Looks like rings to me on positive cells.
True, but if you’re gonna solder to the cells (all three of my packs have been soldered), you might as well use some nice low-resistance (and more flexible!) copper braid, rather than nickel strip. As a bonus, it’s also easier to solder than nickel!
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I avoided copper braid as it tends to wick the solder away (like desoldering braid). I did make sure to rough up all the nickel and cells before soldering them, as well as using flux on both surfaces.
The trick with copper braid is to tin both the cell and your spot on the braid, let everything cool, then quickly heat-and-smoosh everything together. With good technique and a good iron, I was able to do it in such a way that I could immediately hold my hand against the soldered joint. Bare minimum heat input at all stages, also keeps the solder from wicking.
Look again
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Those welds are looking pretty good bro, but possibly a little on the hot side.
It’s good to practice on the cells as different substrates may have slightly different characteristics.
I can’t view the video for some reason but you are aiming to get it just hot enough that the nickel won’t come off without tearing.
Too much heat not only transfers unnecessary heat to the cell, but it also puts a lot more strain on your lipo. It may even be possible that too much heat is detrimental to the nickel/weld as well 
Edit: also note that the positive end of the cells accept welds a little easier than the negative end. I usually try to do all my negative welds first, and then turn the power down just a touch to do all of the positive sides.
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So here I turned it down from 26ms to 20.
It was still hard to pull off. But on the side of the red lead not much in the way of artifacts left…
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nice. they look good from here 
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Make sure to sand the tips and round them uniformly
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Yes. Thanks. I plan on making them nicer on the actual go
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You want it to actually make a little hole in the nickel when you rip it off
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So I have glued and wrapped the p groups.
I have little tabs coming up off each individual cell. .2 x 8mm
I have wrapped the whole 3p group with fish paper.
I’m going to make the series connections next.
I’m going to to solder two pieces of 14awg silicone cable to strips of nickel. .2 x 10mm.
And then I’m going to weld the strips with the wire already connected to the little tabs sticking out.
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Nice plan Raf! Just make sure that when you weld the soldered strips to your tabs that you have something beneath the tabs like a bit of aluminium would be perfect.
Your welds won’t stick to the aluminium and it will stop the heat from your welds from damaging your insulation/cells.
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@glyphiks thanks for the zip tie tip! So simple, but so useful. No more wild nickel strips all over workshop.
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My plan there is to use a folded piece of fish paper under the tabs while soldering. 3 layer probably.
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For the folks State side. This seems like a good value on nickel strips with Amazon prime shipping. Had it in salt water and vinegar salt water for 24 hours and looks good .
10 meters .2mm x 10mm.
https://smile.amazon.com/Nickel-0-2x10mm-Battery-Welding-0-210mm/dp/B07W7YP8CP
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Cool bro, just don’t weld directly over the sides of the cells without an aluminium backing
@tinp123 makes it so much easier to unroll too
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I might have lost control a bit…
I need to figure out what to do with the silicone wire. So many gauges, and most vendors ship a hunk loose with no spool…
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I’ve always just made my silicone wire into logs with twist ties - that’s also how I used to ship it when I was whole-saleing. I’ve been able to tell AWG just by looking at it for a long ass time tho - at least for UL3135
If you can’t tell that easily, re-sealable bags with sharpie label helps, wire still in log form
If you don’t like that, DIY Spools out of PVC and cardboard or re-use 3D printer filament spools.
If for some reason you have miles of wire… Lowe’s has 1000m spooling reels for ~$7 ea. Can post some pics of mine haha
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