A123 LiFePO4 Cells - the iron man’s battery

This is a 12S LiFePO4 charger, 43.8V, with a GX16-3 plug

This is just a 10S li-ion charger that’s been tweaked/adjusted up to a 43.8V cutoff like @malJohann mentioned

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This is probably one of the biggest things I keep trying to sell myself on. Everyone says “the voltage drop is immediate but it flattens out so well that its super consistent until empty” - So its just a matter of do I care about the weight?

The answer is: not really. however my experience is with a 10s SPIM08HP so 6.1 lb pack. so do I really know what I’m talking about by saying I don’t care? Or should I fill a backpack full of cells and go for it? :smiley:

I will say using the backpack would make toting the board around the office much more enjoyable than having to make sure the bat-box doesnt come off the deck.

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Not all chargers are adjustable I invested heavily in 13p a few years ago building 3 x 13p batteries a few high amp 13p chargers. My focboxes ran cooler, I had more speed. Then then I killed a brand-new flipshite 6.6 single they were new on the market. Then a focbox. Then a motor. Went back to 12s opened up the cheaper 12s charger (4a) to wind it back to 50.3v no pots. Opened up the aluminium 8 amp charger no pots. Both must use a non volatile storage or a reference resistor to set the voltage. All my other chargers have pots.

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There are cases where the safety of the LiFePO4 is more important than the power density, and carrying the battery on you is probably one of those cases. Although, extra weight might also damage your back…
Back pain vs fire hazard… tough choices!

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LFP can most definitely go up to 3.65 per cell safely, but its not necessary unless you wanna squeeze evry last mah

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Do. It.

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FTFY.

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LiFePO4 charge at 3.65V/cell

However, near maximum range is achieved once you pass 3.45V/cell. From 3.45 to 3.65 has very, very, very little effect on range except it’s needed occasionally to turn on the cell balancers in your BMS.

Although unlike their li-ion brethren, they are a lot more resistant to overcharge and some reports even have them charging to 4.2V/cell without fires. However, that doesn’t buy you any capacity and just increases risk, so definitely don’t do that.

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I’ve heard this too. LFP is such a stable chemistry, I wish we could get higher capacity cells because its perfect for safety for esk8. LFP would make it many times harder to cause catastrophic failure from battery issues

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LiFePO4 excels in everything except “range per weight”.

If you need a long-range board, look elsewhere.

If you have a long range board, and need to complement it with a normal range board that is virtually indestructible and will be running long past when the li-ion batteries have shit the bed, then you need to try LiFePO4.

I have 3 LiFePO4 boards and love them. In fact, I just got home on The Blue One which is one of them. And yes, there was a charged li-ion board sitting right next to it. But I grabbed that one…

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I am testing some littokala LFP for my business too big for esk8 but perfect for other E vehicles. They are cheap and cheereful I am running a 24v pack of them though my inverter so far so good. At around $6au for a 7000mah (6200mah actual ) cell. I wish I could get more headways but these will work for my application.

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How many?

100 or so…

More than I have, only 20 or so.

Amperage? I’m interested

They are gold, my equipment has need in production 3 years now hundreds of cycles not much sign of degradation. I don’t think I will get the same life with littokala but who knows. The chemistry is solid. Too big for a board though.

Littokala claim 35 to 55 amps per cell I have pulled close to 15 amps with little sag so thats not bad. I always 1/2 littokala current claims. I wall looking at the 75amp 3.2 bricks but these work out much cheaper even with a Daly BMS.

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Just in case anyone wants these cells in a pre-built form, check our thread:

We will have about 100 batteries for sale. If you get 15wh per mile out of your drive train, easily can do 25 miles on a full charge.

They do take some time and care to take apart and also to assemble.

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Will you have any raw cells for sale, or will they all go into these packs?

Forgot to mention in the thread. Will add but yes, We are selling them for $3 per cell + shipping. Considering it takes me about 2 hours to disassemble them correctly and these cells sell for $6.55-$13.50 per cell new depending on the site, still a great price for these cells.

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