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by dotancohen 12 days ago
Reducing the motor mass by 200 kg means you've just removed 10% of the weight of the vehicle. You could theoretically now reduce the battery pack by 10% as well.
1 comments

Not true. The CdA (coefficient of drag multiplied by frontal area) matters far more for range than the weight for range. That is a smaller EV, which may very well be heavier can have a higher range and efficiency.
The Cd matters for highway driving, but weight is the dominating factor for city driving.
As efficiency improves across motors and inverters, wouldn't regen make CoD matter more, possibly tilting it to the dominant factor again?
Regen recoups about 80% of the kinetic energy, and it is already up close to the theoretical physical limit without switching to exotic materials.

Cd will never be the dominating factor at speeds which do not produce significant aerodynamic drag.

> Cd will never be the dominating factor at speeds which do not produce significant aerodynamic drag

That helped it sink in, thank you

Remember also that tires (deformation) and the like sap energy too
I don’t think there’s a whole lot of room for improvement there.