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Troubshooting my Solar cell phone charger, why doesnt it work? Answered

I recently wired up a solar charger and I have having issues with it not charging my device.  My setup consists of two(2) 5V 100mA solar panels wired parrallel to bump my amperage up to 200mA conected to a 5V step-up USB charching circuit.  I have been able to read 5V coming out of the panels and between 200-300mA but when I plug my phone into the USB cable, i get nothing.  Am I missing something?  Is there a minimum amperage I need in order to charge my phone?  It is an android, motorolla btw.  Here is the power converter that i am using. http://www.amazon.com/DROK-Power-Converter-Module-Charge/dp/B00C93Z8JY.  Please help!


Josehf Murchison

4 years ago

Your solar cells look like 5 volt 200 to 300 ma cells.

The power converter may need more than you are supplying as well as the battery needs.

What is the mah (mill amp hours) of your battery?

You need 600 ma for a 1200 mah battery or 1/2 the mill amp hours in millamps minimum to charge the battery.

Be careful your battery may be marked in watt hours (wh or wvh) divide the watt hours by the voltage marked on the battery and you will get the amp hours.

So if the power converter needs more and the battery needs more than 200 to 300 you need more solar panels.

Also I do not see diodes on your positive or negative of your solar cells, If you do not have diodes on your solar cells one cell can drain the other cutting your current.



4 years ago

While you may measure 200mA from the panels without a load. When you put a load on them they offer only micro amps.

The step up USB circuit you got isn't helping you at all. It's designed to take a lower voltage and step it up to 5V. To do this it has to sacrifice current. The panels already put out vary little current to start with and they probably drop to about 3V when they have a load on them. There just isn't enough current being supplied by the panels to allow the booster to do it's thing. This is why it's best to have the panel trickle charge a battery then use a battery to run charge the device. Like any solar charger it takes days for the panels to charge up any battery. Unless of course it's a fairly large and not vary portable panel.