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Comment by Valgrim | Hacker News Reader

It would seem more logical to me if the regenerative braking was tied to a physical user input. Like... the brake pedal from 0 to 30% could be regenerative, and beyond that engage the brake discs. Or it could be tied to the shift stick, on a L-D position, acting like a low gear on a manual car.

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I've only familiar with the Hyundai Ioniq and the Chevy Bolt, but both those cars can be configured for that - the Chevy Bolt you only have to ensure it is not in one-pedal driving, which is just a button near the shifter, and the Hyundai Ioniq you just have to set the regen to zero. It's a failure of the rental place that these electric vehicles are not set up in such a way to match the mental model of a usual driver

The Chevy Bolt has it's brake lights come on automatically regardless of what is causing the deceleration, and I believe Hyundai is coming out with an OTA fix for that as well.

When you drive the electric car every day, it's nice using the one-pedal mode... Except it has taught me a large flaw in that my instant braking reaction is to depress the regen paddle, which doesn't work (only 10kW of effort) when the car batteries are well below -20 C, causing me to panic and brake too hard using the traditional hydraulic brakes.

I find that one-pedal is okay as a driver and not so pleasant as a passenger: feet are really quite bad at applying constant pressure, so there’s a tendency to alternate between excessive acceleration and deceleration. This can be nauseating, not to mention a bit inefficient. It’s made worse by the generally fast torque response in an EV.

I’d rather see really nice haptic controls, like so:

One-pedal: the pedal has a detent at the neutral point, so a range of forces will hold it at neutral, and a small conscious effort will switch between acceleration and braking. (For good measure, neutral could be zero acceleration instead of zero torque or power.) This would require some kind of variable electrically controlled haptics, and it would need to fail safe.

Two-pedal: a similar detent, but on the brake pedal at the position where mechanical braking starts.

Either one would need serious driver testing, especially to make sure that drivers won’t fail to apply adequate braking in an emergency.

There's a whole bunch of legislation that specifies what happens when you touch the brake pedal and how much deceleration needs to happen at every part of the input range. Any system involved in that needs to meet much stricter requirements. This also applies to regenerative braking on the accelerator pedal if the deceleration is over certain values. From what I understand manufacturers will actually have multiple "regeneration" modes to work around all this, but I don't have first hand knowledge of this particular area.

Almost all brands of electric cars (BEV, HEV, PHEV) use regenerative braking when you press the brake pedal when possible (i.e. they switch to the physical brake pads when the speed gets too low for effective regenerative braking, or when the battery is already full, or in case something's wrong with the electrical system).

Big exception is Tesla: Tesla's braking pedal uses only the physical brake pads. In a Tesla the only way to regenerate brake energy is by lifting the accelerator.

Source: https://onefiniteplanet.org/wp/one-pedal-driving-and-regen-b...

But in a stick shift, the engine brakes, even in the highest gear ie 5th or 6th - the car slows on it's own about 3x quicker than an automatic in overdrive.

Yeah, that's how my car does it (unless you "shift" into coasting with the paddle shifters. It does feel a bit clunky when you change between regen levels since the throttle is mapped differently

My volvo xc60 does that.

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