loading

Phones tend to be out of battery right when you need them most. With this project, you can extend your phone's battery life just enough to make those emergency calls! You just have to set your phone out in the sun for a while, and you'll have just enough power to send a text or make a short call.

Step 1: Materials

  • To modify your phone, you'll need the following:

  • An approx. 2"x2" solar panel I got mine out of a broken electronics kit

  • A dremel w/ cutting disc I got mine at Harbor Freight Tools

  • A Smartphone The project can also be done with a typical phone.

  • Electrical tape In my case, all I had was bright red, shiny tape. This made for an interesting project.

Step 2: Cutting

Open up your smartphone, until you reach the back. My smartphone was a ZTE Majesty, so all I had to do was pop off the back with my fingernail. Unfortunately, not all phones are this easy to open, but you should be able to find instructions here. Regardless of the type of phone, you need to reach the very back panel of your phone. Using a Sharpie, trace the perimeter of your solar panel onto the inside of the very back panel of your phone. Using your dremel, cut out the outline.

Note: It is better to make the hole too small, than too large. You can make a hole larger, but you cannot make it smaller.

Sand the edges of your hole until your solar panel fits into place perfectly. Be careful not to scratch the back of your phone with the sandpaper.

Using electrical tape, tape the solar panel into the hole from the inside, positioning it so that the actual "solar collector" faces the outside of your phone, as shown.

Step 3: Wiring

Run the wires to your battery terminals, making sure to connect the red wire to the positive contact, and the black wire to the negative contact. You can solder the wires if you want, but all I did was place them against the contacts and press the battery into place, thus securing them in the proper position. Clip the back of your phone back into place. This may take a little persuasion considering that it is now slightly more bulky than it was at the beginning of the project. Enjoy your Solar-Assisted Phone!

Update: Thank you to user "depmode" for giving me inspiration to draw the circuit schematic. As best as I understand it, the diode will help prevent electrical backflow.

Update No. 2: User "chubby8" said, "I think it would be safer to find a solar panel with 5v -12v output, and use a 5v regulator and a diode, and then solder it to the inside of the USB charging socket. +5v to the +5v pin, ground to the groundpin (or any ground on the board). Your phone will then regulate the charging of the battery.You could maybe use the solar panel you have along with a joule thief to step up the voltage, followed by a 5v voltage regulator but I'm really not sure.Best case scenario is it won't charge the phone very much, even on a sunny day.Your current setup won't charge the battery, only risk damaging it and possibly your phone as well. But well done for having a go, hope this helps!"

Considering chubby8 probably knows more than I do about electronics, please follow the above instructions. Thanks!

I am a beginning electronics hobbyist, and want to improve my instructable projects. Please comment, suggest improvements, or point out something I unwittingly missed! Thanks!

<p>Hi! Very nice instructable!</p><p>I have some experience in electronics and have a couple of comments if you don't mind.........</p><p>I would recommend adding a blocking diode (1N4007 or similar) from the solar panel to the battery for two reasons. 1. It will help protect the battery if the panel wires ever get crossed or short circuited for some reason, and 2. It will lower the solar panel voltage by about 0.6Volts. Those types of solar panels are usually around 5 Volts. The lithium-ion/polymer battery in your phone does not like to be over charged and a 3.7Volt cell is normally charged with 4.2Volt. The blocking diode will at least drop your panel voltage to 4.4Volt. Luckily there isn't much current available from these panels, otherwise I would have recommended you not try this, as these batteries can have what is know as thermal runaway from over charging.</p><p>It is still a brilliant idea and worth much looking into...</p><p>Also, you have excellent pictures accompanying your able!</p><p>Thanks very much for this able and keep them coming!</p>
<p>At the beginning of the project I wasn't entirely sure whether or not a diode would be necessary, but now I understand better why I would need one. Thank you for the suggestion! </p>
<p>That's really good idea! I was thinking of making something like this about a year ago but I found out that none of the solar panels I had could supply enough current, How much can yours supply?</p><p>I'm not sure that you need the diode, I'm pretty sure that your phone has one already for that purpose... But it's better to be safe than sorry</p>
<p>This is a good idea &amp; also that's why i always read all comment, as most of the time I can learn more.<br>Thanks a lot for the 'ible !</p>
This is nice. I actually planned on doing this but I have a galaxy note 4 and I don't wanna risk damaging the aesthetics of this phone. Plus the heat to the phone during sun charging.. Not so good. And of course it will be stolen if I left it charging in a public place and I turned my back for around 20 seconds. Literally a hot seller, hehe. Good instructable tho and we all look forward to your continued skills and future instructables.
<p>Hi, I have a question. My phone's battery has got three pins and my phone pins are three, too. But, according to the solar panel, we have 2 pins as they (+) and (-). What should I connect them truely? It was confusing me to connect pins correctly. What is the pins duty to be as three instead of two? Thank you.</p>
Hello,<br> I'm not the most experienced in electronics but I'm sure lithium ion batteries (like the ones found in nearly all mobile devices) require special charging circuits. lithium ion batteries will be damaged if over charged, or even if there voltage drops to low. They can be quite dangerous if charged improperly or shorted as they can &quot; bubble up&quot; and burst, get very hot and even catch fire. <br><br>I think it would be safer to find a solar panel with 5v -12v output, and use a 5v regulator and a diode, and then solder it to the inside of the USB charging socket. +5v to the +5v pin, ground to the groundpin (or any ground on the board). Your phone will then regulate the charging of the battery.<br> <br>You could maybe use the solar panel you have along with a joule thief to step up the voltage, followed by a 5v voltage regulator but I'm really not sure.<br><br>Best case scenario is it won't charge the phone very much, even on a sunny day.<br><br>Your current setup won't charge the battery, only risk damaging it and possibly your phone aswell.<br><br>But well done for having a go, hope this helps!
<p>Hi!</p><p>Very nice circuit.</p><p>I'm sorry, I should have given some more info about how to connect the diode. ;-) As it was just a suggestion, I didn't think more detail was needed. If you want I can explain a diode and its function in a little bit more detail....</p><p>I just want to mention that for this system to work, the solar panel voltage will have to be higher than that of the battery. If you only have 1.5V from your solar panel, the battery, which is let's say at 3.7V, will try to &quot;charge&quot; the solar panel as it has a greater potential (Voltage). The diode prevents this from happening.</p><p>Kind regards!</p>
Thank you for explaining! I'm always trying to learn through instructables, and you have been a great help.
<p>It's a great pleasure! That's why we are all here afterall!</p>
<p>Nice work ! In my opinion you should put a diode like in a following schematic .</p>
<p>O.K. I've never drawn a schematic before, but with yours as a model I should be able to do it. Thanks for the idea!</p>
What's the voltage of the solar panel? Did you measure it? In my ecperience this solar panel in full sun gave me 1.5 V perhaps yours is better. Regards and keep doing inovative stuffs.
No, I did not measure the voltage, although I would approximate it at about the same as yours. I just assumed that it would provide little enough current to not damage the phone, yet just enough to charge it slowly. Thank you for the comment and the compliment!

About This Instructable

8,616views

216favorites

License:

Bio: I am a maker. As founder of MakerBlog, I enjoy sharing my creations with others.
More by funtogether:3D Papercraft Heart -- Without a 3D Printer! Spill-Proof Monopoly Board Toothbrush Wall Holder - Using Oogoo! 
Add instructable to: