Patent ID: 8766598

Claim:
A charge equalization apparatus, comprising: multiple transformers, each having a primary winding and a secondary winding wound around the transformer, the primary windings of the transformers being connected in parallel with each other, the secondary windings of the transformers being connected in parallel with battery cells; wherein the primary windings and the secondary windings of the multiple transformers form flyback converters; multiple first current transfer devices connected in series with the secondary windings of the multiple transformers, respectively; multiple battery cells connected in series with each other, and connected in parallel with the secondary windings of the multiple transformers, the battery cells being constructed so that a first end of the multiple series-connected battery cells is connected to first ends of the parallel-connected primary windings of the multiple transformers; a first switch connected to the first ends of the parallel-connected primary windings of the multiple transformers, thus controlling flow of current of the primary windings in a first direction or a second direction; and a voltage sensing and switch drive signal generation unit for sensing voltages of the multiple battery cells and turning on/off the first switch, wherein the charge equalization apparatus is operated such that, when the first switch is turned on, current flows through the primary windings in the first direction, and current is induced in the secondary windings, thus enabling equalized charge to be distributed to the multiple battery cells; and wherein the polarity of the primary winding in the multiple transformers is opposite to the one of the secondary winding; when the first switch is on, the first current transfer devices prevent the current flow and store the magnetic energy on the secondary winding; when the first switch is off, the magnetic energy stored on the secondary winding charges the battery cell so that the charge becomes equalized.