A 12V lead-acid battery charger circuit is designed to safely recharge 12V batteries commonly used in vehicles, solar systems, and backup power supplies. The circuit efficiently converts 230V AC mains power into a regulated DC voltage using a step-down transformer and a bridge rectifier. Capacitors are added to filter ripples, providing smooth DC for reliable charging. An LED indicator ensures the circuit is operational, making it user-friendly. This simple and cost-effective design is ideal for DIY enthusiasts and practical applications like maintaining automotive or UPS batteries. It ensures proper charging to enhance battery performance and longevity.
Component Requried
S.no
Components
Value
Qty.
1.
Step Down Transformer
14V/3A
1
2.
Bridge Rectifier
–
–
3.
Capacitor
0.01µf, 100µf
1,1
4.
Resistor
1 KΩ
1
5.
LED
–
–
6.
Battery
12V
–
Circuit Diagram
Circuit Explaination
This 12V lead-acid battery charger circuit efficiently converts 230V AC mains power into a stable DC supply to charge the battery. A 14V/3A transformer steps down the high voltage to 14V AC. The bridge rectifier (diode bridge) converts this AC into pulsating DC, while the 100µF capacitor smoothens it to reduce ripples.
A 0.01µF capacitor further filters high-frequency noise. The 1kΩ resistor limits current to the LED indicator, which glows when the circuit is operational. The stabilized DC voltage charges the connected 12V lead-acid battery safely.
This circuit ensures simplicity and reliability, offering the required charging voltage while minimizing voltage fluctuations. The components are chosen to handle up to 3A current, suitable for most 12V batteries. For additional safety or automatic cutoff features, a voltage regulator or charging controller can be integrated. This basic setup is ideal for DIY enthusiasts or small-scale charging applications.
