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by mikestew 1181 days ago
One other thing not mentioned - they brake faster.

No, they do not. Any car has brakes that can overcome its tires. All that is added by regenerative braking is the ability to lock the wheels more quickly.

Tires and weight (which EVs have a lot more of) are the larger factors in stopping distance.

2 comments

One thing I like about strong regenerative braking is how quickly it responds. If some kid darts out in front of me, there's a fraction of a second while I get my foot onto the brake pedal before the car starts to slow meaningfully. But with regenerative braking, the car is already slowing down significantly just by me lifting my foot. Just a little extra built-in margin, which is nice.
> No, they do not. Any car has brakes that can overcome its tires.

Well yeah, that's why we have ABS right?

But there's more to it than that... having a good way to engine brake (and in this case regen) keeps your brakes cool and prevents them from overheating. Regardless of stopping power in ideal conditions, overheated brakes are not safe.

Have you ever overheated your brakes? I’ve managed to do it twice. It took a $25 dollar set of brake pads about 8 laps on a race track. It takes multiple repeated hard stops of >~50mph delta to overheat even crappy bargain basement brakes on an economy car.

Brake discs on modern cars are vented and work like a centrifugal fan to cool them actively. They continually shed heat, so even dragging a brake pedal the entire way down a long mountain, as many drivers will do, is well within safety margins. So to overheat them, you have to get the heat in fast. Like 0-100-0-100-0-100-0 fast.

On the road, the only vehicles that experience brake fade are loaded trucks descending a grade, or suspects in a police pursuit.

Yeah i overheated my brakes doing exactly that, coming out of the Rockies
I don’t think overheating brakes is that common of a problem either outside of a sports car on a race track or a truck going down a mountain. The real advantage of regen brakes is way longer between pad changes and less accompanying dust.
… and the battery charge.