LHB - what is he even doing now

The enclosure is still only 11 18650s wide and two 18650s tall. I just tried triple stacking, didn’t work. So looks like 12S11P is the max if only using the three battery sections and leaving breathing room for big ESCs. Of course if you run lower current and use smaller ESCs you could theoretically put a layer of 18650s under them in the fourth compartment… but we’re getting into series/parrallel and balance wiring nightmare territory. But if you did that, i’m pretty sure a set of trampa or TB ESCs or anything smaller would fit on top of them. The air space would be reduced, but probably still plenty left.

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… so 14S11P would be a better fit actually because the groups would be 11 wide and no nightmare wiring.

Ok somebody do that.

EDIT: 14s8p 21700 pack would also fit with that method.

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Just need a thicc boi gasket :rofl: but yea probably a no go. I’ll be working on a 12s7p Tesla model 3 cells

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LOL that’s exactly what i just did with somebody’s evolve pgroups. I just threw them all in there to see.

double gasket to keep living dangerously lol

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Thanks for your time and advice amigo.
I’m eager to go for the 2S fold to save some space in the middle series connections.
I’m guesstimating your copper braid is about 1 cm wide. How thick is the nickel you work with?
I was pretty confident on materials until I saw the nickel / current chart on here somewhere. Which made me doubt the fold and use a 12 awg instead. I would be targetting 80/100 amps.

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Yeah, thanks Brian, that’s the chart I was referring to. But it’s basically telling me folding the nickel is a no go and 12/10 awg instead is recommended, while LHB seems to have confidence in a fold for 2S packs.

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Folding nickel all but eliminates current bottlenecks because of how ridiculously wide the nickel is at the fold.

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So I think I’m misinterpreting the amp ratings. as these would be the limit per S pack and not the total pack?

The limit is per conductor cross-section.

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Also, you’re not pulling current across a single piece of nickel. You would be pulling it across three or four pieces of nickel. very short pieces of nickel where the actual distance between the cells (or between the welds) is barely over a centimeter.

The real danger in folded nickel is using it in places where the pack needs to flex and twist. If used incorrectly it will tear, the best result of which is an unbalanced pack and the worst result would be sharp nickel tearing into cell insulation and shorting and causing a fire. There are only two occasions when i fold nickel instead of jumping it with wire or copper:

  1. in evolve packs where there’s no room for jumpers and the fold isn’t being stressed by deck flex because of its orientation, which is side to side and not front to back.

  2. on rare occasion in sectional packs like this where the flex is being dealt with by an enclosure designed to keep some parts rigid and some parts flexible so the individual blocks of the pack aren’t stressed by flex and twist, and the height or width of the enclosure won’t allow wire for copper braid (very rare considering the braid is only 2mm thick)

If you have room for braid or wire jumpers, you should use them as a rule.

Also its very, very rare i set my ESCs for more than 60 amps battery draw.

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Ok thanks man, so you’re confident with these connections your battery is rated for around 120 amps (2x 60a esc) and most of these will be peaks, the average continuous will probably be lower.
It’s not like I do not know what I’m doing. I just want to make sure I don’t need to beef the connections up for good reliability.

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Like i said, if you have physical space to do so, do it. Also welding series connections can make it harder to get the balance leads right. So if you have the space, use wire or copper jumpers.

what cell layoff are you doing with the proto?

12S4P Molicel P42A, two of the p groups are split across four compartments so i can get 10 cells across four compartments and 8 cells across the fifth.

Should be fun. Plenty of room for the wiring though, Lacroix made sure of that. The challenge will be making it nice and neat.

most people go with 12s5p, but i know it’s a tight fit. Just wanted to see what others are doing before doing it to mine.

This is the 10S6P 30Q variant of the prototipo. I don’t see how there’s room for 60 21700 cells in here unless they are ditching the mounting plate for the ESCs and eswitch and just cramming things wherever they fit.

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Holy hell.

so where does all this stuff go? lol

If anyone here has done this upgrade, i’d love to see the component layout in the ESC compartment.

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@Chibatterysystems was lurking yesterday :call_me_hand::arrow_up:
Maybe he might have more pics

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