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Picking the battery to complete my drivetrain. Help me check my work

1559 Views 20 Replies 5 Participants Last post by  Chewy

I have currently bought:
Nissan Leaf Gen 2 Motor / Inverter
Zombieverter VCU
Tesla PCS and Control Board (10kw Ac charging and dc-dc converter)

Now I am to pick the most expensive part, and I am quite afraid to do so.
I have seen a good deal on a Tesla Model 3 Standard Range battery pack.
It was taken out of a car with only 5,500 miles on it and the price is $4,850.00 + $500 shipping.
I would plan to combine it with an Orion BMS.

Problem is, I don't understand how much capacity it has or how many volts it is, as it is intended to be a replacement for another Tesla.
If I look up the specs of that car, I should expect 50 Kwh with a nominal of 350v but if the cells are 5.2kwh, then It contains 9.5 cells??

Would this be a bad buy? I just would like a second opinion before I make a $5000 mistake.

The battery pack in question

Thank you very much for your time.
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That modules appears to be sold out, there are others but they are more expensive. The model 3 modules are too long and too high voltage for my large ATV application (48V), does anyone know if they can be broken down I to individual cell groups? Also, anyone know when Tesla model 3 switched to 4680, and was it only high performance/range model? Any of these in the wild yet? (Junkyard)
HA! I’m very risk averse as this is my first DIY BEV project so want to start simple. I’ll start a new thread for it when I have a few more posts.
I didn't post when I had come to a decision but it is probably helpful. I decided not to use a model 3 pack because they do break down, but into cells that are really long.
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There is a way to fit them into smaller cars, but it is difficult. The person I saw do that on youtube was named Superfastmatt and he got them to fit but it required a lot of metalworking skills that I do not yet have. I also had questions about how to hook up BMS, which again, is possible, but less straightforward.

Model X and Y have modules that are much easier to fit in your car and hook up with a BMS, but they are more expensive.
View attachment 136272

I ended up settling on Nissan leaf batteries. The ones I found were relatively low in price but still easy to use and fit in a car, and I figured I can always upgrade my battery to tesla modules later if I wanted more range.
I just came to the same decision about Tesla S cells. I don’t have the knowledge to implement open source software on BMS nor the cash for a multi-thousand dollar BMS (after the price of modules).
Do you mind relaying where you found the Nissan Leaf cells? They look to be more straightforward WRT implementing but the ones on eBay or Greentecauto are either 50-70% SoH or they want hundreds $ per module (making my 48V 200Ah requirement thousands). The nice thing with them is that they’re modular, I could build a 100Ah pack, and if it’s not enough (and as funds allow) turn it into a 200-300Ah pack.

I’m curious to know from people who have purchased used/remanufactured Leaf cells, are they holding fairly steady capacity or does the bottom dropout at some point?
It's funny how you went from a Tesla Model 3 module being too long, to a Model S being too expensive after BMS, then to a clapped-out Leaf battery being too expensive leading to halving the pack Ah which doubles the BMS cost per kWh and drops your vehicle performance to that of a golf cart.

This stuff costs money. Crazy money. Hobbies are defined as ways to pass time where the economics are insane.
Who is this directed to? I only ask as I’m the last poster but not the discussion starter. I can identify as I’m in the same boat as OP, Tesla Model 3 cells are ridiculously long and Model S cells ridiculously expensive…all of which might be OK if they’re weren’t all ridiculously complicated to implement with an extremely low probability of doing it correctly the first time and people new to the hobby don’t want to accumulate a $5k box of parts that are unusable because they either lost got discourage or realized they were in way over their head (at least I am).

This entire process has similarities to raising a child🤣, endlessly complicated with no instruction manual and a promise of zero money left at the end! Who’s in?!?
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Those used leaf modules are tempting to us newbies as we can dip a toe in with less chance of getting burned. That or prismatic cells whose quality can be questionable.

Occasionally the newer 112Ah Leaf modules come but them they are pricey. Pick your poison.
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