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General Motors has said that the Chevy Bolt EV will be able to allow the driver to stop the car without using the brake pedal in certain conditions

The Chevy Bolt is coming with Regenerative Braking

Can someone explain this for me ?

“Bolt EV customers who want an engaging driving experience will love the thrill of one-pedal driving,” said Bolt EV Chief Engineer Josh Tavel. “They will be able to tailor the vehicle to their preferred driving style and maximize their range.”
Progressively stronger levels of regen braking are employed in all Chevy Bolt EV driving through a series of four driver-selectable modes:

  • Operating in Drive and easing off the accelerator;
  • Operating in Drive and using the Regen on Demand paddle on the back of the steering wheel;
  • Operating in Low and easing off the accelerator;
  • Operating in Low and using the Regen on Demand paddle in tandem.


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I"ll try. the first choice operating in drive will give the least regen and will require using the brake to come to a complete stop and hold.
the second choice with the paddle will increase the regen/braking and can bring the car to a complete stop and hold. Note: I am assuming but don't really know that creep is turned on in Drive requiring holding the car with the foot brake but in Low creep is turned off but the car will still hold itself on hills etc.
The third choice in low will bring much stronger regen equal to medium braking which can be increased to strong braking with the paddle. Emergency stopping will always require the foot brake to insure stopping in the shortest distance. I am not sure about the effect of steep downgrades but will assume that is one of those conditions that in some instances will require the foot brake. Also driving on ice and snow will require a learning curve as to which option to choose. There is an advantage to gradual regen braking... Having too heavy a foot on the brake pedal on ice and snow can get you into trouble.

I have test driven the Volt with the regen paddle and found it useful. My I-miev has three levels of regen/braking (D, ECO, B) but the foot brake must be used under 10mph and annoyingly to hold against creep in all three modes. GM listened and has given options. I like what they have done. I will choose driving (with one foot) in Low and using the paddle to stop more quickly if the situation requires and it is not an emergency stop. The engineers say this will increase range about 5% which is a bonus. They have at least two types of customers, newbies to EV's and former EV owners. They need to accommodate both.

There are times in certain traffic situations you might want to stay in drive instead of low. If there is a lot of congestion I can see driving being smoother with less regen. In summary it is up to the driver to pick what they are most comfortable with. One pedal driving for me is a much more preferable way to drive. I'm glad GM is promoting it and I hope their dealers get on board with it too. The Bolt is going to be a lot of fun to drive as well as being practical too.
 

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Low is increased regen so you have to feather the accelerator. It is the basis for one pedal driving. On my i-miev it is labeled B for increased Braking (regen) . It is not the same low as on an AWD vehicle. Another way to think of low is downshifting a clutch car to increase engine braking but regen can be done at any speed all the way down to stop.

This is why you have options. Maybe you don't want to bother with feathering the accelerator. just set it in drive and it performs more like an ICE car. The biggest complaint I have heard is many people want a way to just put the car in the sweet spot of coasting, no current draw or regen, aka Nuetral but this is probably not legal to do. So you train yourself to find the sweet spot by watching the dash display.
 

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I think regenerative breaking options may a breakthrough feature of the Bolt. Perhaps people will look back and be amazed that most vehicles did not recover energy from slowing down as a matter of course.

I'm not a hyper-miler but I do drive a regular Prius now and use my "b" break knob all the time; it's too bad the battery isn't bigger because I love the idea that I'm saving my actual brakes further wear and tear. I trust it'll be a relatively easy adjustment to the paddle. As for one-pedal driving...that may keep the other people in my household from going near it, depending on how I pitch the functionality.
 

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As for one-pedal driving...that may keep the other people in my household from going near it, depending on how I pitch the functionality.
One pedal driving is optional. If you keep it in "D", it will feel very much like an ICE and lifting off the accelerator will be very like the engine braking they are used to.
 

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I enjoy driving my 2017 Bolt around town in one-pedal driving mode using the L position in the transmission. The manual is unclear as to whether there is a maximum speed limit when using L. I am old enough to remember when user manuals gave a maximum recommended speed limit for Low gear (which was a real gear) in automatic transmissions in ICE autos. I am guessing that this does not apply in the Bolt (which, if so, makes me think they could have come up with a better name than "L"). So in short:
Is the Bolt's "L" simply "D" with stronger regenerative braking when easing off the accelerator?
Is it OK to drive in "L" on the freeway at 70+ mph?
If it is OK to drive at 70+ mph in "L", do Bolt drivers on this forum recommend using "L" or using "D" on the freeway?
Thanks in advance for the help.
 

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What I have heard and read is that "L" is OK at any speed. I like it but, I only use it around town. It seems to me that I would be giving the car more control than I am really comfortable with. I still like the feel of actually controlling the actions of the car.
 

