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USB, DC & Solar Lipoly Charger
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

USB, DC & Solar Lipoly Charger

by ko4nrbs on Wed Apr 27, 2016 9:14 am

Can the USB, DC & Solar Lipoly Charger be used with Protected cells?
Bill

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Re: USB, DC & Solar Lipoly Charger

by adafruit_support_bill on Wed Apr 27, 2016 9:17 am

As long as they are 3.7v nominal (4.2v full charge) Lithium cells. All of the LiPo cells in our store have protection circuits.

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Re: USB, DC & Solar Lipoly Charger

by ko4nrbs on Thu Apr 28, 2016 8:22 am

I need a charger for 18650 Li-ion cells that I can use a Solar Panel with. For this application the cells would be left connected to the Solar panel/Charger and connected to a digital camera for external power. The charger would be used to maintain the charge on the cells. It would have to be able to operate with power interruptions depending on the amount of sunshine available. In other words begin a proper charge when adequate power is available with proper charge currents. Some chargers will lower charge current when restarting a charge after power has interrupted. In addition many chargers will not restart a charge unless power is removed and/or the cells are disconnected.

Sounds like your charger meets all my requirements.

Any chance it could be modified to charge LiFePO4 26650 cells in the future? Charge voltage would be 3.6 volts.

Bill

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Re: USB, DC & Solar Lipoly Charger

by adafruit_support_bill on Thu Apr 28, 2016 9:40 am

Charging a 3.6v cell would require a different charge controller chip. The MCP73871 can only be configured for cells as low as 4.1v. But I will mention it to the design team. There may be a LiFePO4 charge controller chip with similar capabilities to the MCP73871.

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Re: USB, DC & Solar Lipoly Charger

by ko4nrbs on Thu Apr 28, 2016 11:30 am

adafruit_support_bill wrote:Charging a 3.6v cell would require a different charge controller chip. The MCP73871 can only be configured for cells as low as 4.1v. But I will mention it to the design team. There may be a LiFePO4 charge controller chip with similar capabilities to the MCP73871.

Having the ability to charge both Li-ion and LiFePO4 cells would be ideal. LiFePO4 cells are becoming more available and are not as prone to damage during charging and discharging etc. as Li-ion cells.

Thank you,
Bill

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Re: USB, DC & Solar Lipoly Charger

by ctgreybeard on Sun Jul 24, 2016 1:14 pm

Any progress on a charging circuit for the 26650's? I just discovered these and they look very interesting. Because they (and the 18650's) are used for vapes they are getting easy to find.

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Re: USB, DC & Solar Lipoly Charger

by adafruit_support_bill on Sun Jul 24, 2016 2:04 pm

No current plans for chargers for alternate chemistries. Our current range of chargers do work with the 18650 LiPo cells and packs that we have in the store:
https://www.adafruit.com/products/1781
https://www.adafruit.com/products/354
https://www.adafruit.com/products/353

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Re: USB, DC & Solar Lipoly Charger

by ctgreybeard on Sun Jul 24, 2016 2:25 pm

Thanks. One of those might work for me or I am also looking at the MCP73223 which can do 7.2V LiFePO.

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