A battery charger (10) recharges reusable batteries (B1, B2,... BN) in a manner that prevents overcharging of the same. The charger includes a voltage source and non-dissipative shunt arrangement that can be customized to charge any number of batteries. The charger (10) may be a current limiting power supply that is controlled by the voltage or charge state of the batteries being recharged. The non-dissipative shunt includes a pair of transistors (Q1, Q2; Q3, Q4;... Q2N-3, Q2N-2) for each pair of batteries and an inductor (L1, L2,... LN-1) placed one end between the battery pair and another end between the transistor pair. An oscillator (14, 204), having two phases (ζ1, ζ2) of equal, but opposite phase, is used to control each transistor to apply charge to a given battery during one phase and then to allow the charge to equalize between the battery pair during the second phase. The equalization is continued until both batteries reach a full charge without overcharging any one battery.
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