HOW TO – Make a solar MintyBoost, a solar power charger for your gadgets!

Previously there was a very popular Instructable on making your own “Solar MintyBoost” – before you needed to get parts from various places, now you can get them all in one spot – at the Adafruit shop!

So – if you want to make solar MintyBoost, here’s how

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Pick up a USB/Solar LiIon/LiPoly charger and Lithium Ion Polymer Battery – 1200mAh. A 1200mAh lipoly will provide as much overall power (~4.5 Wh) as 2 rechargable AA’s.

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Choose from either a 1W or 2W solar panel. Either will work, if you are using the smaller panel, we suggest removing R4 and replacing it with a 6.8K (or so) resistor which will keep the lipoly charger from trying to draw too much current from the panel.


Next up, you’ll need a mini-B USB cable to sacrifice. Use the one in the shop or find one in your room.

Follow the tutorial on our site for how to splice the solar panel into the USB cable.

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Finally, a MintyBoost will give you a USB 5V output! Connect the other side of the JST cable from the LiPo charger into the input of the MintyBoost.

Put the panel out in the sun and watch for the charging light to go on. then when the battery is charged up, the DONE led will be lit.

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You can put all this in our new Altoids mint-sized tin!

Note: While it may most devices, this will mostly likely not work consistently with the iPhone 3Gs and/or the iPhone 4. We will have a new MintyBoost and MintyBoost “rechargeable” soon, if you need to support those two devices specifically hold off until you see these new versions of our kits on our site.

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  1. I have one of your two-watt panels.

    What I want is a solar panel that is 3.5"x2", the size of an Altoids tin.

    Or maybe a 5"x6" tin to fit the panel. But that would be a lot of mints to eat…

    (by the way, your captcha always rejects my first answer. On the second try, I just noticed that the color code changed when I started to move the slider. I’m using Firefox)

  2. check out works nicely with the smaller 1W panel

  3. Sweet! I put up a link on the instructable tools and materials page.

  4. scr5eamineagle

    Ok, so I’m still learning, and all these resistor properties are making my head spin here.
    I plan on making this entire kit from the solar panel to the minty boost but I’m going to use the smaller solar panel so I can keep it all compact.
    What I need to know is what do you mean by "removing R4 and replacing it with a 6.8K (or so) resistor"? Do you mean the R4 resistor from the mint boost kit? Or do you have to build the LiPol charger and replace an R4 position resistor?
    Not to show my infancy in electronics. A 6.8K resistor would be one with a banding of Blue, Gray, Red, and the last one will either be yellow(5%),silver(10%),or gold (20%)tolerance, or a 6,800 ohm resistor (+/- tolerance). Is that correct?
    Oh, and what is the "or so" about?

  5. the lipoly charger is prebuilt, but if you look carefully you will see there is a way to solder in a thruhole resistor in spot R4 – this can change the charging rate. by adjusting the charge rate you can get the best efficiency from your panel.

    “or so” means that if the shop doesnt have exactly 6.8K you can vary it by up to 10 or 20%

  6. what type of devices can I charge with this? what about a digital camera or gps?

  7. I just want to say how much I love your captcha.

  8. I just posted for the sole purpose of saying:
    I LOVE your captcha!

  9. Don’t you think that the minty boost risk to over drain the battery?
    Minty boost works with very low voltage wich is way less than the lower voltage limit of lithium batteries.

  10. fdufnews:

    Most Li-poly batteries have a built-in circuit to prevent over charging and over discharging 😉

  11. anyone know if this works with iPhone 3Gs or 4?

  12. Is there away to charge the battery pack from house power? I do a good deal of hiking and would like to be able to leave with the battery fully charged and then charge it from the solar panel when needed. THanks for you help!

  13. @mark – please post this type of question in the forums, thanks!

  14. Another quick question. Have you tried any of the flexible/rollable solar panels with this?

  15. @mark – please post this type of question in the forums, thanks!

  16. adafruit…
    Will this work with an iPhone4 if you have the v4 MintyBoost to recharge? There is a disclaimer at the bottom of the description that states:

    “Note: While it may most devices, this will mostly likely not work consistently with the iPhone 3Gs and/or the iPhone 4. We will have a new MintyBoost and MintyBoost “rechargeable” soon, if you need to support those two devices specifically hold off until you see these new versions of our kits on our site.”

    Is this true or is this just old and the v3 addresses this issue?

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