Solar Cell Phone

Today I worked on my solar cell phone project. The idea is to try and run my cell phone off the grid.

Panel: 10W (34x20cm, 18V, .6A)
Charge Control: 120W solar regulator (10A max, 12-24V, charge monitor)
Storage: 7Ah sealed lead acid battery
Charger: 3 USB outputs (buck converters with USB out.

I put together a smaller system for my friend Steve who is very interested in energy issues. At the moment it’s not working. I’m going to try and take a look at it this week. Here are the specs:

Panel: 2W(34x20cm, 18V)
Storage: 1.2Ah sealed lead acid battery
Charger: 1 USB outputs (buck converters with USB out.
Hand Crank Backup


to “Solar Cell Phone

  • Okay, it’s Saturday around 1pm. The solar panel is bringing in about .37A at about 12.3V. That’s pretty impressive. The USB charger I assembled doesn’t seem to work with my phone (from overnight). I just added a 120V inverter and am charging three batteries at once. That seems to be going well.

  • The three batteries charging is drawing about .8A.

    So we’re loosing charge. We’ll have to see how long it takes to finish charging the three batteries and how much sun is left in the day.

  • It’s 2:40pm and one of the three batteries just finished charging. I added another.

  • 3:40pm, I now have two batteries that are charged from the system. The voltage is around 12 a the battery and 12.07 at the solar panel.

    I just removed the battery from the phone that was plugged in (the newly charged battery). I transferred one of the batteries from the inefficient chargers into the phone.

    I suspect I will get 3 batteries charged and will still have some sunlight left to charge the system.

  • 5:49pm, I now have a third battery charged off the system. Voltage was 12.01V at solar side. There is still a battery on the system, I hope it’s done shortly.

  • 6:12pm, the forth battery is now charged. The voltage at the battery is 11.42V.