I meant the cables, but yeah. Should have said that in the beginning.
What cells are you working with? If 18650 12 awg will be more than sufficient. Even 21700 12 awg should still be ok in 4p.
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So I just took ot out for a test ride and it looks like it did the trick.
Is the ammount of sag considered acceptable? I am pulling a little over 80A total from the battery for about 10 seconds. I wish the status refreshed faster.
That could be very misleading, amp output of the cells is far more important than size.
Is sag like this normal for P42As?? I have VTC5As and mine donât sag even half as much.
This is why I asked what type if cells. Generally, 18650s will put out no more than 20 amps continous while 21700 may put out more than that. There are several factors of course. Hence, my leading question.
There is quite the difference between f.e. 50Es and P42As, so no, Iâm going to have to disagree.
A 7P pack using P42Aâs?
A charged P42A running at less than 12A (each) should only drop to about 3.8V-3.9V a bit after the start of the discharge. It shouldnât reach 3.4V until well past the half-charge point.
IMO you have huge amounts of sag, either real sag from every p-group or there is a voltage measurement issue that needs to be fixed.
P42s will, according to Mooch, only do 25 amps continous despite manufacturers guidelines. He recommends running them at 20 for better longevity. 12 awg will def do 80 amps continous. 50e in 4p config wouldnât be suitable for esk8.
Or the cells are fake.
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YupâŚthat could definitely cause a genuine sag issue!
Ik, the was just an example on how you cannot detemine wire gauge by cell size. F.e. I run 6P VTC5A, thats a potential 210A, no way 12AWG will hold up to that. But a 6P 50E configuration would be totally fine with that.
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I charge the cells to 4v each because I live in a hilly area.
This is the bms I am getting my readings from 12S 50.4V Li ion Smart Bluetooth BMS with 20A 30A 40A 60A constant current UART communication software PCB board|Battery Accessories| - AliExpress
The cells are from liion so I highly doubt they are fake.
Is there a way to upload logs from the robogotchi to this forum?
Yep I agree. If they were 30T for e.g. 12 awg might not be suitable either. Form factor def plays a role tho but the specs of the cell and also what youâre going to run ur pack at must also factor into your material choices.
Like just about any high performance round cell, the P42A can easily put out 100A for short periods. But that will damage the cell and lead to preposterous voltage sag. Thereâs a good chance of it going into thermal runaway too if someone keeps doing it.
I gave the P42A 30A continuous and 40A non-continuous ratings. This is what you can use to directly compare against the true continuous and non-continuous ratings of other cells.
My 25A recommendation was made to help ensure good efficiency, to help reduce risk, and to help increase overall cell life. Itâs not a do-or-die limit or hard rating of some type.
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That is what I was saying, Iâm glad we found some common ground.
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18650 but theyâre fairly high discharge cells, Iâm gonna go with 10 just to keep the option open to use it hard
That will definitely contribute to the early sag youâre seeing.
If there are any âchoke pointsâ for the current also there then it all adds up to a poor performing pack with loads of sag.
Test with a full charge (no downhill, of course) to see what effect your low charging voltage really has. That will tell you if the pack has any construction issues.
They are definitely genuine. 
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Wil you be running the pack above 80 amps? 12 awg will do close to 90 amps continous. Should still give you plenty of headroom but up to you.
Itâs important to consider continuous vs burst amperages. Thereâs very little chance, even running you pack hard, that youâd pull even 80 amps continous. In short bursts (e.g. hills) sure. 12 awg can do easily double that amperage for several seconds.