Pros & cons: 10s4p vs 12s3p

i’d go with the 10s4p is range is more important, you’ll get about 10% more watthours.

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but i prefer 12s performance, all my boards are 12s. i find with a 10s, performance is pretty lacking at end of charge. with a 12s it’s super strong until lower voltage cutoff.

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More volts!! Pro.

Go with 10S for sure if you’re using VESC controllers

Why is that?

Okay thanks. I was wondering about that

Because the parts used in the vesc circuit shouldn’t be run that high, especially with a reactive load like motor windings. I’m not trying to run my controller on the razor edge of what’s possible because it increases failure rate. I’d prefer if the board failing on me was kept to an extreme minimum, especially if it means I lose brakes and definitely if it means a $150+ part is the thing failing

Lots of people run at 12S but I also hear of lots of failures. To me, not failing is a very important metric and thus I can’t consider it. Most consumer electronics are designed with a 40% margin at least, the components in the VESC being rated at 60V and 63V means 8S would meet that criteria, so 10S is already over the normal. 12S is too close

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What about running 12S with fairly conservative VESC settings? Is it necessarily a voltage issue or an amperage issue? Genuinely curious?

Higher voltage = lower current (amperage)

most of the components on the vesc are limited to 60v, but we need to leave some headroom. the components weren’t meant to be pushed to the extent that 12s pushes them.

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The voltage limits are hard limits; can never exceed and each individual part has some variance in manufacturing tolerance, so just because one works up to voltage X doesn’t mean another will work to voltage X

The current limits are not hard limits at all, and are only limited by heat … so the parts can’t get too hot. If, for example, you were to cool the unit more agressively, or tune it down in software, you could adjust current performance. But not voltage maximums.

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When you say vesc, are you referring to both the focbox and the vesc 6?

this is not a thing. can people please stop saying this.

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wait what? please explain.

higher voltage does NOT equal lower current. in most normal applications higher voltage actually equals higher current. its ohms law V=I*R so what no one ever mentions is R! you actually need to change the load in order to get lower currents from higher voltages.

so what you should be saying is: similar torque can be had from a higher voltage with lower current if you use a lower kV motor.

however with the same motor and un governed torque you will always draw more current with more voltage.

this “higher voltage = lower current” thing is missing half the equation and its pretty misleading to the noobs.

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ahh yea ok. sorry. should be more clear next time

so this is right? higher voltage + lower kV motor = lower current?

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yeah. don’t worry. its not just you… I see that +V = -I thrown around on this forum daily.

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I feel this is a bit of a misinterpretation of Ohm’s Law and might be confusing to some. The relation is V=I*R, which is the voltage drop across a resistor. So yes, for a constant R, higher current equates to a higher voltage drop

But what we really care about is power. Power gets things done; resistance does not.

The important equation for our purposes is: P=V*I

Simply put, less current is required at a higher voltage to achieve the same electrical power power output:

  • 2000W / 37.0V = 54A @10s
  • 2000W / 44.4V = 45A @12s

But really… higher voltages just give you the ability to produce more power. 12S can produce 20% more power than 10S at the same current. Using the same example, 54A on 12S produces 2400W


Back to the topic at hand: 10s4p vs 12s3p

10s4p will have better range and less voltage sag than 12s3p. Because at the end of the day you have 4 more cells and about 10% more watt-hours, as others have said

Example: At 2000W, 10s4p would draw 13.5A/cell, while 12s3p would draw 15A/cell

So the current draw per cell is actually less on 10s4p than 12s3p, which means slightly less voltage sag. And it has higher capacity (higher watt-hours), which means slightly better range.

If you wanted a fair comparison, assume both battery configurations are limited to 15A/cell. In that case, the 10s4p battery can produce 2222W, while the 12s3p battery can only do 2000W. So the power difference between the 10s and 12s (from above) is actually offset in this case, since you are really comparing 40 batteries to 36


Long story short, 12S can produce more power than 10S for the same [total] current. But a 10s3p battery can produce more power than 12s4p for the same per-cell current

Overall the difference is not worth stressing about… go ride your skateboard :slightly_smiling_face:


TL;DR: More batteries = More better

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I think what @GrecoMan meant was that for the same watt output at higher voltage the current has to be less than current at a lower voltage 12v * 10a=120w 10v * 12a=120w So however many watts you draw at a higher voltage it’s lower amps than lower voltage

We should all start over and call this thread “Pros & cons: 10S6P vs 12S5P” so the number of cells is the same. Because I think that’s more in-line with the OP’s intent. More cells is always moar better. But for the above, I’d use 10S6P

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This is why I went with 10s for vesc/focbox the erpm limit can easily be surpassed using 12s which would fry your shit. Also even being too close to the erpm limit can be bad as people have reported malfunction under 60 000rpm as well so it’s important to leave headway as I believe it was @GrecoMan said.

what about the vesc 6?

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