At that point we should thinking about cells as decks!
120 cells wrapped in carbonfiber or somthing similar would result in a deck size like a good old jet spud 
And we´d safe money for an expensive deck 
Is there a particular reason to pick the positive end?
I’m considering a layout where half the modules are fused on the positive and the other half are fused on the negative end. This is just to make it easier to inspect burned out fuses.
I would fuse the positive end because it’s a physically smaller terminal, so if the fuse burnt, it’d be harder for anything to accidentally touch it and make a connection because the terminal didn’t encompass the entire body of the cell
But I don’t know
Also, the entire can of the 18650 besides the small anode is the cathode. So if the wrap were to break and short, fuses on the cathode would not be able to do its job. Therefore, my thinking would be to eliminate as many factors as possible and fuse the anode.
Do you still suggest using the 3D printer holders that you shared or is the fishpaper and silicone good enough?
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The fish paper has proven to be the better method. It is also makes the pack a bit thinner, always a plus if we can save some space!
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I think I am going to insulate my parallel groups with Kapton tape. Any advantage of fishpaper?
Kapton is good for heat insulation but doesn’t offer much abrasion resistance.
Also Kapton tape will store heat in the parallel group if you wrap a good amount around your cells.
Better to keep them nice and not to hot 
so on a 5P it sounds like the 20awg fuse wire is the way to go. regarding vibrational damage mitigation, @chaka are you recommending a sort of fuse tab, like a balance lead tab in fashion… for soldering the fuse wire to the cell or the bus bar? And what’s the exact length requirement there? it seems like there may be a way to put slack in the fuse itself to allow a minor amount of movement, but at the same time, a hot wire jiggling around may also lead to breakage.
mad solder skills doing it quick enough to not keep the cells hot too long. That’s part of the reason i weld, the heat is consistent and i can mitigate it easily with just pacing and pattern. If the first attempt of a solder doesn’t take it has to be reflowed. Of course a bad weld has to be rewelded as well.
i can’t imagine such a board would be pleasant to ride in any way at all. I shudder at the thought of another carbon fiber rattle box. but the range…
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Yes a tab on the positive end folded onto itself after making the welds. I then add another layer of fishpaper over the buss bars and fused tabs for insulation and to provide a small air gap before heat shrinking. I also make my series connections with a small section of 12awg silicon cable for strain relief. This allows the pack to conform to a boards curves without inducing stress on the connections.
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Just go to a hardware store pay 2$ more and be safe since they get their stuff from quality sellers
that is EXACTLY how i do the evolve packs. 12AWG jumpers between the twin P groups.
Since i use a trapezoidal stack pattern to cram more cells in less space in my own boards, i’m in the process of drawing up a nickel plate that would be laminated to fishpaper. The outside shape would have the same shape as the P group stack, with holes cut out where the cell ends go. The holes would be about the size of the area you would normally weld. Then i want to jump fuse wire from the plate to the cell through that hole. if i can also ice the cake with a sticky backing on the fish paper, it will drastically reduce pack construction time while increasing the safety factor.
So this would be a really short run and would likely require a thinner fuse wire, so i may need that chart posted earlier and a few iterations to get it right, but this is the direction we’re heading.
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Is fishpaper the same material as masking tape? Is kind of looks the same…
Ouch… I think I deserved that 
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That’s how we roll around here! All in good fun, welcome to the community!
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is a high dielectric really needed though? they get rated in the thousands of volts beyond what they would be exposed to in our use. id think something tough enough that it wouldnt possibly tear or wear through would be more important than a high dielectric number
You still need to mount your pack in a proper enclosure. If you think strapping cells to the bottom of the board with nothing but a pliable material protecting your cell is a good idea you are welcoming disaster.
i’m questioning if the dielectric strength is important or getting a material that is tough more important. Considering the voltages we use are so low I’d think the bigger worry is the material ripping and not a voltage possibly breaking through the material