Battery Charger using Solar & Electrical Power
Description
Table of Contents:
- Battery Charger using Solar & Electrical Power
- Components
Contributor:
D.Mohankumar This Dual Power Source battery charger can utilize two power sources like Solar energy as well as electrical energy to charge a Lead Acid battery. Its charging is voltage and current controlled and can be used as a portable charger in places where AC is not accessible. It also has an LED indicator to show the full charge state of the battery.
Circuit working
AC charger section uses a 0-14 volt 500 mA step down transformer with 1 amps bridge module for rectification and a capacitor C1 for smoothing. This rectified DC passes through Switch S1 to the Variable voltage regulator IC LM317. Its output voltage can be set using the preset VR1.Output from IC1 passes through diode D3 to the gate of SCR 2P4M. When the gate of SCR gets firing pulse from IC1, it triggers and current flows through its cathode for charging the battery. Red LED indicates the power On status.
An LED indicator is also provided to show the Full charge state of the battery. Transistor T1 is used as a switch to light the Green LED when the battery attains full charge. When the battery voltage is less than 11 volts, Zener ZD remains non conducting to keep T1 off. When the battery attains full charge, no more current passes into it and the voltage through R3 rises which causes the breakdown of Zener and T1 conducts. Green LED then lights to indicate the full charge state of the battery.
A 12 volt 150 mA Solar panel is used to charge the battery using solar energy. In bright sunlight, the solar panel generates voltage and current which passes through switch S2. The charging process is similar to the charging using AC.
To set the charge indicator, connect the circuit to a variable power supply or a fully charged battery to give 13.8 volts. Slowly adjust VR2 till Green LED turns on. Use crocodile clips to connect with the battery.
Comments (7)
What is the part number for
What is the part number for the transformer you used?
The Stepdown transformer used
The Stepdown transformer used in the circuit is 0-14 volt 500 mA transformer. It is easily available in all electronics shops selling components.
good design, but i dont
good design, but i dont understand how 11V zenier will work, i think it should be 4-6V since there is a drop across resistors as will, 11V zenior wont be triggered. if im wrong, please explain how it works..
The circuit uses 11 volt
The circuit uses 11 volt Zener diode. As you know, the Zener diode undergoes break down and conduction when it gets 1-2 volts excess than its rated voltage. During charging, the battery takes current so Zener will not conduct.In the fully charged state, the Lead Acid battery attains 13.8 volts and tubular battery 14.8 volts. Voltage drop across R3 is not so high and zener gets around 12 volts for its breakdown. In all automatic chargers ,11 volt zener is used to stop charging when the battery attains full charge.
I have a few questions could
I have a few questions could you please:
1. On solar charging the LM317 is not used at all, not sure from diag if solar o/p is connected to LM317 input
2. It is not a constant voltage charger
3. Does it have a current limiting component?
4. Not sure how the SCR conduction is determined, LM317 will have a contant voltage output, which is connected to the gate
Could you please
Thanks
is it possible to update this
is it possible to update this circuit as varrying current charging from 10to 16A to larger battery (100Ah-150Ah)
D1 serves no purpose. VR2
D1 serves no purpose. VR2 never reaches 11v so the circuit will not work. None of D.Mohankumar circuits works. Do not build anything he produces.
D.Mohankumar always gives the wrong answer, so don't believe what he says. He is wrong.
Colin Mitchell
TALKING ELECTRONICS