5-12 v dc lipo charger wont work with solar panel

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dizzer
 
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5-12 v dc lipo charger wont work with solar panel

Post by dizzer »

hello,
i just completed a solarmintyboost using the 5-12v dc lipo charger ,the 6v 2w solar panel ,a 6600 mah 3.7 v battery and ofcourse the mintyboost.
so here's my problem the lipo charger work great on usb (charging light goes on and mintyboost gets powered) and the battery works fine too.
but when i connect the solar panel http://www.adafruit.com/products/200 (i mounted a mini usb on it) , the power light will go (even bright) on, but the charge light won't.
sombody please help.

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Franklin97355
 
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Re: 5-12 v dc lipo charger wont work with solar panel

Post by Franklin97355 »

Have you measured the actual voltage and current being supplied by the panel? It probably won't be the rated value as that is best case.

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adafruit_support_bill
 
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Re: 5-12 v dc lipo charger wont work with solar panel

Post by adafruit_support_bill »

Have you put the panel out in full sunlight? You won't get enough solar energy to charge under a desk lamp or through a window.

dizzer
 
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Joined: Tue Apr 03, 2012 12:50 pm

Re: 5-12 v dc lipo charger wont work with solar panel

Post by dizzer »

Thank you for replying . I have only tested it whit a lamp but the weird thing was that the power light on the lipo charger wil go on bright but the charge light not at all

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adafruit_support_bill
 
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Re: 5-12 v dc lipo charger wont work with solar panel

Post by adafruit_support_bill »

The panel is producing enough voltage for the power detect circuit, but not enough current to start charging. This is typical of solar panels. This is described in detail on the design page.

Image
The Green lines show the I-V curve of the panel for a given light condition. As the light increases the voltages stay sort of the same but the amount of current you can draw goes up! If you can keep the DC/DC converter operating on the red line, that's the maximum power.

dizzer
 
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Joined: Tue Apr 03, 2012 12:50 pm

Re: 5-12 v dc lipo charger wont work with solar panel

Post by dizzer »

Thank you very much. This bassicly means i need to keep it in the sun for a while?

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adafruit_support_bill
 
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Re: 5-12 v dc lipo charger wont work with solar panel

Post by adafruit_support_bill »

Once you get it into sufficiently strong sunlight, it should have enough current to start charging the battery. At that point you should see the charge light come on.

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