Introduction: Build a Solar Phone Charger on the Cheap
I do a lot of running around and I can't always get to a power outlet. so my portable phone charger comes in handy.
Problem is if I can't charge my phone I can't charge the charger either. of course I could always buy a portable solar charger.... but where's the fun in that? Not to mention the fact that they run anywhere from 50-300$.
I already had a 4000ma portable charger that i i picked up for twenty bucks. So this project seriously cost me about 3$ but there are some really great "juice boxes" out there. I like the one from Oneplus. 10000ma for like 20$
For this project you will need...
a portable phone charger
basic soldering skill (which I lack)
Step 1: Gather Your Supplies
Now the higher Miliamp your charger the better. but you can pick up a cheap one from almost any grocery store for a few bucks. I got mine at Dee Dee's one day as my girl and I were headed to Disneyland.
As for the solar cells I picked up a couple of these path lamps from wall-mart. You know the kind that you stab in the ground and they come on when it gets dark. These were under a buck a pop. Each one uses a 2v cell. (added bonus: they also use a decent rechargeable AA battery that comes pretty installed.) In full light I get about 2.5v out of each one.
I also used a little Sugu to secure the cells to the backside of my charger. this stuff is pretty cool. it looks like pipe resin but molds like silly putty. and when it dries forms a pretty sturdy rubber.. (in retrospect one pack wasn't enough. I should have made a mount from low temp plastic and glued that on. but that's a trick for another day.
Step 2: Connecting the Panels
As I said each of the salvaged solar panels produces about 2v but to charge our charger we need at least 5v. So we are going to wire three of these guys in SERIES.
Now you will need to solder this but honestly this isn't replacing the U2 IC on your I6. You just need a solid joint. (point of contact... I know what you were thinking Cheech.)
You want to connect them positive to negative just like Christmas bulbs.
Normally I would replace the wires with red and black but ... .I'm lazy today.
Now before moving on use your multimeter to check the combined voltage of the array. (add as many as you like the amperage will never change) you should be getting at least 6v. I had something like 7.5v in direct sunlight.
Step 3: Add Leads to Your Charger
Next up you want to Crack open your charger ( carefully disassemble, don't Crack it... I'm talking to you Monk)
Inside you will find a battery pack and a charging circuit. (this one has an LED flashlight....which I should replace with a LASER!....um.. ignore that...for now o_O.)
You want to find the female micro usb port. We don't want to destroy the port because we do still want to be able to charge it with the cord. So, on the back side of the port you want to attach some leads (wires) to the pins.
the above diagram will show you which pins to solder to. Remember VCC is positive + (red) and Gnd is negative - (black)
Now this one is trickier because the pins are so small so you will need a steady hand on this. you can see how ugly my joints are (in my defence I was doing this in a car with no flux.)
Step 4: Wrap It Up
Lastly just solder your panel array to your leads and test for continuity.. Your charger will probably be shaped different then mine so clean up and make pretty to taste. You can see that during sunset I am still getting a solid 5v out of the panels.
I am just starting to play around with electronics so I am sure you guys have some stuff to teach me. Let her rip in the comments. As always I'll update as I learn.
already need to add a switch. apparently this charger will not output whilst inputing.
Step 6: UPDATE:
So I recently got around to testing the current on these panels. Each one is putting off about 24 miliamps. And since they are wired in series total output of the array is about 6v @ 24ma
about a 100th of the amperage we need to charge a phone in a reasonable amount of time. though this will charge the battery pack.....eventually. By my calculations in order to charge at a decent rate I would need to build an array of these little cells about 4 ft by 4 ft. consisting of 85 cells......:/ back to the drawing board.