A battery equalization system comprising at least first and second series connected batteries or battery cells and a battery equalization circuit for equalizing charge between said at least first and second series connected batteries or battery cells, each battery or battery cell (102, 104) including a positive end and a negative end, where the positive end of the second battery or battery cell is coupled to the negative end of the first battery or battery cell at a common node, the battery equalization circuit comprising: a resonant circuit having a first terminal connected to the common node and a second terminal, wherein the resonant circuit comprises a resonant inductor, a resonant capacitor connected in series with said resonant inductor and a bypass inductor connected in parallel to said resonant capacitor, a switching circuit comprising first and second switching transistors connected in a half bridge configuration, wherein the first transistor is connected between the positive end of the first battery or battery cell and the second terminal of the resonant circuit and the second transistor is connected between the second terminal of the resonant circuit and the negative end of the second battery or battery cell; and a transistor drive circuit adapted to produce first and second bias signals for turning the first and second switching transistors (130, 132) on and off, respectively, wherein the transistor drive circuit is coupled to the resonant inductor such that the first and second bias signals are a function of a voltage across the resonant inductor; and wherein the switching circuit is adapted to alternately couple the resonant circuit in parallel with the first and second batteries or battery cells (102, 104) such that a DC current component flows between the first and second batteries or battery cells (102, 104) through the resonant circuit as a function of a charge imbalance therebetween. a resonant circuit having a first terminal connected to the common node and a second terminal, wherein the resonant circuit comprises a resonant inductor, a resonant capacitor connected in series with said resonant inductor and a bypass inductor connected in parallel to said resonant capacitor, a switching circuit comprising first and second switching transistors connected in a half bridge configuration, wherein the first transistor is connected between the positive end of the first battery or battery cell and the second terminal of the resonant circuit and the second transistor is connected between the second terminal of the resonant circuit and the negative end of the second battery or battery cell; and a transistor drive circuit adapted to produce first and second bias signals for turning the first and second switching transistors (130, 132) on and off, respectively, wherein the transistor drive circuit is coupled to the resonant inductor such that the first and second bias signals are a function of a voltage across the resonant inductor; and wherein the switching circuit is adapted to alternately couple the resonant circuit in parallel with the first and second batteries or battery cells (102, 104) such that a DC current component flows between the first and second batteries or battery cells (102, 104) through the resonant circuit as a function of a charge imbalance therebetween.