Yup clear wrap. They are 21700 cells from a Tesla module.
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How are you reaching down to the positive contact for the connection? Spot-welded nickel strip or will this be a compression pack?
For those who don’t know this cell doesn’t have a standard top contact, it is recessed and has a fuse wire/strip welded to it. When you buy these cells they have had the fuse wire clipped off, standard top contact structures welded on, and wraps added.
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You cannot spot weld because the positive terminal is aluminum. The 3D print has a dimple which pushes a wire mesh into the terminal it’s kinda hard to see in these photos but it’s the best I have. They eventually get screwed together to keep the compression.
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Thanks for the photos!
Ahh….so Tesla’s fuse wire/strip connection is laser welded then?
Pardon the messy workshop 
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If it’s not messy then you’re not doing any work. 
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It was definitely a learning process removing and cleaning those cells but after trying a few different things I figured out how to do it pretty quickly. It had 396 cells on it and I’d say it would probably take me about 8 hours to remove and clean all the glue off all of them.
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Is there a risk of the braid pushing into the negative rim of the cell?
I suppose there is always that risk. I put a fish paper ring down and then wrapped over that.
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I’ll be using the same compression mechanism, tell me your feeling of it when you assemble it !
I already have this 10S2P pack completed and it is great as long as you have quality 3D prints you’ll be fine. I have 20 miles on that pack and I’m mailing it off to a client.
They are not the best performing cells in the world but I paid $1.25/cell for them so I can’t complain too much.
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Thirty-five 10S chargers and 15 boards later, this hits me so hard. And also 12S LiFePO4 charging to 42V.
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Nice. I did a external 10s pack a while back ago for longer range.
I’m able to go just over 40+ miles if I keep the Watts/miles reasonable with the pack onboard and the one I carry.
This is a 10S10P pack, but with 18650s. (Panasonic PF)
So I’d imagine with conservative settings on polyurethane you should be able to beat that. For reference I am 210lbs (96kg)
On my primary board I have a 10s7p 25 r (17.5ah) and I can get 30 miles on that. This 10S10P will be 43ah. Combined I should get close to 100mile range. That board is on 97mm Thanes.
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have you tried printing it sideways ? if it print well you could make even more at once
Nice,
I started something similar 2 years ago. But after assembling the first p-group I went for nese.
The original plan was to have 1S9P Stacks which are 3.7V * 3A * 9=99.9Wh, so just inside of most of the airport/airline limits (Lufthansa e.g. says: nothing over 160Wh, max 2x up to 160Wh, unlimited <100Wh).
Thats what i came up with:
Small PCB with XT60 (one for each pole, so up to 2x 60A for the pack), Pinheaders for the balancers with small fuse on the backside, small conical elevations, so the stacked groups “find” each other, epdm for compression, and a gasket on the + pole, so that the risk of shorts is minimized.
Over all it did work, but problem was the assembly + compression: The 3D prints are so flimsy that you need endless screws, and still the ends (where no screws are) bend upwards. Also I did not trust the meshed cable to stay in place and not short the cells on the + pole.
How are you keeping the compression?
How will connect the p-groups?
Edit:
If you wana have a look into it: https://a360.co/3iccGnf PW: giga
Full pack looks something like this (different versions mixed 
)
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