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Those voltages do not look right to me for LFP cells. Isnt the charge voltage generally 3.65, and nominal 3.20 per cell for LiFePO4?

And on your calculation you are dividing milliohms by a million - so your I^2 R calculation is off by 1000. Should be 12000watts at peak, and 2000 watts continuous. Even at 12000 watts, it will take a long time to heat up 1100lbs of batteries. Didnt old-school prismatic batteries like this generally just air-cool the packs?
 

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These are old-school? when I'm looking at batteries, what would i look for "new school"? :) Thx!
Well, 10 years ago this was basically the only way to get lithium cells for a conversion. Now, with as many production EVs as are out there, most people try and track down a pack from a wrecked car and repurpose it. That is what I did for my truck, with a tesla-made pack from a Mercedes. I think both routes have merit, honestly, and probably plenty of pitfalls. You are taking a risk with a pack from a crashed car, but honestly, you are also gambling that the prismatics are not a lesser battery grade being passed off as top quality (which you will need for a traction pack for a car). Plenty of debate each way. In general, you should be able to get a used EV pack for around 150$/kwh. New "Grade A" LFP prismatics that are shipping from a US warehouse are easily twice that. Once you add shipping and customs fees, I am not sure what your price point will be on these particular cells. I would do plenty of reading about making sure you were getting what you paid for.

Why would you think prices on quality LI batteries would be dropping?

Not going to happen...
Do an image search for "price per kwh for lithium batteries 2010 to present" and you will come up with a lot of graphs like this one:



The curve is starting to flatten out, but I suspect it will keep improving for a bit. I suspect the scale of production is going to grow by leaps and bounds, which should lend itself to economies of scale. I am curious what makes you think the price will stop dropping?
 
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