19S then. easy to do w/e @ 1P.
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Try the P42A then.
If it sags too much then lower your cell interconnect resistances and try the 30T.
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I made a parallel 15S pack that is split into 4S, 4S, 3S. So all I need to do is make another 4S and Iāll have 19S1P.
I need to order that damn JST crimper soooo bad.
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What does this mean? Or what does it implicate what one would do?
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Bigger conductors between p-groups or individual cells.
So in practice, wider nickel or more layers.
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Ahh okay, just wanted to make sure; Iām thinking of doing the same thing with a 1p pack. Thanks!
Add more metal to whatās connecting the cells and going outside the pack. 
Thicker and wider.
Use more spot welds (not in the center of the bottom!) too
Use larger battery leads.
Use shorter battery leads.
Make better soldered connections.
Safety first though! Never compromise that for an improvement in performance.
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Great to know 
So say I wanted to add an extra layer of nickel to a pack; would this automatically mean double the ampacity the connections would now carry? Or is there some tradeoff/dropoff as well?
Not here as in I should instead make more welds on the outer edges of where the nickel and cell meet? juuust wanna make sure Iām understanding right lol
Adding an extra layer would increase the ampacity of the strip sandwich but not double it. The welds have a resistance and that would rob a bit of performance. I donāt know if that means two 0.15mm thick strips = 0.29mm equivalent or something worse like 0.25mm.
A lot depends on the quality of your welds.
Just avoid the center 4mm or so. Go anywhere else. The center is where the tab inside the cell is spot-welded to the bottom and you do not want to zap that.
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What would be the consequences of doing that? Like, would it be an immediately obvious problem, or something that might be fine for 100miles and then suddenly fail catastrophically?
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Yes.
Either, at any time. Thereās no good data Iāve seen to quantify the risk and it would change based on the cell, weld power, etc.
It could just be a tab coming loose, doing nothing but bricking the cell, or it could lead to hotspotting that could lead to thermal runaway.
We have to avoid the venting ring on the bottom of a couple of cells too.
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Oh fuckā¦my standard style of welds is a : : : dead center in a 3mm by 6mm to 4mm by 8mm patch
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Are venting rings like the little ring notch on a S30q that goes around the cell a couple mm down from positive end?
Thanks for answering all my questions too
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No, just the bottom I was talking about.
The top venting disk is located underneath the top contact. The indented ring around the cell is made to hold up the top contact structure as the top of the can is crimped down onto the top plastic seal.
Hereās a bottom venting ringā¦
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this. so much this.
(itās fiiiine?)
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Yep same. Live and learn I guess 
Now my packs can be even safer. Thanks for the knowledge @Battery_Mooch!
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You could push out the center welds a bit, rounding out the pattern? It might be fine, it might be not. I donāt know. Hereās the warning for the VTC5A. Some other datasheets have this, many donāt. It might just be standard knowledge for the large pack assemblers to avoid the center or it might not be an issue for all cells. I donāt know so, for me, I just assume itās bad for all.
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I know the Sony cells have bottom venting and believe thereās a variant of MJ1 if not all of them that have bottom vent, is there a comprehensive list of ones that do?
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Iām not aware of one.
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