Might wanna point out that at 3amps it would take nearly 16 hours to charge this bad boy.
Luckily.i recently finished my below bench 20A charger <3
Upgradeable to 96v as well as and 50a with minimal effort. Just need a couple more server PSUs
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But it’ll probably take your legs several days of recovery after riding for that far
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Alright small update. Got my materials. Got everything siliconed properly. Had to redo it because the other silicon I used wasn’t clean and I wanted to to redo them.
Now they all look close to this.
I’m also pretty sure I know what my arrangement will be. I’m going to build it as a 12x7 upright but then folded at 6p. Then lay everything on its side . This way it’ll be harder to explain but it’ll hopefully make for a nicer shape on the deck will add pics as soon as silicon is dry.
The connections will be .15x10mm nickel for the p group (brine test in progress). Then using 1/2" tinned copper braid (9awg equivalent) for the s connections. Probably going to do 3 of these For each s connection. These will be soldered but I’m confident the large cells and p group count should provide enough mass to keep the actual temperature down and not damage each cell. Pretinning everything of course.
I will see if I can solder before welding but that might prove tricky.
The p groups will get one side of fish paper such that each group only has a single layer between them. This is mainly to save space. Maybe someone can tell me if this will be sufficient? @Skyart possibly?
Here’s a few more pictures for your enjoyment
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Nice build bro. I’ve got some nice 4 awg tinned silicone wire (the good, USA made shit) if you need some for this, probably overkill, but so is this pack. 
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Single layer of fishpaper should be enough. I would be more comfortable with each pgroup wrapped in fishpaper this would give you 2 layers of protection
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Thanks dude! Honestly the ampacity of this pack is only like 100cont 200 burst. Not exactly astronomical but the 3x 9awg should be sufficient. Thank you for your offer though!
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Hmm ok. Well I have enough fish paper to do either. I’ll see how dense I can get it with two Layers.
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Il send you some pics when I get home you can still get it pretty compact, if you wanna stagger those cells
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Maybe pics are not necessary lol. When you wrap the cell with fishpaper, make sure you push as much fishpaper as possible into the grove between the cells, this will let you get them closer together
This is the layout I’ll likely go with. Keeps the ground plane footprint small, opting for a taller stack. This is with one layer. Gonna let this stretch for a night and then add the second layer.
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Looks good homie
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[Also Brine test came back good after about 30 min]
https://www.amazon.com/Nickel-0-15x10mm-Battery-Welding-0-1510mm/dp/B07WBZQJYS.
Found a box as well
8" x 10" x 6" should fit this nicely
https://www.amazon.com/BUD-Industries-JBH-4959-KO-Knockout-Hinged/dp/B005UPA0DC
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Big update as the p groups are now welded.
With some tips from @pookybear I was able to dial in my welds quite nicely.
The pack on the left is where I started and the right is where I ended.
The bumps in the nickel are to allow some flex when compressing the pack. As the p groups are not perfectly straight.
I didn’t want the nickel to carry any stress. It’s not as pretty but it flexes nicely. And the shrink wrap will hide this misalignments and bumps
I sharpened my tips and made sure they were even,
This allowed me to reduce weld times from 28ms to 12ms.
This helped make smaller welds so I could get more in the same area. Also the grips didn’t get hot nearly as fast! Big big help as the heat used to really slow my welding down a ton. Probably shaved 2 hours off this battery that way.
Next is a connections with the braided copper.
If anyone has a link to some very large shrink wrap that would be greatly appreciated!
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You can prevent the P groups from bending and the nickel from bumping by form fitting your fish paper into each one of the valley’s between the cells and also by only wrapping every other group. If you don’t to a good job glueing/siliconeing the cells together fish paper can break them apart, happened to me before with some junk hot glue.
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Thanks for the input! Yeah I probably couldve done a slightly tighter job on the fish paper. But The bumps were put in on purpose.
I thought about only one layer between groups. But I’d prefer the extra insulation over the rather minor reduction in size.
Overall I’m content with it. I’m much happier with the second half than the first but hey that’s how learning happens.
Duck yeah 8x8x6 is standard junction box size and the perfect size for.the enclosure. Home depot stop tomorrow
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That is going to be such a mass in between your feet lol
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I’m used to it
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