Photon + LiFePO4 battery = easy?

General
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I’m looking to replace my LiPo (3.7v) batteries with safer LiFePO4 batteries (3.2v). I’m just wondering if it’s a straight replace? Would recharging be a problem when simply replacing the types of batteries? Would love to hear from people using LiFePO4 batteries or anyone with some advice to get me started.

I’m also looking at putting a Photon inside a cheap solar garden light, and replacing the LED with the VIN and GND. Anyone tried this? Just want to get something outside and powered without any interaction. I purchased one and it came with a good size panel and a 500mh LiFePO4 battery (3.2v) inside, so I thought it would be an easy to start project.

Thanks for your time.

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Just finished a big discussion about this stuff at Battery and Solar Panels for 12V motor controlled by Photon

I think the LiFePO4 batteries charge differently. http://www.powerstream.com/LLLF.htm

I know you can get LiFePO4 charge balance boards at https://www.amazon.com/Battery-Balance-Charging-LiFePO4-Lithium/dp/B01E3A0S04

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@gordi555 Using LiFePo4 batteries are not a direct replacement because they have a lower operating voltage range which will not meet the Photon’s 3.6v minimum input voltage requirement.

On the Electron they will not work either because the charging chip will overcharge the LiFePo4 batteries, and again the operating voltage is lower than required for proper operation of the Electron.

You would need a voltage converter to boost the voltage to an acceptable level & you would need a LiFePo4 charging chip to charge the battery to the proper voltage.

If only it was that easy :smile:

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Thanks for the detailed response @RWB was helpful!

@rocksetta yes it was your thread that I discovered the much improved LiFePo4 battery technology, I really enjoyed it! Thanks for sharing!

I’ll read up some more I think. Think I may just go down the route of a larger scale project with a solar LiFePo4 charger controller and a big LiFePo4 battery. Then run the boards from either a USB out or the load converted down with a smaller regulator.

I take it a swap from LiPo to Li-ion is easy as same voltage? Is Li-ion a bit safer than LiPo?

Thanks all!

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@gordi555, LiPo is the same as Li-On for all intents and purposes. I would go LiPo with batteries that have built-in (electronic) protection.

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@gordi555

Yes, switching from LiPo & Li-Ion is easier since they operate at the same voltage levels.

Here are some cells you can also work with that have double the cycle life span and the same voltage levels.

1 Like
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Thank you all, very helpful to a newbie like myself!

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Don’t totally give up on the LiFePO4. They should be much safer than the Li-polymer. The Li-polymer can have issues both when charging and when discharging. The LiFePO4 can output higher current than the Li-ion. They are lighter, recharge well and more eco-friendly.

I will try using a 5V step down regulator https://www.pololu.com/product/2831 with 2 or 4 LiFePO4 in series. That should be able to power the Photon and other devices. May be Mar 2017 before I have any results.