Solar Powered Minty Booster Moderators: adafruit_support_bill, adafruit

[Jman23]

hey
i am building a solar powered minty booster and i have completed constructing the newest minty booster. i am now unsure of where to connect the red and black wire from the Solar Lithium Kit to the Minty Booster batteries. Ive looked at both https://learn.adafruit.com/usb-dc-and-s ... ly-charger and https://www.adafruit.com/products/390 and i just cant seem to figure it out. Please Help
Thanks

[adafruit_support_bill]

You connect the "Load" outputs of the solar charger to the battery inputs of the Minty Boost.

[Jman23]

righto, another dumb question but do u connect it to the input holes on the circuit board of the minty booster or the battery holder?
thanks again

[adafruit_support_bill]

You can go right to the input holes on the board. Double check the polarity and make sure you connect positive to positive and ground to negative.

[jyarnall]

Hi,

I have bought the mintyboost kit V3.0 for my students at school. I don't really know anything about electronic. I would like to attach a solar panel to them (I have 6V ones). How can I amend the instructions to add in the panel. Do I need to buy anything additionally, or exclude/ add in additional steps.

Thanks!

[adafruit_support_bill]

The MintyBoost is not compatible with a 6v solar panel. The max input to the Minty is 5v. The MintyBoost also does not know how to make efficient use of a variable sources such as a solar panel. For solar charging, you really need a charger designed for the purpose: https://learn.adafruit.com/usb-dc-and-s ... sign-notes

[jyarnall]

Thanks for the information. I don't really understand what that webpage means. I have looked at your solar one, and the one I have bought. There is no way to use the equipment I have bought and alter the procedure to connect it to a solar panel? Unfortunately I am not an electronic teacher, so all that information doesn't really mean anything to me...Is there any way you can explain it? Thanks

[adafruit_support_bill]

The problem is that the MintyBoost was designed to work from batteries. And batteries behave a lot differently than solar panels.

The MintyBoost will try to pull as much power as it can from the batteries to satisfy the demands of what you plug into it. The batteries will do the best they can to provide that power - until they gradually weaken and become exhausted.

Solar panels are different than batteries. At any point in time, the power they can provide depends on the amount of sun hitting the panel. And to make things more difficult, if you try to pull more power than they are capable of producing, they more-or-less give up. In this case, the voltage drops dramatically and you get little or no power at all. So you need a special circuit that can sense how much power the panel is capable of producing at any given time, and not try to pull any more than that.

[jyarnall]

Thank you , well explained. So there is no alternative to the equipment provided, and adding or subtracting anything to the kit? I have looked at other kits online and they use similar items:
USB Charging Circuit - Works with all iPhone and iPod models, as well as most other phones and USB gadgets.
6V 80mA Solar Cell
3 AA Holder
3 Rechargeable AA Batteries @ 2600mAh
Toggle Switch
Wire

most of which are in the kit - just not the switch

Thanks!

[adafruit_support_bill]

Not sure what other kits you are looking at. But the design of the charging circuit is what makes the difference.

While it is possible to power the MintyBoost via a 6v solar cell. The results would be less than optimal. But then, there may be a lesson in that too...

[jyarnall]

Good to know. Thanks Bill.

[da3v3d]

In this thread, and in the picture from learn USB, DC & Solar LiPoly Charger project, the MintyBoost is connected to the output of the Solar LiPoly Charger.

On a sunny day, I see 6V across the output of the Solar LiPoly Charger. Based on the LT1302 data sheet, it looks like my trusty MintyBoost might be able to handle 6V, but whatever is connected to the MintyBoost will see 6V, not 5V in full sun, correct?

My plan is to power a photon and some neopixels, and I am guessing that 6V might be at the upper limit of what they would tolerate.

By day, the photon + sensors seem to be drawing about 0.03A, and at night, they would be drawing approx 0.45A when the neopixels are on (and the danger of 6V coming out of the solar panel is significantly lower). During the day, we tend to alternate between bursts of bright sun and bursts of cloudiness, so it would be ideal to maximize charging (within limits of what the batteries can handle) when the sun is available.

I've seen suggestions to connect the minty boost in parallel with the battery instead of the output of the Solar LiPoly Charger, and I've also seen suggestions involving series diodes to drop the voltage, zener diodes to clamp the voltage, 7805's, and whatnot. I was also wondering if just putting a verter between the output and my photon/neopixels would be a clever solution, or a bad idea. (I have a hard time telling those two apart.)

My gut tells me that either putting the MintyBoost in parallel with the battery, or putting a verter between the Solar LiPoly Charger and the photon would be the way to go, but my gut usually has just enough knowledge to be dangerous, so I figured it would be a better idea to ask someone who is more knowledgeable about these things. Which do you suggest?

Thanks!
-Dave

[adafruit_support_bill]

The Verter is a good solution. It operates in either buck or boost mode - depending on the input voltage.
Wiring the MintyBoost in parallel with the battery is also a reasonable way to go. The only downside to that is the MintyBoost & Photon will be sharing the charge current to the battery, so the battery will charge more slowly.

[Habibka]

Fast question. I looking for solution like Solar Charging Hand.bag or something like this:

http://picasaweb.google.com/104170461214226700553/SolarMintyBoost_2010#

I wanna ask if can order the "Solar Charging Hand.bag" all component at ones or i need to order everything one by one.
If I have to do it one by one can you help me to don't miss something.

P.S is it compatible with smartphone Sony Z2

Thanks and apologies if question is not in the right category

[adafruit_support_bill]

We have the original solar charging hand-bag tutorial which was based on the MintyBoost:
https://learn.adafruit.com/solar-chargi ... g/overview
As well as a newer one based on our PowerBoost boards.
https://learn.adafruit.com/solar-boost-bag/overview
The PowerBoost board used in the second tutorial will perform better with many of the more modern phones.

In either case, the products used are listed on the right. If you scroll down near the bottom, there is an "Add All To Cart" button.

Note that the list will include some tools as well as the electrical components. If you already own the tools, you can remove them from your cart.