definitely easier to build packs for sure.
12 cells to weld instead of 48.
100a continuous is plenty.
(i got this 100a number by extrapolating “6x power” on their power point)
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This got me thinking that there’d have to be a shift in welding, a single sheet of .15 nickel, no matter how wide, is not going to be enough. A stack of ~5x strips nickel just seems wrong somehow.
I don’t know what it’ll take for ultrasonics or laser to come down in price, but that seems like the next frontier once this level of power is available.
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Copper disks with wire soldered on?
Maybe we could we just use a bunch of copper wires like the Fuse Welder Prototype that @TinkerGear was working on.
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Copper for sure.
Side benefit: ultrasonics is great for copper.
Soldering copper onto nickel is what I figure I want to avoid, since that’s just shoving all the heat back into the cells that you got away from by welding in the first place.
What would be a good fusing current for these things anyways? ~500A? 
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Juts one crazy thing about the new cells that I haven’t seen talked explicitly anywhere, they managed to increase the energy density to 350 Wh/kg from around 250 Wh/kg
If you ignore the format change, 310 Wh/kg. That means if the rest of the changes trickle down to the 2170 cells, the range of our boards can increase 24% for the same pack size if you were already use the most energy dense cell (Samsung 50E and LG M50), more if less energy dense cells were used
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do you think any other cells will show up at a similar price/capacity to these tesla cells?
Not sure what they will go for post “sale” but even at say $3.5 they are fairly good.
I’m having a hard time not buying thousands worth.
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I have no idea. 
New cells are always being developed though. We have the 50E, 50E2, 50E3, M50A, 50G, and probably one or two others I’ve forgotten about. I don’t know anything about the “Model 3” cells yet though, just what I’ve read. Until I test them I can’t compare them to other cells.
My biggest concern is that we have absolutely no idea how well each Model 3 cell will perform. Each was salvaged and may or may not have been damaged in the process (or before). There might be different ways used to connect the top contact or different quality work done between the different resellers.
There are too many unknowns to be able to say definitively which cell might be best but I can certainly show how well the ones I will be testing performed.
Price is paramount for many but not for me. If I get the performance I am looking for then I’m not worried about price. Since the cells should last at least a couple of years any price differences don’t matter to me since I get to enjoy that performance every day for those couple of years.
But, I don’t buy large quantities of cells at once so I know it is easy for me to talk. 
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Ill send you 10 of these Tesla cells tomorrow for free for testing if you want. Just PM me a shipping address
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Right it’s just a 4.8Ah 21700 coming out of nowhere for $2.5 where similar cells are $5 is quite the wallop. I really want to see some other companies get to that stage.
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Thanks! I’m getting two sets of two from @Skyart but another set of two would help me see how consistently they perform across three vendors. I’ll PM you as soon as I figure out how to do that.
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Click his name, then message. It will link this thread automatically
That is assuming you were talking about this in the first place, if not, ignore me
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Thanks! Already sent, nice to see how easy it was.
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Since I know you from mostly vape cell testing, do you only purchase a couple vape cells? if that’s the case, a few bucks difference wont break the bank.
But some guys on here are building huge battery packs, and the savings can be quite significant
I’m thinking of making a model3 pack as a replacement for my bike’s 20s14p
I have enough space to fit a …20s18p 
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Read the last line of my post.
I buy up to about 50 cells quite often for cycle life testing, charger testing, etc. which is nothing like the quantities that you guys must deal with.
Each person can choose their own priorities. For me, it’s performance over price. I rather enjoy the extra performance every day for a couple of years. Even if the cost was hundreds of dollars more.
But that is just my own personal choice and in no way puts down someone who chooses price as their priority since, as you mentioned, they are buying a LOT of cells. In fact, I know I am in a very tiny minority.
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We care about performance.
However since we also care about capacity we end up using so many cells in parallel that in most situations the total output of the battery more than satisfies our requirements.
This is why you will see us using high performance cells in small batteries (2-3S) but lower performance in huge batteries where the sheer number of cells in parallel provides the current output we need.
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I noticed that pack config tradeoff being used by several people here. Makes perfect sense and is exactly what I would do.
Please don’t consider my statement about my personal preferences as being any kind of statement about what everyone else has as a preference. I do realize that there are a wide variety of riders with different preferences, all valid. I was only referring to myself and my own approach.
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Do you have the capability to safely open the cells? I’ve some places claiming that they don’t have a bunch of the safety features other cells have like a CID since they are made exclusively to be used in the car packs that implement that externally
If someone could also do a short circuit test would be cool
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Yes, I can safely open cells and do it often. You read my mind regarding the CID. I had also heard that it might be missing as it’s not really needed if you have good cell level monitoring and protection in the pack. I was going to do a teardown of one of the cells to look for a CID.
A short-circuit test I will not do though. 
As much fun as they can be to watch they tell you almost nothing about what it takes to force a cell into thermal runaway…soooo many variables. And I’m just tired of the cleanup and smell after doing destructive testing.
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Yes but think about the number of views on YouTube 
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