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Comment by tbrownaw | Hacker News Reader

> doesn't need neck-snapping acceleration

I thought this was mostly* a side-effect of electric motors inherently behaving differently than combustion motors.

* Not that it can't be deliberately turned off since everything goes through a computer.

Yes, pretty much. The torque curve also slopes down as rpm increases, so an EV with really weak low end torque will feel really bad on the highway.

Having said that, there are some that are fairly mediocre without being completely terrible. The FWD Equinox EV as well as the FWD EV9 are acceptable to some people, but also pretty slow cars.

There are two different factors here.

One, as you noted, is that electric motors can apply full torque from a stop, increasing perceived acceleration.

The other, and more impactful, is that electric motor power scales with cost much more cheaply than gas motors, so vehicles will oversize their electric motors.

There's a third factor. Ev's need to support fast charging. So they need to do support super high voltages and currents. That's much of the expense of a powerful EV. A powerful motor is relatively inexpensive in comparison.

If you can charge a car in 20 minutes, the battery and some other circuitry can support discharging in 20 minutes, which is an insane power level.

That's not exactly true. There is some shared wiring between the DC fast charger and the motors, but not so much that the powerful motors are "free". The wires that run between the motors and the battery are long.

I think the larger third factor is regenerative braking. That uses the exact same circuitry as powering the motors, and if you want to be able to brake quickly without the brake pads, that's a lot of kW to be absorbed.

Any way you cut it, I agree, it's an insane power level.

There's a reason I emphasized the battery in my comment. :)

Got it, I skimmed that part the first time I read it. We're on the same page :)

A powerful motor needs more copper between the battery and motor and more silicon in the inverter to handle the current. The motor is also heavier. This is all extra cost.

All that fast DC charging requires are cells capable of handling the current.

You don't get a powerful motor for free just because you can fast charge.

> are cells capable of handling the current.

Which is the most expensive part of an EV

My 2019 Hyundai Kona has a 150kw FWD motor. I love my car, but it's power is totally and utterly stupid. I can spin my wheels while going 60km/h and flooring it. It can be downright dangerous in the wet. Thank dog for traction control I need to drive it in 'eco' mode most of the time in order to make the ride feel sane.

I think a motor with half the output would still result in a great ride, but the car would've been cheaper/lighter.

Newer EV's come out with much smaller motors it seems, which makes sense to me.

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