Introduction: 3.5V Solar Panel AA Battery Charger
I'm Manuel and this is my first instructable so if you have any questions, don't hesitate to post a comment.
Today I'm going to show how to make a simple aa battery charger using the light of the sun.
Step 1: Materials:
For this project you need:
- A solar garden light (mine was bought in a dollar store)
- A diode with low voltage drop (I suggest 1n914)
- AA battery holder
- Soldering iron
- An obviously rechargeable batteries
Step 2: Solar Panel
Now remove the solar unit from the steak and open the unit by unscrewing the three screws at the bottom.
Inside there is a small circuit (with a transistor,a resistor and a led) and an AAA ni-mh battery.
The panel is at the top and it's easy to remove.
Step 3: Connections
At this point, using a soldering iron, solder the two wires of the panel to the positive and negative wires of the battery case.
WARNING: respect the polarity of the 2 wires otherwise battery will heat up and they can explode.
Step 4: Conclusion:
It takes a lot to charge up the batteries but it's an interesting project about "green energy".
I hope you enjoy this instructable and soon I'll post another project regarding solar energy... so stay connected!
1 year ago
Sorry, but this seems wrong - don't you need some sort of load balancing? What happens when the batteries are fully charged but the solar panel generates more current - there is no overcharge protection so the batteries might burst and cause a fire. Or am I totally wrong here?
Also how does this cuircut deal with the different levels of voltage generated by the cells? Sometimes you might get almost 5v while other times about 2v
2 years ago
Where does the diode come in? The only mention is that you need one.
5 years ago
Good INFORMATION. Really helpful
For more solar panel related information Once VISIT THIS
5 years ago
This is what I have been looking for. I plan to get a weather station soon that takes a few AA batteries. I'd like to run the wires from a solar cell(s) to trickle charge the device so that I can either extend the run time, perhaps indefinitely. Is there anything different I'd have to do?
6 years ago
You can also wire multiple solar cells together to speed up the rate of charging.
Reply 6 years ago
Yes, of course. This is a basic set up and so it can be improved in several ways.
Thanks for your observation!