Here is a tried and tested sample circuit of a Li-Ion battery charger that can be used to charge any 3.7V Li-Ion battery using a 5VDC (USB, Solar Panel…) power supply. At the heart of the circuit is ...

This is the circuit of a simple 12 volt battery charger for Lead Acid battery. It gives 12 volt and 5 Amps current for quick charging of the battery. If the battery is partially discharged, full ...

Ralph’s simple battery charger is essentially this simple voltage regulator circuit. He chose the voltage-setting resistors R1 and R2 to give him 2.5 V on the TL431 when the output sees 3.6 V ...

This simple and inexpensive charger ... The battery pack used contained two AA-size 1200-mAh NiCd cells, so the battery should be charged with 120-mA current. In the charging circuit of Figure ...