D140 or D823?
Yes in theory, but since youâre going to be running the cells right up against their maximum discharge rating, you should expect quite a bit of voltage droop. If youâve got the cells and the space, Iâd say go 4p just for that extra headroom. 30A total isnât really a lot, so youâre going to have a fairly low powered build compared to the people whoâve got 30Q cells and can pull 60A at 3p or 80A at 4p.
tldr it will work, but itâs not ideal.
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What gauge wire should I get for my series connections? Will 2x 12 do the trick? Itâs a 12s4p 21700.
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Been asking a lot of questions lately but hereâs another one: Iâm making a 12s4p flat pack but I didnât buy the ladder type nickel, only the single strips. The batteries will be end to end (pos to neg) and I figured a fold over would be perfect for this. Now that Iâve been warned away from foldover, how should I do these series connections?
I have seen where you fold the nickel to the sides of the cells, but that seems a bit much to with single nickel strips
It can be done. Itâs certainly easier to do with the extra wide (25mm) nickel so you only have to use a single piece on each end, but you can get the same result with thinner strips. Itâs just going to take about four times as many welds.
If youâve got the room for it, you might look into a set of busbar PCBs that you can attach your cells to, then solder your series connections to those. Something like these:
You can go back and look at some of @ZachTetraâs packs. He makes good use of the folded-nickel method.
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Yeah, the big nickel folded over definitely looks like the best way to do it. I donât know how crazy I am about making my own ladder style with single strips, seems like a ton of work and a lot of nickel to nickel welding. If thatâs the best way though I might have to
The big strips are so much nicer, it makes everything better. To assemble itâs less prep time for making the sections, less time for welds because less welds, and generally easier because there is just 1 big piece you can magnet down until you have the rack weldsâŚdoing 20 small pieces per series/parallel section is awful
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Also uh, if anyone is trying to charge their p pack I would not do it with these chargers:
Looking back it wouldâve made more sense to just buy a power supply and charge it at something more than less than an amp
10 hours in and itâs still not done (from 3.46)
Yup, like those.
Starting over. 12s4p. Ripped apart the other one. Blew the flipsky 4.12. Now got.another unity. Tje cells.on original test at 3.2 to 4.1. All off balance. Using these all test between 4.13 and 4.15. 80% 4.14
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Fresh from China.
Supposed 0.2 x 30mm.
Seems really stiff compared to some other 0.2 stuff I have.
In the salt it goesâŚ
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@whaddys Thanks to you bro, my battery can finally charge!
Its alive!
Now i shall wait for the heat tape and make this a 10s10p pack
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What happened?
The old bms got damaged during my rides and wouldnât charge the battrry anymore.
Hell yeah bro! Please clean up those wires tho they r giving me serious anxiety 
Organize them so they cross each other minimally, and if they do cross, put fishpaper between that spot. The reason is because the battery undergoes thousands of tiny vibrations every minute you ride, and those vibrations will cause the silicone around those wires to rub and eventually could wear through and cause the wires to short. You want to prevent that from happening ANYWHERE on your pack
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Of course Iâll make it look clean. I just need the heat tape. Gonna set it aside until then.
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I got a ton of 25mm * 0.2mm and 30mm * 0.2mm that just arrived, doing salt water test rn. HMU if you need any, Iâm redestributing by the decigram
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