Back to the drawing board. Need some pro advice

[skyblaster]

@b264

Now, if you test all the cells and one or two are weak (common with new old stock 30Q cells) then a 12S4P is a slam-dunk. Leave the weak cells out of the pack.

I don’t have a load tester, but I did check each cell with a voltmeter and they all measured between 3.38 and 3.40V. Purchased July 31st, 2018 from NKON.

@b264

That VESC 4.12 will do 12S in BLDC only mode (and FOC or BLDC at 10S) and no matter the mode or voltage, keep battery current under 25A.

Thanks so much for your feedback!

I’ll assume my battery builder can load test the cells, but otherwise I guess I’ll go for the 10S setup as originally planned. Knowing I can choose between FOC and BLDC without purchasing a new ESC is fantastic news.

I’ll go ahead and order a charge-only BMS tomorrow. Cheers!

[b264]

If they are all sitting new and purchased at the same time from nkon and are all measuring between 3.38 and 3.40V then I’d probably opt for the 10S5P

50 cells is more range than 48 cells

[b264]

Whatever you do, make sure you set your cutoffs properly or you can junk your battery.

I like these for 10S

@b264

10S li-ion; super-conservative (42.0V charge)
cutoff start 36V
cutoff end 34V

10S li-ion; conservative (42.0V charge)
cutoff start 35V
cutoff end 32V

10S li-ion; aggressive (42.0V charge)
cutoff start 32 - 33V
cutoff end 30V

10S li-ion; max-range (42.0V charge)
cutoff start 36V
cutoff end 30V

10S li-ion; range + conservative (42.0V charge) {my preferred}
cutoff start 36V
cutoff end 32V

but the whole thread is full of advice.

[Venom121212]

Too much resistance in motor. Feels not good

[b264]

Use a Mini Remote and adjust the center/idle position so it’s barely on light throttle. You can do this in real time while riding.

Also weight the throttle curves toward the ends and use low motor currents.

[Venom121212]

But then it’s constantly idling. A slow decay of acceleration is more what I’m after but that’s more discussion for the push assist thread