The charger charges quickly and easily on all lead-acid batteries. The charger delivers full current, decreases until the current from the battery to 150 mA. At this time, a lower voltage to complement and support more load. If the battery is fully charged, the circuit stops and lights a LED indicates that the cycle is complete. This very simple circuit uses a transformer, two diodes, a capacitor and an ammeter.To charge a battery just connect the + and – terminals of the circuit at the terminals of the battery.If the battery is not charged, shows the ammeter reading 3.1 amps.If the battery is fully charged the ammeter reads zero or nearly zero, after which the battery must be removed from the
The circuit is a full-wave rectifier with two diodes for rectification. The capacitor is used for smoothing.I think the circuit works fine without the capacitor since the battery itself acts like a capacitor BIG. But if the12V power supply circuit (such as a battery eliminator), the capacitor must be present.Care must be taken to reverse the + and – terminals while connecting to the battery.