battery 6s3p wiring help

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#1

gents

trying to figure it out the wiring diagram for a flat 6s3p 21700 cell

look at the photo and tells me what is wrong please…

back 6s3p
back 6s3p1920×1440 222 KB

front 6s3p
front 6s3p1920×1440 220 KB

thanks

#2

Umm…rusted cells, maybe one or more that have vented, sharp slivers of nickel that could short a cell…and that’s just the stuff I can see.

I can’t get past all those problems to even consider how to weld up that pack.

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#3

That looks good from here as far as wiring . Why 6s? What’s the project?

On mobile so I didn’t see the rust that mooch pointed out - there isn’t any good way to use corroded cells safely afaik

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#4

From a layout standpoint, the connections are correct and you’ll have a 6s3p

From a battery builder’s standpoint those cells are :sparkles: S U S :sparkles:

Judging by the condition I assume you salvaged them from a water damaged battery, I’m guessing a waterlogged 10s2p and you lost a parallel group to the water?

For starters, if the pack has water damage there’s a chance water has gotten in the vent of the cells and there’s rust you can’t see, so at that point all the cells are potential ticking time bombs

But as I was once a broke college kid I understand trying to salvage stuff, if you insist on doing it here’s what I’d recommend

  1. check all the cells visually for any rust under the positive terminal, any that are rusted are toast
  2. check all the remaining cells for voltage, any cells that are significantly (maybe 0.2V?) lower voltage than average are also toast
  3. One at a time, carefully grind any burrs off the cell, cut the heat shrink (keep the plastic ring on the positive side, take great care to not touch the positive tab and negative edge with the knife, ceramic knife is preferred), sand off any surface rust, and re shrink wrap the cell using the plastic ring on the positive side again. If there’s more than surface rust that you can take off with like 600 grit then that cell is toast too
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#5

its for a foil, there are old cells for demo only

#6

I believe this set up is better

back 6s3p
back 6s3p1920×1440 292 KB

back 6s3p b
back 6s3p b1920×1440 164 KB

I will use 20mm triangle pure nickel .
will build 2 packs of 6s3p , intend to pull 90A out of them with molicell P42A

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#7

thanks for advise ,the cells are old just for demo

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