make sure you get better boxes. wouldn’t want you dismantling batteries too 
if i build my extrusion cage for my floatwheel, ill be needing some powerful cells 
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I’ll be taking that CAD model now,
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which part?
fusion btw
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yes.
Also what cells did you really want for that? is it not a paralleled battery to the stock one? Then I could see using some more powerful stuff.
No parallel on this
Loopkey to cut off the 12s1p and an xt90 for any 12s pack I feel like using
dmed you the file
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I can’t find where you mention how big your p-groups are but those 4800-5000mAh 18650’s are best at 5A-7A each or less due to their high internal resistance. Much higher than that and their run time gets much shorter due to the huge voltage sag.
40T’s and P42A’s are great at up to about 25A each. At above that I recommend the 30T for up to about 35A each.
I don’t know anything about that BH LFP cell but its higher capacity, versus 40T or P42A, doesn’t matter if its internal resistance is higher than those two other cells. The higher internal resistance would result in more sag and could even result in the BH cell running for a shorter amount of time than the 40T or P42A. Testing would need to be done to know for sure though.
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man they should have sent you some for testing!!
I am planning on making an upgraded Onewheel +/v1 16S1P lifepo4 and I a little torn between 5 and 6 Ah but the load can be a little high like 20+ A so I figure 5Ah is best.
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Yeah no the P group would depend on the Amp output per battery.
For p42a/40t does 20s10p sound reasonnable? 15A per cell continuous and 30A in hard pushes.
What if I went with 30q’s? Are they still worth it nowadays?
For 120A continuous a 5P pack using 40T or P42A would be okay. Your pulse spec though, IMO, means you should be up in the 8P or higher range and using just P42A’s. That could mean up to 200 cells in the pack,
You’ll be drawing 250A-300A bursts with a 20S pack? Even 120A continuous is up near 9kW of power.
For these current levels, forget the 30Q. If you want 18650 then consider the Samsung 20S.
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I’d be using a 10kw motor ( 8kw-20kw) so yeah the most Amps I can get the better
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Another round cell option for a high power pack is the Samsung 30T…35A continuous and 45A bursts. The least voltage sag for any 21mm diameter or smaller cell.
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Heres the CSV file for my 12s4p/6Ah BH32650 if you want to see how they hold up. They sag about 4-5v under 80A battery draw but they never warmed up so I can recommend them, although I would go with a 2p of 6Ah if you can for sag-reasons.
2020-11-27_12-46-39.csv (7.9 MB)
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Should/could I consider the non round cells? Prismatic,headway, pouch cells,etc?
You can consider using any cell you want. 
I don’t have any to recommend though and many cells out there have rather…umm…optimistic ratings. They’re just current levels that the cells can reach without immediately bursting rather than true ratings.
Check for reviews and YouTube testing videos for any cells you are considering buying. Always remember that any salvaged cells can be damaged internally in ways that will not show up if just a simple capacity test is done.
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I’ll defenitely do a bit more researches find the best battery for the buck too ofc lol
Yeah that happened ~100 samsung 20r 80 dead 20 working but they don’t keep their charge that good
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This I why I have trust issues.
An example why I always open my electronics from China before I plug them in.
This seems like a grounded wallplug but there are just 2 cables inside the cord. The GROUNDING OF THE METAL ENCLOSURE ISN’T THERE.
If something fails there could be 230V on the case…
I mean look at this shit
Anyway after calming down I put a proper cord with a grounding cable on there and screwed it to the aluminium case.
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I mean if there was no grounding plug on the cable how would they have grounded the enclosure
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Parametric Study of Spot Welding between Li-ion
Battery Cells and Sheet Metal Connectors
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Great find, thanks for posting! Definitely going to dive into this.
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