Outperformance metric is basically power density. The model described is some 13 kg and delivers 750 kW peak, 350+ kW sustained.
(That's 28 pounds, 1000 hp peak, 470+ hp sustained.)
The 40% improvement is actually 36% and is versus the previous model of the same company.
Peak power is a number that can be manipulated. You just dump short circuit current into a winding. Even if that peak lasts for 1 microsecond, you can "claim" eye-watering horsepower numbers.
I wonder if we defined peak as sustained peak over 100 milliseconds, or some more meaningful number, what that would do to the claims. You aren't really generating meaningful torque over 1 microsecond.
Surely they measure output not input?
I sort of wonder how well these things can be scaled down.
Wheel hub motors are obviously bad, for harshness reasons, but if you could have a motor like this weighing 1-2 kg, and put one on each wheel, that'd be okay.
Power-wise this would be okay if things are linear. 26 kW per wheel sustained power output is more than enough for a light car. The question is what torque a scaled-down machine can be expected to have.
I'm wondering if it would make sense to integrate the rim, motor and wheel bearing into a single assembly to save weight and cost. That combined with the weight and packaging benefits of not having half shafts and differentials might make it worth it. Plus there can be additional benefits, like the extra maneuverability that ZF Easy Turn and Hyundai's e-Corner have demonstrated.
30kW sustained/60 kW per wheel peak power is easily enough even for large passenger vehicles. Sustained could take 3 ton vehicle up a 10% grade at 120 km/h.
Things like that do exist though. There's an expensive Renault with motors like this, there's also the MW Motors Luka.
MW Motors eventually made a version where the electric motors were moved from the wheel hubs to a more conventional arrangement, so presumably they felt that it was some sort of problem, but they still make the original version and I've never been in one, so I can't be sure.
> That's 28 pounds
or about the same as a small dog
Thanks. Do you also happen to know the power density of the motors in the average EV car? Because the article uses "nr of Tesla Model 3" as a unit, which is meaningless without further details about it power density.
The power density doesn't really matter unless you want to put the motor in the wheel. You need to keep the unsprung mass low.
Basically all EVs have small and light motors compared to ICEs or compared to the battery. Shaving off ten pounds there is irrelevant.