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I enjoy driving my 2017 Bolt around town in one-pedal driving mode using the L position in the transmission. The manual is unclear as to whether there is a maximum speed limit when using L. I am old enough to remember when user manuals gave a maximum recommended speed limit for Low gear (which was a real gear) in automatic transmissions in ICE autos. I am guessing that this does not apply in the Bolt (which, if so, makes me think they could have come up with a better name than "L"). So in short:
Is the Bolt's "L" simply "D" with stronger regenerative braking when easing off the accelerator?
Is it OK to drive in "L" on the freeway at 70+ mph?
If it is OK to drive at 70+ mph in "L", do Bolt drivers on this forum recommend using "L" or using "D" on the freeway?
Thanks in advance for the help.
The gearing is fixed in the Bolt. 'L' mode only changes the amount of regenerative braking. You can take the car to the upper limit of 93 mph either in 'D' or 'L' without worries (well maybe the police might take an issue).
 

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sophisticated

Is the Bolt's "L" simply "D" with stronger regenerative braking when easing off the accelerator?
Is it OK to drive in "L" on the freeway at 70+ mph?
If it is OK to drive at 70+ mph in "L", do Bolt drivers on this forum recommend using "L" or using "D" on the freeway?
I drive in L all the time, and there are no speed limitations. Its not a "low" gear, it is just maximizing regenerative braking such that easing off the accelerator brings you to a stop at intersections, etc., without having to use the friction brakes. It has a sophisticated feeling when driving, and it makes it much easier to drive a car than with an ICE car. You just don't have to move your foot to the brake. On highways, I put it in "L" and cruise control and enjoy the ride. Cruise control is much better than in an ICE car.
 

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One collateral benefit I feel I get from driving in L (which I use nearly 100% of the time) is improved reaction time for braking. In an emergency stop, the car begins decelerating much quicker than if I were in D or driving an ICE. The car begins decelerating as soon as I remove pressure from the accelerator and continues deceleration while my foot is moving to the brake (which would be necessary in an emergency).

For instance, sometimes drivers will cut into my lane and I can't react fast enough. But simply the instinctive reaction to take my foot off the accelerator is enough to give me a bit more margin.

Not sure I did an adequate job explaining, but driving in L really comes in handy.
 

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I absolutely LOVE one-pedal-driving! I test drove a Volt and was reminded I have to use the brake to stop!


All electric cars should implement this. Even GM could make the OPD more aggressive. Feather that gas pedal for best results.
 

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What I have heard and read is that "L" is OK at any speed. I like it but, I only use it around town. It seems to me that I would be giving the car more control than I am really comfortable with. I still like the feel of actually controlling the actions of the car.
I drive in "L" at all times. I feel just as much in control of the car at high speeds as at low speeds. In fact, more so - because I can instantly and smoothly control power and braking without having to move my foot.
 

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For a detailed comparison of the different regenerative braking modes, look at the graphs about a third of the way down in the following article:

http://www.motortrend.com/cars/tesla/model-3/2017/the-automobile-2-0-chevrolet-bolt-ev-premier-vs-nissan-leaf-sl-vs-tesla-model-3-long-range/

You can see that the three modes of braking (D, L and L plus paddle) provide varying levels of deceleration. You can 'pump' the paddle too, to modulate the braking level. The Bolt will bring the vehicle to a complete stop using regenerative braking alone, unlike the Tesla Model 3 tested in the article.

I always drive in the forward direction using 'L', and make frequent use of the paddle. But as a courtesy to those drivers behind me, I always put my foot on the brake when I am at a full stop. The brake lights are not on when the vehicle is at a complete stop unless the brake pedal is depressed.
 

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I always put my foot on the brake when I am at a full stop. The brake lights are not on when the vehicle is at a complete stop unless the brake pedal is depressed.
I only afford this courtesy to drivers behind me if I am on a hill and the regen braking can't hold the car. Once I have my foot off the accelerator the car settles back into the stationary position very well most of the time, but not on exceptionally steep hills.
 

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In a conversation with a Bolt engineer, he said, "Anyone who understands how EVs work would always be in L. We only included D because a percentage of test drivers wanted their EV to feel as much as possible just like their ICE. Easier to have D there than to try to educate those who don't want change, even when it's more efficient."

As Raymond Lowey said fifty years ago, "The adult public's taste is not necessarily ready to accept the logical solutions to their requirements if the solution implies too vast a departure from what they have been conditioned into accepting as the norm."

jack vines
 

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I drive in 'L' all the time.
No problem, freeway or surface street.
One thing that a lot of people still seemto have trouble
keeping track of: 'L' is not a different gear than 'D';
it's just a different level of regen available when you let off the go pedal.
You don't gain or lose anything being in 'L' -vs- 'D' other than regen capability.
And... It only says 'L' because Chevy wanted to use an existing gear selector.
Otherwise they might have put 'Max Regen', or 'EcoPlus' or 'TCFW'* or something
on the max regen position. But that would've required manufacturing a different selector.

*Too Cool For Words
 

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Having your brake lights on when you are stopped is a safety thing: mostly the occupant's safety, not the other drivers on the road. If you are at a stop and don't have your brake lights on, another driver may mistakenly think your vehicle is parked or perhaps in motion. You might get rear-ended.

Which car did the Bolt's gear selector come from?
 
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