Harbor Freight Solar Powered Cell Phone Charger

Harbor Freight Solar Powered Cell Phone Charger.

This 1.5 watt Solar panel from Harbor Freight was $10.86 after I used a % 20 off
coupon. 
It's supposed to trickle charge batteries and keep the batteries current charge 
constant.
So if your battery is at 12.2 volts, it should maintain 12.2 volts.
It does that just fine. 
It's more of a battery maintainer than an actual charger. 
If you're looking for something to charge a dead battery, 
this is probably not going to work for you.
It didn't charge my phone. 
But, it has maintained the full charge on my phone.
Solar power is nifty!

If you don't want to make your own.