Little bit more progress.
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Then I would assume the wrap is causing it. I notice a smell when removing wraps from brand new cells as well so I wouldnt be alarmed.
That glob, you can try and clean it up. Iād go @ it with a dremel and cutoff wheel and just grind it down. Also while making sure not to get into the cell rim. Some might frown on it but Iām aware of the risks. You do you though.
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As someone mentioned that looks like a spot weld that burned through to the metal. If that went through the metal can then DEFINITELY do not use that cell.
If it did go through there would definitely be a chemical odor but I donāt know if what you are smelling is the wrap or lube for the can drawing process or if it might be electrolyte from inside the cell.
As always, we can all make our own choice regarding the risks we take but any damage is unacceptable to the manufacturers so I am forced to recommend not using that cell, or any others, with damage.
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Thanks Mooch! Iāll be doing a more thorough look through these cells before I decide if they seem safe enough
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Where did you get those tesla cells from?
Hello everyone Is there anyway I can turn this 12s3p battery pack into a 12s5p using a parallel connector and a separate battery pack? Also if possible would I be able to get the bms to charge off both packs from one charger? Iām sure someone else has attempted to do this at one point or another.
No. No safe or reliable way to do this.
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Not really a worthwhile idea to pursue, more trouble than itās worth
Probably not in this prepackaged sense
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Its been so long since I used them I donāt think we were doing the 3mm thing on the 21700s, but does the same/a similar thing apply to 18650s negative side? Is there an internal spot weld I should avoid welding over? (Or is it so small that iād have to be welding in the exact center which wouldnāt make sense anyway?)
@Battery_Mooch or anyone else who knows 
I mean if you have room on your nickel might as well do a circle anyways yeah?
Thatās what I do, Iām not sure if itās necessary or not, however.
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On the cells in the middle of the P group I suppose a circle is better anyway, but on the edge ones I kinda end up with this weird flap which isnāt connected because im avoiding the center of the cells, I guess I was just wondering.
Also Iāve got like 5-6 packs to do so I am trying to be kind of efficient
Yes.
All Li-ion round cells have a spot weld on the inside of the bottom of the can. I donāt know if they are all in the center but it makes sense. The weld tip can only pass down through the center opening of the cellās spiral roll.
I would assume that itās at least a 3mm diameter spot for all cells, just to be sure.
Is there ANY way? Yes. Should you? Absolutely not.
What youāre asking is possible, but not only is it impractical, it is dangerous.
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lipo hookups. 2s3p (well actually 8s3p )
yellow blobs are xt90
left is fully paralleled.
right is 3 series pairs in parallel, but has less wires.
Thoughts?
does fully paralleled matter if the lipos will be charged individually?
is it worse?
It seems harder to build than necessary. What are you trying to fit this inside of?
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The molicel p42a 16s6p, a bms (13x66x128mm) and I wish the ubox could fit, but with just the cells and the bms is ok. Inside eboosted haero bro ds
Oh I have this sitting in my shop, Ill try to find you a better config.
But now that I know the enclosure type I think you did create a good layout. Are you planning on using a smart BMS?
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Yeah, daly smart bms with bluetooth, for charge only. Thanks a lot