Found it!
You, sir, are a wealth of valuable information.
Clicking all the links now.
I by a lot from Pure Nickel from here: https://www.aliexpress.com/store/group/Nickel-Pure-Nickel/1758634_501015141.html?spm=2114.12010615.0.0.5b314950bNtJJ I have never been cheated with the plated stuff.
Much higher resistance, also it corrodes after some time just because finger oils and contaminants you expose it to during a build. Can burn out and cause a break in the circuit. Plated is really only good for making protection circuits on cells (5mm), you put a strip of Kapton tape on the bottom and top to seal it off…
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during a hard, deliberate short, yes. Like flash paper.
WRONG!
Extremely stupid pack design… I see this mistake made everywhere, build after build, here, ES, ElectricBike … So common.
"Much higher resistance: … Ampacity Chart:
High Temperature Silicone Wire: … Ampacity Chart:
Nickel Plated Steel corrosion on a NEW battery pack, still under warranty:
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Extremely stupid (Custom) triangle pack design…
How is anyone supposed to swap out 1 or 2 bad cells in the middle of the pack? By their very own admission “A special epoxy based glue, very strong, almost impossible to break apart”.
Soooo, butcher the pack apart, damage 20% of the cells, rip the shrinkwrap on others and have to do MORE butchering and repairs?! Flat packs and hot glue is easily separated with Methyl Hydrate and a Q-Tip, EPOXY…%#@!&! ass difficult!
I really cant believe the stupidity of these so called “Professionals” that everybody accepts as the authority on building. The worst part of this is, stupid follows stupid and perpetuates the same stupid mistake. As a consequence it becomes the ‘Norm’ and accepted as the standard…WTF? Does anybody actually think for themselves anymore? As a society have we become so dumbed down that some of us should voluntarily take ourselves out of the gene pool so the species can survive?!
Am I the only one that has thought this thru?, I know there is 1 other commercially available product, from only 1 source that I have ever discovered, specifically for this type of build. This, on the other hand is available EVERYWHERE…
YES, I build my custom packs with this method.
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You have valid points, but they make packs for production vehicles, failure means replacement not repair. “if 1 cell goes bad” isn’t a consideration for companies making packs with no intention of ever repairing.
I am loving the activity we have going on in this thread here, some of this discussion was apparently very well needed around here. Thanks for all the info @RootedSuperuser, @scepterr, @longhairedboy, @Vanarian,and @Jinra
@RootedSuperuserI actually have the same welder(709), and have to admit, the hand probes are all but useless(very weak welds). I did see those cardboard insulators(I never thought of using the coin rolls though, nice idea), and will definitely be using them on ALL future builds. http://esk8content.nyc3.digitaloceanspaces.com/uploads/db2454/optimized/3X/1/0/10636dc203ce66e00ff5dd93858ef775e8e38d68_1_690x360.jpg
@RootedSuperuser Can I ask what exactly is wrong with the pack design in this photo? Is it the layout that you think is bad, or just the fact that nothing is insulated? Also, would the steel in nickel plated steel stips be carbon steel, or the stainless steel?
I really wish I would have just purchased the adruino kit instead of the 709(https://malectrics.eu/). It seems so much for versatile, and not to mention it’s less money. I just wanted something I could plug in and have it work, but that was a mistake imo.
I agree with @longhairedboy 10000000 percent that using the machine mounted probes on the sunkko while trying to keep the cells aligned is like an acrobatics act. And, I also found it very difficult to source legit pure nickel strip.
All in all, there were SO MANY things that I learned along the way building my first two packs. I am currently in the process of making a custom pack for my Carbon GT board, and lets just say iv’e learned quite a few lessons. Biggest thing I learned? INSULATE EVERYTHING TWICE. I found out the hard way that my CGT deck actually conducts electricity fairly well(enough to short out my pack twice before I figured out what I was going on). Also, Those cardboard caps(https://goo.gl/EYwbyo) that go on top of the positive terminal are absolutely necessary if you are not using plastic spacers(ask me how i know).
tldr: use all the insulation you possibly can.
My personal tip for using the sunnko, bolt it down to the work surface, and use the pedal. This way you can put a LOT more pressure on the probe without killing yourself trying to hold it down, align and weld
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Figured that out real quick 
. I currently have a large rock on top of the welder until I get it strapped down properly.
After building a couple of packs, I can confidently say those circular cap rings for the positive end are super necessary to have a safe pack.
@RootedSuperuser have you tested yourself that those dime coin roll packs fit 18650’s without issue? If so where did you order? Don’t wanna order 1000 here and not have them fit(https://goo.gl/t651Ay)
If you have a “dollar” store near you they usually have bags of coin rolls
I actually do have a few local dollar stores around here. I’ll check it out, thanks man
To be fair, that pic is filled with mechanical bends which will obviously fracture, reducing the amount of material the power has to flow through, increasing resistance and melting the metal. This thing looks like it was hit by a car. If i saw a pack like that come across my bench its not time to repair it. It’s time to bin it with the rest of the cells for hazmat disposal.
This isn’t a case for using nickel, its a case for using better enclosures.
A case for using pure nickel would be cooler operation, higher discharge rates, and longer battery life. Not mechanical strength. Packs aren’t meant to be structural and if you expect them to be you have a lot of disappointment ahead.
Also easy on the bold caps. Your response made my initial draft replies a lot more vicious than usual. It’s too early to be editing myself with the expectation of a professional result.
That’s exactly what i do. Except without the pedal. At first i was doing the pedal but then i somehow managed to get the pressure right while just holding it and just pushing upwards. OR maybe i just got used to the manual acrobatics. I want a wand.
I’m modding my 788 with a wand soldered directly to the transformer inside , ill let you know how that goes 