balancer comprises a first input terminal, a second input terminal and a third input terminal and the voltage of the first cell is higher than the voltage of the second cell, wherein the cell voltage balancer comprises:a transformer, comprising a primary winding and a secondary winding; a first switch and a second switch, wherein the first switch and the primary winding are serially connected between the first input terminal and the second input terminal and the second switch and the secondary winding are serially connected between the second input terminal and the third input terminal and wherein the first switch and the second switch are turned on and off alternatively; and a first diode and a second diode, wherein the first diode and the first switch are connected in parallel and the second diode and the second switch are connected in parallel; wherein, while the first switch is turned on and the second switch is turned off, the primary winding stores energy from the first cell in the transformer and while the first switch is turned off and the second switch is turned on, the secondary winding recovers energy stored in the transformer and transfers it into the second cell.