Regen braking to stop? (similar to BMW i3)

[HyperMiler]

Would tend to agree with the brake proponent camp that regen should be under control of a separate deceleration pedal, because
- rolling without regen is my most favored and least expensive mode of locomotion I like to have as the default (no-pedal-touched) status
- dosage of regen / braking intensity should be continuous
- the reflex to stop by pushing the brake pedal should not be unlearned
- modern brake systems can anticipate your intention to brake hard by the speed of releasing and moving your foot, and will brake hard for you instantaneously
- ROW compatibility

 

[tonyx]

I just watched a Bolt test drive video which has a separate "gear" selection for 'regen to full stop.' I guess that is how they are handling those drivers that don't trust themselves to remember where the brake pedal is...

 

[HyperMiler]

Let's say a beginner learns to drive on an i3 then matures to a Model S or X.

Any guesses about (the speed of) their reflexes for emergency stopping a car?

Which will occur immediately when driving an ICE for the first time (as releasing the go pedal has no effect on reducing vehicular speed)?

Conceptually, I see advantages in separating go pedal from slow pedal.

 

[Jeff N]

I just watched a Bolt test drive video which has a separate "gear" selection for 'regen to full stop.' I guess that is how they are handling those drivers that don't trust themselves to remember where the brake pedal is...

GM gets it right by providing a dynamic driver option -- i3-style regen in 'B' or gliding with minimal regen in 'D' with the option of using a variable regen paddle on the steering wheel. It's trivial to toggle between 'B' and 'D' with the shifter. B is good in city and congested highway driving when you are frequently modulating vehicle speed whereas D is often better on the open highway.

 

[David99]

Let's say a beginner learns to drive on an i3 then matures to a Model S or X.

Any guesses about (the speed of) their reflexes for emergency stopping a car?

Which will occur immediately when driving an ICE for the first time (as releasing the go pedal has no effect on reducing vehicular speed)?

Conceptually, I see advantages in separating go pedal from slow pedal.

I know what you mean. It's a valid concern. In reality it's not an issue though. In both cars Regen slows you down, just the last few feet you switch to the brake on the Tesla when you go really slow and have plenty of time to switch. If someone is used to the i3 behavior, there are no big surprises. It's just the last little bit.

No EV has so much Regen that it it would slow the car down enough in an emergency situations. So the FedEx to hit the brake will always be trained no matter what.

 

[EV-lutioin]

Owning both the i3 and Model X, I can say without a doubt the Tesla has the better braking system. The i3 has a major issue with its regenerative braking. If you go over bumps or pot holes while the regenerative braking is active, it has a tendency to cut out and then need to ramp up again to full effect. This is a very unnerving feeling when you are expecting to come to a stop but all of a sudden the car begins to coast.

It is convenient that the i3's regenerative braking can bring the car all the way to a stop, but if you want the brake lights to stay on while you are stopped you have to quickly press and then hold the actual brake pedal. This can lead to some jerky transitions because the general reaction when applying the brakes at a full stop is to press down firmly, and if you do so before the car is fully stopped the reaction is abrupt. The nice thing about Model X is that even though you need to press the brake pedal to come to a complete stop, Auto Hold will then engage so you don't have to keep your foot on the pedal in order for the brake lights to remain lit. It also leads to a smooth transition between regenerative braking and friction brakes since you have to engage them sooner.

I am familiar with Hill Hold, but not Auto Hold. I am curious how you engage it? Hill hold will engage if you press and hold the brake on the MX when the front of the car is higher than the back, but as far as I know you can't engage HH on flat or downward sloping situations.

 

[Phil Seastrand]

I am familiar with Hill Hold, but not Auto Hold. I am curious how you engage it? Hill hold will engage if you press and hold the brake on the MX when the front of the car is higher than the back, but as far as I know you can't engage HH on flat or downward sloping situations.

All you need to do is press harder on the brake pedal and Hill Hold will engage. Then, pressing the brake again or pressing the accelerator will release it. I've never seen it engage automatically based upon the slope of the road.

 

[KaiserSoze]

I own both an X and an i3. While I prefer the i3 regen, switching between the two is not especially problematic. I do find myself occasionally rushing to apply the brake on the X, but this situation occurs rarely.

 

[Patomalo]

I would go for the regen to come to a complete stop too. Not sure why it doesn't but perhaps someone with more experience will tell us why.

For now I just apply the brake when the car gets down to 1 mph or so.

Does the brake lights come on as soon as you release the accelerator pedal?

 

[David99]

Does the brake lights come on as soon as you release the accelerator pedal?

It depends on the amount of deceleration. Full regen activates the brake lights. As regen fades out the brake lights turn off as well. The same is true at very high speeds. Even full regen doesn't provide much of a deceleration at speeds of 80 or above. The brake lights don't turn on when you let go of the 'gas' pedal at that speed. As the car slows down, the deceleration increases and the brake lights come on.

 

[Dean1944]

The i3 regenerative braking is especially useful driving down a long mountain descent. My tech. question is whether there are 4 wheel generators or one central gen.at the motor. This could be a big factor if one gets rusty or wears out. Thanks.

 

[MP3Mike]

The i3 regenerative braking is especially useful driving down a long mountain descent. My tech. question is whether there are 4 wheel generators or one central gen.at the motor. This could be a big factor if one gets rusty or wears out. Thanks.

The motor is the generator, there is nothing extra for regen.

 

[Rkilian]

The Nissan Leaf has a D for normal regen, a B for enhanced regeneration and a E pedal setting that is one pedal driving. For me the e pedal is too sensitive for normal driving; car immediately slows down hard if you let go of the “gas” but for traffic, parking lots and other city driving it’s amazing. Would welcome that in Tesla.

 

[mxnym]

The Nissan Leaf has a D for normal regen, a B for enhanced regeneration and a E pedal setting that is one pedal driving. For me the e pedal is too sensitive for normal driving; car immediately slows down hard if you let go of the “gas” but for traffic, parking lots and other city driving it’s amazing. Would welcome that in Tesla.

I think the setting would be neat, and I definitely wanted single-pedal driving when I got an electric car, but I also like that I have separate and almost complete control over brakes AND regen in my Tesla (I say almost complete because regen was obviously software limited sometime last year, so I can't regen as strong as I want as quickly as I want to anymore), so I've gotten over not having single-pedal driving and probably wouldn't use it (but I would welcome a setting to bring max [safe for the battery] regen back, and that setting could be on the same slider as this setting with the current behavior in the middle since max regen is one extreme [least consistent/comfortable, especially when you don't modulate your foot correctly, but most efficient plus you know when you're wasting pads and energy by using brakes] and brake-simulated consistent regen is another [most consistent and comfortable, but pads and energy are wasted to achieve that]).

 

[BBG523]

This has to be one of the best features in my Bolt EV over my MX. True one pedal driving and a Regen paddle on the steering wheel to help you add more regen/slow down the car to a stop. It's not a replacement for the brakes but it does come in handy and I use the brakes a lot less because of it. I find myself reaching for that paddle on my MX.