Picture of Simple, Cheap MP3 Player Solar Charger
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This is a really simple tutorial on how to make a solar charger for your MP3 player. This won't work with an iPod touch (The iPod ignores it, it's not an apple product), but should work with most generic players. I use it for my CreativeZen player.

I bought my solar cells HERE. It's the best prices I can find, plus free shipping!
This panel charges @
5.13 Volts
.8 amp to 1 amp; in full sun

Because MP3 players have built in battery savers, there is no need for an electronics board or battery sensor. It's physically impossible for the solar cells to spontaneously produce a higher voltage. If the voltage drops (for whatever reason) the MP3 player automatically disconnects the battery.

MP3 players automatically disconnect the battery before it overcharges
MP3 players will not discharge into the panels, they have built in diodes.

Putting it simply, the very worst that could happen is that it won't charge the player.
But I still have to say: do this project at your own risk :)

Step 1: What You Need

Picture of What You Need
1) 9 x 1 amp, .57 volt solar cells. I bought mine HERE
2) Tabbing wire or fine electronics wire. I bought mine HERE

3) 8 x 10 cheap plastic picture frame from Wall Mart
4) USB extender with female USB adapter. $1.00 at Dollar Tree.

Wood/foam core,Solder, flux pen/ normal flux, soldering iron, and soldering skills :)
I recommend you wear latex gloves when you work with solar cells. Fingerprints look bad...

snotty5 years ago
Nice work!

Here's how you can make it work with an iPod:
Connect the two middle USB pins to about 3 volts. Do this by making a voltage divider. Make a voltage divider with two 100k ohm resistors (Brown - Black - Yellow). Connect one resistor to +5volts and the other end to the middle two USB pins. And connect the other resistor to minus, then connect the other end to those same two middle USB pins. Easy eh? Here's a diagram.

The Mr. Buzz USB charger uses this type of voltage divider as well as two 1uF ceramic capacitor somewhere in there but I have had some (limited) success without the capacitors.

Does anyone know if those capacitors really necessary?

Also some devices need a minimum rate of amperage in order to charge. What I did was trickle charge 4 AA NiMeHy batteries with a small 6v panel and a diode. Then I plug this into my iPod touch. The NiMeHy batteries provide the required amperage.

ipod charger1.jpg
If you had enough current to supply 1A (1000mA), if you made a voltage divider to supply 3v to the green data wire and 2.2v to the white data wire. Which is:

150 ohms (brown green brown) from red (5v) to green
100 ohms (brown black brown) from green to black (0v)
220 ohms (red red brown) from red (5v) to white
270 ohms (red violet brown) from white to black (0v)

I needed to do this to get my homemade charger to charge my iPhone 4, iPod touch, and iPad 2. It charges just as fast as the apple charger, and I'm actually using it as I speak :) just be sure you can source 1A of current, and you'll be fine. I also used a switch, 5v regulator, and power indication LED in a metal zippo container.

PS any properly sized resistors would do. Ex 100 ohm and 150 ohm has the same effect as 10k ohm and 15k ohm or the same as 1M ohm and 1.5M ohm. The larger the resistor, the less wasted energy in the divider.
Todd Gehris3 years ago
As a precaution you could add a diode on the plus side of the panels to prevent a device's battery from discharging into the panels. It also would be safer to devices to have the power out of the panels regulated. It takes very few components to do that. If you really wanted to get fancy you could hook a few rechargeable AA batteries up to it as well to compensate for when the panel gets shaded.
songrotek4 years ago
It's really cool!
mariosk8s5 years ago
Cool instructable. I gave this a whirl this weekend: http://twitter.com/mariosk8s/statuses/13699610704 
nepheron (author)  mariosk8s5 years ago
 Twitter won't let me see the picture, I'd need an account. Could you post the pic here? 
did you know that you can use a magnifying glass to upgrade power!
I did some tests if you don't use those cheepy once they won't burn when aplying a magnifyer if you hade a biger magnifying glass then it would give more power to!!
Can't seem to upload images. Posted it here:
nepheron (author)  mariosk8s5 years ago
 Wow! thats amazing! You did a great job. Where did you get your cells?
It's a really nice panel :D I love to see pictures of stuff people make :)
Thanks. Got the cells the same place you got yours. I just followed the link you placed. Worked out well.
nepheron (author)  mariosk8s5 years ago
 Twitter won't let me see the picture, I'd need an account. Could you post the pic here? 
drakesword5 years ago
I <3 my creative zen.

You should be able to substitute the cells you bought with ones salvaged from solar garden lights. I'm pretty sure you can cut most of the resin down to make them smaller. 3.0v @ 50ma each.

Make strings of 5 in series to get 15v then as many as you want in parallel to get the current you want. With a few of voltage regulators and diodes you can charge 12v 9v 5v and 1.5v

Once my collection is large enough I plan on doing that. If there is no instructable I will post one.

nepheron (author)  drakesword5 years ago
 I've made a solar panel from garden lights I found at a yard sale. It charges at about 6 volts and fairly low amperage...takes awhile to charge the player, but it does work!!
fortunetly with my line of work I run into them all the time. If you hook the solar cells (a current source) and series it will produce more voltage. If you hook them up in parallel it will produce more current. What I was saying is if you can get a lot of them.  5 in series to produce ~15v @ 50ma in parallel with more identical strings. So 1 string would be 15v @ 50ma, 2 15v @ 100ma, ... 10 15v @ 500 ma which is what a standard usb port will output (unless the device requests more in which 750ma)
nanosec125 years ago
Nicely written 'ible, but I do have one comment:

I appreciate the fact that you sourced your suppliers and included links, but was it really necessary to link them several times each throughout the steps?  It seemed to me that you were almost at the level of getting paid to link them, with the number of times that you did.

Other than that, nice Instructible
nepheron (author)  nanosec125 years ago
 Oh LOL I see what you mean, about there being too many links. I inserted a step after i was was finished, and accidentally left the repeated information...thanks for catching that :D
Barcode805 years ago
FYI, if you search for some 'ibles about building homemade chargers, you'll find the simple info to have the ipod touch work too. It's something to do with making the voltage divider if I remember correct. Nice work!
KT Gadget5 years ago
One possibility why the Ipods are not charging is because they do not have a built in voltage divider which tells the ipod when it is "charging" and "full." Most older ipods used to have the built in divider because I had the first generation nano (or it could have been my Ipod mini back in the day) and it used to charge, on DIY battery chargers I made, without it. With my 3rd gen, however, it does not see that its being charged and hence does not show the indicator for it.

I just researched about the divider so I assume the older Ipods had them built in and I have not tried it myself due to school and other projects I'm working on, but when I have the time I will try it out myself.

Great instructable btw, those solar sells would be a good investment on a battery- free amplifier.

nepheron (author)  KT Gadget5 years ago
 A battery free amplifier is something I've been thinking about! I have a little ipod speaker I got from Goodwill, so I may make the modification!
Nerdz5 years ago
Cant seem to reply to myself, but nice job :D
Nerdz5 years ago
look on ebay for solar cells, theres a ton there.