DIY Solar Phone Charger ($5 Battery Free - UPDATED!)

Picture of DIY Solar Phone Charger ($5 Battery Free - UPDATED!)
Here's a real quick and easy tutorial on making a "Portable Solar Phone Charger", it only took me 5 minutes to make one! It's powered by PURE solar energy. The device is designed to fit right into your pocket, it also comes with a built-in stand! Works with apple devices (tested on iPod Touch and Quadcore Android Phone)

How Does It Work?
Solar powered chargers and powerbanks are pretty common these days. These devices usually have battery reservoirs inside them, to cut it short they are not 100% solar powered so as being eco-friendly. These products are gimmicks, they defeat the purpose of being 100% green and eco-friendly. My DIY tutorial will teach you how to make a "100% PURE Solar Phone Charger". Feel free to be independent from the power grid :D

My Review: (Pure Solar vs. Solar+Battery) 

  100% Pure Solar: (Pros)                           100% Pure Solar: (Cons)
   - 100% eco-friendly                                     - Can only charge devices during day
   - No need for charging internal bat.             - May Not Work with TABLETS (High Amp. Devices)
   - Independent From The Power Grid          - Ideal for outdoor use (where sunlight is present)
Solar Power Bank (w/battery): (Pros)            Solar Power Bank (w/battery): (Cons)
   - Can charge high power devices anywhere    - Conatains Lion Batteries (limited lifespan 1-2 years)
   - Doesn't need sunlight (internal battery)         - Not Completely Eco-friendly
                                                                             - Takes a long time to charge internal battery

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Step 1: Tools & Materials

Picture of Tools & Materials
The links below are just alternatives since the stores where I bought my parts where just available localy in the Philippines. When converted into PHP to USD the price of my spendings would become $5! It's real cheap. The solar panel only cost me $3.

Materials: (Click on the link to see where to buy)
- 6V Mini Solar Panel
- 5V Step-Up/ Inverter USB Charger Circuit ($3
- Your Smartphone (for testing)
- Your Phone's Charger Cable (Interchangable)
- Flexible and Foldable Plastic Card (for stand)

- Hot Glue Gun
- 30W Soldering Iron
- Leatherman Multitool

Step 2: Choosing Your Charger Module (UPDATED!)

Picture of Choosing Your Charger Module (UPDATED!)
sku_219931_4 (1).jpg

Step 3:

Picture of
The USB charger circuit came from a cheap old iPod USB charger. The main chip is similar to the well known MAXIM inverter chip. The circuit is a step-up/ step-down regulator, meaning when the power supply is underpowered it tends to boost the voltage but when the power supply is overpowered it limits the output voltage. It's ideal for solar powered purposes.

1st.) Dissemble a 12V High Power USB Charger.
2nd.) Cut the wires, short enough to be mounted on the solar panel.
3rd.) Solder the charger circuit to the solar panel (Adding a switch is optional).
4th.) Use a hot glue gun to mount the charger to the solar panel.
5th.) Be sure that the USB port is not protruding and the circuit should not touch any other leads on the panel.

Step 4: Adding The Foldable Stand (optional)

Picture of Adding The Foldable Stand (optional)
I recycled an old gaming prepaid card and bent it with a ruler. I also hot glued it to the right side of the solar panel.

Step 5: You're Done!

Picture of You're Done!
Now enjoy being completely independent from the power grid. I forgot to tell you that I have an interchangeable USB charger cable for Apple 30 pin, Micro USB, Mini USB, Samsung, Motorola, and Nokia, you can find one in your local dollar store. 

You can now carry your own personal solar powered charger anywhere. It's also a perfect survival kit since sunlight never runs out :)))) Have fun! :D

I didn't realize that my last solar projects were unconsciously inspired by your project of one year ago, indeed I had it in my favorites :-) but I didn't remember that! Well done, awesome project!

I did a very, very simple version of this, by simply gluing a Powerbank to the back of a 4.5 V solar panel. The output from the solar panel goes into the Powerbank, and then when I want to charge something, I unplug the panel from the Powerbank, and plug my device in. However, I feel it's not charging properly, and also, I want to find a way to put a display of the power output on it. Any suggestions?

fbiletta1 month ago
No, I just soldered those two components with wires, as you did
fbiletta1 month ago
Hi, yesterday I connected tis solar panel ( with the first charging module of the step 2.. But it doesn't charge at all my iPod, but the strange things is that my Nokia lumia, when it's connected, show the charging icon on the battery as usual, but it doesn't charge a bit, even after 2 hours. What should I do??
ASCAS (author)  fbiletta1 month ago

Do you have the booster circuit installed?

jerryrard3 months ago
Bilib ako sa pinoy!
stubbsonic3 months ago
I wired two panels in series and got 12.7 V on a fairly sunny day.

