haha that’s what he is doing the tests for…
I was planning on making one 12S4P P42 and running that at ~160A
I can order some more and try to make a 8P also for MAX specs
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Just trying to get a sneak peek 
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Definitely do the 12s8p P42A and not tesla cells… I get 3V of sag on mine which a lot better than my old 15A rated cells that got 7V 
(That’s only around 120A too)
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already have them here, 200A isn’t a requirement just the highest I could go on the setup if I wanted to race or something.
I can’t quite afford a bioboards deck to go 12P… I guess I could tho
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Ok, so I’m a little confused about something.
I am talking with a potential customer about battery options for his build. I suggested these Model 3 cells as potential cost-saving option compared to the P42A (he wants a 12s12p, so the amp discharge capabilities are not as much of an issue). He asked a very good question, and I am not sure I remember seeing it asked or answered in this thread.
“How do we know these are legit?”
Uhhhh…? I dont know.
The story that we all heard when they hit the market was that Tesla discovered a bunch of battery packs that had defective BMS units or something, and so they sold the packs with all their brand-new, never-cycled cells off to recyclers. Those recyclers then welded on positive terminals (of several different styles), wrapped them (with somewhat inconsistent labeling), and sold them in bulk for stupidly low prices.
But what evidence do we have that this actually happened? I have searched around and have been unable to find any mention of any kind of sale such as this. I would assume that since a myriad of tech sites will climb over themselves to write an article about an employee bathroom being closed for cleaning at a Tesla factory, that a huge supply of brand new cells hitting the consumer market would be, if not front-page, at least news.
During my searching I came across this video here, which furthered my skepticism. These dudes had quite a time pulling these packs apart, and even once they got the individual cells apart, they were still covered in tons of adhesive and other crap. The disassembly here looks insanely labor intensive, and I cant imagine that the cells we have now came from a process like this and still managed to be so cheap.
So I decided to contact www.BigBattery.com, where I purchased a bunch of my Model 3 cells from. At first I just tried their in-browser instant messaging, and I got a response in minutes.
They asked me to contact their sales email, which I did, and I have heard nothing back. I will let you all know what I hear, if I hear anything.
So what do yall think? Am I overthinking this? Is there a key bit of evidence that I overlooked? If the cells do what they say on the tin, should I stop questioning a good thing? Should we start calling these “Panasonic 21700A” cells for the sake of accuracy (and in case these never came from any Tesla packs, but were rather just overstock purchased by resellers directly from the cell factory, as I am starting to suspect)?
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yay accuracy.
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Don’t they have the laser welding marks on the terminals?
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I posted this in the top a while ago, see it?
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Apparently not! Thanks for re-posting it. It’s baffling how they can sell the cells so cheaply with a process that labor and equipment intensive.
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Yo wtf I didn’t see this before either. That’s super cool. Especially the pneumatic glue removal and their huge testing bank
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Do u think these are legit then ?
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This video lowered my blood pressure thank you
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I’m about to buy 200 of these and have them shipped to me in Toronto Canada. Any suggestions? I was going to contact UPS to do the cross border since bigbattery is only US and since each cell is under 20Wh (3.5V storage x 5000mAh) and the total package is under 30kg I should only need a lithium ion battery label and a label saying don’t ship by air?
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Ground shipping with proper labeling should be fine, but I’m not an expert so dont listen to anything I say.
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im either going to build a 12s15p or 16s12p if I get a 16s bms. The 12p would give me more range than the 15p right? because its 196 cells vs 180 cells?
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In theory, yes. In practice, this has a lot to do with the efficiency of your drivetrain, motors, and motor controller at different voltages and speeds.
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How you ride it.
I think the one component that most people neglect to take into consideration when talking about system performance/efficiency, is the rider themselves.
They are a critical component that affects the performance of a build more than nearly any other component
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Just think of it like less overhead. You still gotta pay the bill or the lights get shut off…
i dont know what you mean lol
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