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Is 2000W in <15kg possible?


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I wonder if 2000W motor in 10-15kg wheel is even technically possible? How much powerful motors weigh?

99% of my EUC rides are to commute 8 km one-way and I have no problems to charge after every ride. My V8's 480 Wh battery is more than enough, so in order to have as lightweight EUC as posible, I suppose I could downsize to 400 Wh or so. That should still be plenty enough to keep myself above 50% of battery (IIRC someone said that battery is used only for actual motor load, not the constant rated power). As far as I understand, batteries make up for quite some weight of EUCs.

So is something like 2000W, 400Wh, 16inch 2.5-3" wide tire possible in 12kg package, making it as super-safe city settler wheel in terms of wheel stability and power reserve for potholes, scrappy sidewalks, uphills, constant acceleration/braking?

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I'm not sure stronger motors are necessarily heavier.

What really limits weight/power is the batteries. You need enough cells in series to get to a high voltage. And you need enough parallel blocks of those cells-in-series to get high currents. Power = voltage * current, so both need to be high enough to drive a powerful motor, otherwise it's useless (and less efficient) to have such a motor.

So a powerful motor needs a big (physically, lots of cells) and therefore heavy battery.

Random example: 84V (20 cells ins series), 2 times in parallel, highest capacity cells (3500mAh) gives you a ~520Wh pack. Take 2900mAh cells instead, it's ~430Wh. 2200mAh cells give you a ~325Wh pack. (These batteries all weigh more or less the same, as the number of cells is identical. Around 1.8kg for 40 cells at 45g each.)
Max power for that is 84V * 10A (usually one serial configuration of cells can do 10A reliably) * 2 (parallel = multiplies current) = 1680W. So basically, a motor over 1500W nominal is pointless with such a "small" battery. To drive a more powerful motor, the battery needs to be bigger.

I guess this is part of the reason why the V10 has the same weight as the V10F, they use the same number of cells (just with different capacities) so the parallel configuration between the wheels is the same, instead of less parallel packs for the smaller capacity V10. (To be precise, power just depends on the number of cells = weight, about 4.2V max per cell * 10A * number of cells = your max power, for the above example 4.2V*10A*40cells = 1680W.)

As far as motor weight savings, they could make the motors from aluminium (some already do that I think, v10?) or Titanium instead of steel,  to save weight on the metal parts. I really don't know if you need more copper for stronger motors, or if it's just wired differently, or whatever the difference in build is.

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