Rain or Shine Solar Charger

Step 18 Testint, testing, 1,2,3

You're done building! Now, its time to test. Measure the voltage of the pair of AAA NiMH batteries you will be using, then insert them into the battery box. Write down the initial voltage. Place the charger somewhere sunny with the solar cells facing the sun. Go have a snack and clean up the mess that you made. Come back in two or three hours, remove the batteries and measure the voltage again. The batteries should have a voltage .1 to .2 volts higher than they had before. If so, then the charger is working to charge its internal battery. If not, check all your connections and wires between the solar panel and the battery box.

Once the internal batteries are charging properly, let them charge in the sun until they reach 1.4 volts each. At this point, its time to test charging your cell phone. Plug the cell phone in, take a deep breath, and hear that reassuring Bloobloobeep that means it started charging. It'll probably show zero bars or one bar of charge - we're still not charging as fast as a wall adapter would, but this is okay.

If the internal batteries are charging from the solar cells, and the cell phone is charging from the internal battery, congratulations! You just made a solar charger! It takes about 10 hours to charge my phone, yours is likely to be similar unless its a smartphone of some sort.

It'd also be a good idea to test the waterproofness in your shower before taking it on a trip, in case you missed any seams, stitches or gaps.