DIY Solar USB Charger - Altoids

Step 11 Enjoy

Now you're done.  Enjoy the fact that you're being very green and clean.

Also, before someone chimes in... yes I do know batteries are not entirely green.  If you want to be super green you should use some super capacitors for this project.  They last forever, are super green, but are also quite expensive.

What I like about this project is that it's simple and handy.  It makes for a nice gift.

If you need any parts you can always get them from my website, BrownDogGadgets.com.  All the money I make goes to doggy treats and more projects.

Thanks for reading!

Comments

[swimfan2489]

Great instructable! This has inspired me :)

I am looking to build a slightly different version of this instructable, but with supercapacitors instead, to make this "super-green". Do you know if it would be possible to just use supercapacitors to completely replace the batteries? Even if it would only work while in the sun, that would be fine with me... Any help would be great!

[joewein]

If you're worried about how "green" the components are, the NiMH battery is not the #1 candidate for concern: Unlike lead acid and NiCd cells, NiMH cells do not contain toxic heavy metals that need to be kept out of incinerators.

The biggest environmental impact will be the energy used to make the refined silicon for the solar cell, most likely from coal burnt in China. Switching to super caps would not resolve that.

[JoshuaZimmerman]

I don't see why not. You'd have to have solar panels to provide power, but I don't see why not.

The only downside is that super caps cost a lot of money compared to just using some AAs. Plus because of how little power this thing uses a set of AA batteries would last a very very long time.

[JoshThebBoss]

Will this work for Ipod touch 2nd Generation and ipod touch 4?

[diy_bloke]

if you get the right MintyBoost it may:
http://www.ladyada.net/make/mintyboost/changelog.html

Apple has apparently changed and rechanged their load protocal to make it difficult to charge. Adafruit has tried to keep up with it.

[JoshuaZimmerman]

No idea.

[JoshThebBoss]

What wires am i supposed to solder the USB cirquit ?

[Thermiter]

There is also the issue that supercaps do not hold as many watt-hours of power as batteries do and they have no internal resistance. So, in addition to putting a 1+ watt dissipation resistor across the caps, a flagrant waste of power, but a necessary element, you would not get nearly as much charge out of them.

[MorNiLachnan]

If I wanted to do this but use 1 or 2 of the cheap solar yard lights from Lowes as donor parts, what would I need to modify? Do those have the right diode in them between the solar panel and the battery pack? Or is that irrelevant due to the USB circuit?

The ones I bought for the yard claim to be 4x bright. What would be the proper way to determine if I need 1 or 2 solar cells of these? Just test output of the panel with a voltmeter?

[JoshuaZimmerman]

The only thing you'd be taking out of the garden light would be the solar cell. (You could use the batteries, but they usually are low capacity and not worth their weight.)

You'd still need to get all the other parts. AA holder, 2 AAs, diode, wires, charging circuit.

Plus you should really use a multimeter to figure out what the voltage of your solar cells is. You need a combination that is greater the 3V. The bigger the better.

[JoshThebBoss]

What wires am i supposed to solder the USB cirquit ?

[didooo]

deneme