Micro Solar Power Bank.

This project is a solar cell battery recharger taken small scale.

This little device was made from parts from my fodder box. I buy the cheap solar powered toy kits off ebay, mostly for the parts.

I was going through the solar cells and trying out which produced the most power under my desk lamp. This one came from one the cheap solar robot kits. The lithium battery came from an equally old and cheap minicamera that never worked to begin with, so I opened it up and saved the battery.

Another one of these mini batteries is shown next to the one I made.

The layout is basic. After I resoldered wires back onto the battery, I used a tiny piece of foam double stick tape to mount it on the back of the solar cell, making sure to match the terminals on both the battery and the cell. I then soldered a blocking diode onto the plus side of the cell. I then soldered the negative of the battery to the negative of the cell, and soldered the positive of the battery to the other side of the diode. As is visible in the pics. I then soldered a black wire to the negative side, and a red wire to the other side of the diode for power. NOW the cell will be trickle charging the battery. In addition I added an orange and white wire to the positive of the solar cell so I can use either the solar cell as is OR the battery power. The excess wiring I cut off.

To finish this off, I recently received a small bag of thermoplastic pellets. This is a type of white plastic that is hard BUT, put it into boiling water and it turns clear and as malleable as modeling clay. So I used some of this plastic to seal up the back of the solar cell. I molded the soft material over the entire back , and around the wires coming out, then set it aside to cool off. It is now a single piece unit thanks to the plastic.

What I'll use this for I don't know yet... Maybe attach a plug to this and use it for one of my MP4 players. Or whatever comes to mind.