She’s so cute!! Balanced, fused, and wrapped
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You didnt use sergical tools before while building a battery?
What a n00b get out of here
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Haha, I think most recently has been me. I found their use thru Dr. Mike tho.
To call them sergical tools is a bit much.
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Cheers for the hot tip! I love it!
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@b264 add this to your repository.
UL 3135 aka Stranded Silicone Hobby Wire spec
The Chinese part is obviously the ampacity
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builders,
I’m contemplating building a pack with Moilcel P42A cells, started to work up a BOM to assemble parts etc. and went to check on nickel amperage limits… holy faak …
at 45 amps each cell what are you guys using to assemble the P-packs?
Given that .3mm thick nickel is problematic with a K-weld… I realize I’ll have to build in a heavy buss bar-ish for the series packs but I can’t wrap my head around how thick (many) nickle strips I’m going to have to weld on for 45amps…
suggestions please…
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These are a guide only… i believe you can very safely add at least 50% onto those values without an issue.
Remember that most ratings are for that current over a 1m length of material. As our material length is a lot shorter than that, we can safely get a little more out of it.
Also, just because your cell is rated at 45a, doesn’t mean thats how much you are going to be pulling from it continuously.
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Understood… mostly it’ll be a cruise mode fun board… but I do plan on stoplight to stoplight drag racing… pulling as many amps as she’ll take for 5-10-15 seconds…
what is your suggestion for P-pack nickle strips?
3x .2 x 10mm strips?
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The strips across the p groups don’t necessarily (and very rarely) need to carry the entire series current…
Gimme 5 mins, i’ll draw you a picture
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Lets assume you have a 5p pack. Each cell is pushing 10a each.
The current only wants to get through to the next p group in a discharge situation, so depending on your series connection configuration, will determine how much current the p group strip sees.
In the configuration above, there are only 2 series connections. That means those 2 connections are trying to pass the whole 50a to the next group.
The p group strip only needs to deliver the current from the closest cells to the series strips. You can see that the strip either side of the center cell is doing less work, as it can deliver half its current to each side.
comprende amigo?
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while you were drawing your pik I was drawing one as well…
at 12S2P i’m going to have a 90amp pack 45amps possible to the series buss…
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In a 2p group life gets a little simpler 
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and yet my question remains…
given this construction what are your welded nickle strip recommendations…?
Your suggestion relies on those 3 pieces of nickel being a solid unit. In reality, you are only going to have a stable connection to the top layer of nickel
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I would join the 2 cells with one strip, and then give each cell two tabs. The tabs should come away from each cell not directly on top of each other, but slightly separated so that the solder from your series connection can be in contact with all 4 tabs
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