NOVELTY - Compact fast battery charger consists of voltage controlled circuit which charges battery with variable duty cycle, such that maximum duty cycle during beginning of charging, smaller duty cycle for taper charging and minimum duty cycle for trickle charging at end of charging on battery are maintained. A light-emitting diode indicates rate of charging of battery in response to control signal.    USE - For fast charging of sealed nickel-cadmium (Ni-CAD) and nickel-metal hydride (Ni-MH) batteries and lead acid car batteries, vented nickel-cadmium batteries for industrial application.    ADVANTAGE - Quickly and efficiently charges sealed nickel-cadmium and nickel-metal hydride batteries and other batteries having similar charging characteristics, economical and easy to implement and manufacture, compact.    DETAILED DESCRIPTION - A current source upon control of a control signal turns ON/OFF current supply of a battery which contains two cells connected in series. A voltage controlled circuit senses the voltage across battery and controls control signal. When the voltage controlled circuit senses the voltage across battery reaches a high set point, controls current source to stop current supply by controlling the control signal. When the voltage across battery reaches the low set point, the voltage controlled circuit controls the current source to restore current supply to battery, thereby performing iterative cycles of charging until the high voltage set point of the battery is reached. The voltage controlled circuit continuously repeat the cycle, so that the battery reaches a sustained voltage of low voltage set point. The voltage controlled battery charges battery with variable duty cycle such that maximum duty cycle during beginning of charging, smaller duty cycle for taper charging and minimum duty cycle for trickle charging at the end. A light-emitting diode (LED) indicates the rate of charging in battery in response to control signal.    DESCRIPTION OF DRAWING(S) - The figure shows the schematic diagram of discrete electrical components which make-up the voltage control section of compact fast battery charger.