Curious why 20s6p and not 18s7p like Skyart (also nice postcount at 21700 haha)
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Top speed, I imagine.
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Why though? 
Itâs the same construction method that pure nickel builds utilise.
Also thanks!
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Steel has a quarter of the conductivity of nickel, the copper coating is wafer thin so it doesnât actually conduct anything, it just makes it easy to solder to
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Where did you get copper coating from? I think youâd use solid copper for this. The steel is just there to get the copper hot enough for welding.
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I thought thatâs what we were talking about? If itâs pure copper it should be fine but it corrodes so it will look gross and it work hardens more than nickel
Pure steel is a bitch to solder to
Wouldnât it just corrode if it got wet? Iâve seen many professionally made battery packs which have laser welded copper connections.
Itâs nickel plated steel though. Also I think soldering to it wouldnât be necessary, as youâd only weld on small taps to get the welds to stick. Soldering would be on the pure copper.
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Yeah it would likely corrode in time but iâm not sure if it would even matter as itâs only purpose is to allow the weld to take place.
I think there is definitely space for copper in esk8, especially if it has a noticeable performance advantage.
I think most wonât need it, but I feel that high performance boards could definitely benefit.
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In the vast majority of cases, itâs unlikely to be the case.
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Sure, but iâd like to see/do the science
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Probably it will corrode regardless, although I donât skate in the wet anyway. These packs last a few years max so again, time will tell.
There seems to be some confusion between the âcoatingâ (solder points) and the steel weld points. For the series connections and balance wires, solder was rubbed with a rag along the top. Used a small paint brush for the flux, 100W iron with a fat arse tip. Drag the solder along and quickly swipe across with a rag. Hereâs a not so good example, it was my first one so the solder is quite thick. You can get it super thin, looks painted on:
As for the merits of doing this at all. Iâll leave it up to people in here more knowledgeable than I to haggle over that one. âJust because you can, doesnât mean you shouldâ, perhaps applies. I just like the idea, no science - other than some vague notion this pack will make me feel way faster than I am, and maybe run cooler on hills. Kinda like racing stripes on a car 
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IMO, for solid series connections like brick packs, it could definitely have an advantage due to higher conductivity, but if youâre using the strap or ladder style things or whatever the difference between solid nickel vs that is probably negligible or goes back in nickelâs favor due to having a lot more cross-section.
For factories turning out large volume, it probably makes sense, assuming the process doesnât add much cost, because you can use less of a cheaper material for the same effective resistance. For custom builds I wouldnât consider the cost part a big deal unless nickel skyrockets, which I guess is possible.
Edit: Actually I guess if youâre folding over tabs the current has to travel through that part of the copper or nickel anyway so that all more or less applies to any type of pack. Iâm to lazy to figure out the effective resistance for the strap style copper vs solid nickel, but it shouldnât be that hard.
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Yeah I had the same thought. I did run the numbers at some point. Found a formula for sheet copper amp rating given a cross sectional area. It came out above my theoretical continuous draw target for the P42Ax4 groups.
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Theres no issue with that longer wire leading into the power cable? Initially, I questioned why it wasnât wired the way @jaykup described, i thought it was for the negative lead wire to be shorter.
Saw this post too late and ended up making it all work today; a nightmare but its done and looking pretty, just finishing off the bms.
How do i wire up the 2nd harness of this 18s bms
Got the first harness wired(right side), and got 8 packs remaining to wire the bms to.
My question is do i start off the remaining packs with the bms black wire? are all these wires just considered white or does the red/white matter?
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You can get solid copper sheet as well, thats what i would use. Those ladder strips have no place in esk8 IMO
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Just keep going in sequence dude, the red/black on the harness is probably just how they come to indicate which way around they go
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The main reason I didnât end up using sheet is because I wanted it slotted, more than I wanted it solid. Probably was worth a shot without the slots though, Iâve read some having trouble without them.
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I think in your case itâs fine cos copper = gooder. But given the option iâd go with the sheet
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normal to get a negative voltage reading when probing the 2nd harness? first one doesnât read negative
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