which exact lifepo4 battery are you using?
A123 26650. I didnt know there were any others worth using
no, lifepo4 is full power until no power, so tread carefully if u r going on a midnight rush in the middle of nowhere
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True, I was worried about that, I read it stays at basically the same voltage until itâs basically empty. When I ride I am always looking back at my voltmeter, as Im sure most ppl do, to know how much longer I can ride. Will have to be more of a trial and error thing with Lifepo4. Good to hear about the minimal sag though. thanks frame
I currently have 12s lipo, just cheap 25-50c turnigy cells at 5ah and voltage sag is really annoying. After 6 miles of riding I have to ride conservatively otherwise the sag will dip into maybe not dangerous territory voltage wise, but close enough. Pack is 222 Wh so I should be able to get at least 10 miles
With LiFePO4, one of the big advantages is not feeling much sag. It will feel full until it just drops off and dies, for the most part. It will get saggy in like the last 5%, when itâs crazy close to dead. The sag will come in hard and strong and only at the very end. Thatâs about it.
Itâs not like [4.2V chemistries] li-ion where it starts getting a little mushy when the battery is still mostly full.
I accidentally overcharged a 43.8V 12S LiFePO4 to 51.1V by braking downhill on a full battery before I realized what I was doing. Two things meant that for the most part, nothing broke.
- was using LiFePO4
- was using 12S, not 14S, on a 60V controller
If either of those two things werenât true, then I would have probably had a battery fire or blown ESC⌠but since I built it conservatively, there were no problems.
lifepo4, like li-ion, sags in high current application but itâs not an issue as long as the the cut-off voltage is set correctly.
Depending on how much current you draw, lifepo4 can sag down to 2.8V or below per cell even though itâs still almost fully charged. Nothing to worry tho cuz thatâs still within the normal operating voltage of lifepo4.
Voltage is not a reliable measure of how much juice remains in a lifepo4 pack. Better install a coulometer ( https://www.aliexpress.com/item/1005001281009022.html?spm=a2g0o.productlist.0.0.603e5044Aj01QP&algo_pvid=95089cb3-7ced-4245-8174-e7543b91ecf7&algo_exp_id=95089cb3-7ced-4245-8174-e7543b91ecf7-11)
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wow thats really interesting, thanks. hmm coulometer. Is that a similar install to a voltmeter (solder to xt90 of battery).
On a side question⌠do you know how to order from aliexpress⌠I was just trying to order a 14s 51.1v lifepo4 charger on there and it said im not authorized to have the item in my cart or something. Cant find that type of charger anywhere, but i guess i could use a 50.4 li ion