I connected the side part of a 12V car charger to the negative on one panel, and the tip of the charger to the positive on the other panel. When I tested the voltage on a USB cord, I got -5V. But ordinarily I think it is supposed to show +5V. Do I need to switch the wires to make this work correctly?
dawelge7 months ago
Are you using a 5v or a 12v? I tried a 5v like in the picture with a 6v 1w 168mA and it will not charge my cell phone. Is there something else that I need?
codegamc dawelge5 months ago
that is, unless you buy a charger to modify that works with an iPhone
codegamc dawelge5 months ago
most iphones, if your phone is one, have special circuitry that apple put in that changes the voltage (on the charger end) to a few voltages as soon as a phone goes in, like a code, that the iPhone, iPod, iPad etc, "reads" to ensure its an apple-approved charger
ASCAS (author)  dawelge7 months ago
I'm using a 5v regulator. Do you have a step-up regulator?
ASCAS (author)  dawelge7 months ago
I'm using a 5v regulator. Do you have a step-up regulator?
Jorghe10256 months ago
So the charger circuit you used is a regular dollar-store USB car charger? and if so, you think it will work with this solar panel?
ASCAS (author)  Jorghe10256 months ago
Yes, but be careful in selecting chargers, I got lucky and I found a maxim based (stepup reg.) Well that device on your link, has enough power to charge USB devices without the regulator.
sbanerjee57 months ago
Hi, I have the same question. I have a 12V - 5V dc-dc car charger. will that work for this. I am not sure if the circuit works if the solar panel puts out a less than 12V voltage.
nickpar208 months ago
For 12v usb charger circuit would a car USB charger work?
That is a darn good question. I happen to have found one and would be interested to know this as well!
mnugnes8 months ago
hi there, i will go to the seeside in one week. i need to build one but i dunno where to buy the 5volt to usb charger circuit.... is there any chance to find it inside one of the emergency battery charger?
ASCAS (author)  mnugnes8 months ago
I updated the guide a while ago, check out step 3. The link if the store is provided.
Free Shipping
Sjoerd X8 months ago
I would like to make a phone charger with batteryfuction, prefered a supercapacitor, to get things working, would the following mod of your project work?:

- Solar panel (6V?) +
|                                              |
|                                              |
|                                              |
| super cap, blocking diode |
|                                              |
|                                              |
|                            switch, for less leaking current when not charging USB
|                                              |
|                                              |
|                                              |
- your "12v" to usb module +
ASCAS (author)  Sjoerd X8 months ago
Yup! But could you draw a schematic of your idea.
Sjoerd X ASCAS8 months ago

U=(1/f) * {I*dt} (capacitor formula)
I = U*f/t (asuming integral {I*dt} = I*t

E=U*U*F= 5.4^2*F
E= U*I*t = 5*1.3*3600 (my battery has 1300mAh, is 1.3 ampere for 3600 seconds/1 hour)


U=voltage, F=capacity, I=current, dt=infinitdecimal time, t=time, E=energy,
ASCAS (author)  Sjoerd X8 months ago
BTW, I updated the guide, there's a link above, of the USB Step-Up Inverter.
No need for formulas, well the capacitors acts as a small-time power line filter. For the Rectifier Diodes, the 1N4007, is a cheap & reliable 1A diode.
iTardis9 months ago
Would I be able to make this without the circuit?
lawroman9 months ago
ASCAS, you left out some important detail. Can you tell us what name brand or model number of that 12V USB Charger ?
akitagawa9 months ago
Hi. Can u pls tell me where to get the charger circuit. If not can u tell me how to know if its the same circuit. Thank you
geewizard9 months ago
how did you get the usb charger circuit out of the casing?
How are you able to use a 12V charging circuit with a 6V solar cell? That doesn't seem to make a lot of sense. Wouldn't it be easier to use a DC to DC boosting circuit instead?
ASCAS (author)  JoshuaZimmerman10 months ago
If your'e familiar with the joule thief, the circuit almost acts just like it except there's a regulator feature.
dgomez1810 months ago
Pleaseee, provide us a link for USB charger circuit. Could you please, explain better that item? Whats integrated in that chunk you cut?

Thank youuuu
hjain310 months ago
how to get usb charger circuit.can it power raspberry pi. ???

kindly provide link for usb charger circuit..

Thanks for wonderful and simple post
stubbsonic11 months ago
I ordered two of those solar panels. Is it ok to wire them in series to get 12 volts?
ASCAS (author)  stubbsonic11 months ago
Yes! The charger will regulate the circuit.
stubbsonic ASCAS11 months ago
The charger will output up to 1A when connected to a 12 volt cigarette lighter socket. One panel is only rated at 120 mA. I'm wondering if this will double the current?
msel11 months ago
Hi this project that what I need, I was going to buy like this gadget but I wont now :)
I want to make same but I havent this part: " Torn Apart 12v USB Charger Circuit " do you give me circuit diagram ?
tutdude9811 months ago
well this is kind of charger that i need for traveling because it doesn't have battery and its lighter but usually i use my tablet in car,or when i camping and it draws about 2 amp when charging so i need battery backup on solar charger so i started to do my 5v USB and i can plug this for charging internal battery
ASCAS (author)  tutdude9811 months ago
You can use a 3W solar panel, that's enough to charger one tablet without having a battery reservoir. I actually have one, I've tested it by charring three devices simultaneously (iTouch, iPod, Android Phone). The 3W solar panel also works with our iPad 1st gen. Cheers!
tutdude98 ASCAS11 months ago
yes but still it will charge my charger battery over day when im using tablet and charge it over night when im not using it
and on step 1 "Torn Apart 12v USB Charger..." you've put Cherry Mobile Flame 2.0 Review :)

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