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ameliusyesterday at 9:43 AM3 repliesview on HN

But EVs are already heavy because of the battery. I suppose percentage-wise the motors don't make much of a difference (?)


Replies

nmehneryesterday at 10:12 AM

The issue with this type of motor is that it is part of the unsprung weight since it is inside the wheel. This is probably why savings here matter a lot more (or at least in a very different way) than the battery weight.

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DrScientistyesterday at 1:35 PM

It compounds. If you have a lighter more efficient motor you need a smaller battery for the same range, that combined weight loss means you meed lighter brakes etc etc, and because the car is now lighter you size of your motor you need is less.....

They claim, this compounding effect works out to basically double the effective weight saving from battery and motor.

ie if you start with saving 50kg on motor, and 50kg on battery, you end up saving 200kg over all. Still only about 10% of a typical electric car.

https://youtu.be/3qjB6GnhloY?si=yqlz7Evuyf5VaghO&t=446

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ponikoyesterday at 9:59 AM

Yea that's the thing right, the battery is so very much of the weight that optimizing the other parts are "meh" at this point. What is cool is that the 600Wh/kg solid state batteries seems like they are really finally here soon :) i.e removing 200-300kg from a car in one go will be a game changer.

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