Here is a solar charger circuit that is used to charge Lead Acid or Ni-Cd batteries using the solar energy power. The circuit harvests solar energy to charge a 6 volt 4.5 Ah rechargeable battery for various applications. The charger has Voltage and Current regulation and Over voltage cut off facilities. Solar Charger Circuit Schematic Solar charger with current regulation and cut off. buy the components for this solar charger project Ready-Made Solar Charger – different ready-made solar battery chargers LM317 – 1.2V to 37V linear regulator BC548 – Bipolar Transistor NPN 30V To-92 Lead Acid Battery – 6V 4.5Ah Sealed The circuit uses a 12 volt solar panel and a variable voltage regulator IC LM 317. The solar panel consists of solar cells each rated at 1.2 volts. 12 volt DC is available from the panel to charge the battery. Charging current passes through D1 to the voltage regulator IC LM 317. By adjusting its Adjust pin, output voltage and current can be regulated. VR is placed between ...