Best And Worst Electric Cars For Regenerative Braking

JAN 15 2019 BY BRADLEY BERMAN 116

Not all EV braking is created equal.

When I drive an electric car for the first time, I’m always struck by how different it is from EVs that I previously experienced. More often than not, what separates them is not how they accelerate or handle – but how they brake.

In the last couple of months, I’ve been able to get behind the wheel of these six EVs:

  • 2019 Hyundai Kona Electric
  • 2019 Audi e-tron
  • 2018 Nissan Leaf
  • 2019 Tesla Model 3 Performance
  • 2017 and 2019 Chevy Bolts (The 2017 model is my personal ride)

The key question for me is whether or not these EVs offer one-pedal driving. That’s the use of strong regenerative braking in which lifting your foot off the accelerator – but not touching the brake pedal – is all it takes to slow the car down to a complete stop.

The idea is to maximize the amount of energy you put back into the battery in the braking process. But the makers of these EVs take very different approaches.

Brakes Like a “Normal” Car

The brake-feel of the Audi e-tron and Hyundai Kona EV is aimed at familiarity with conventional drivers. It’s not that one-pedal driving is impossible. But it takes some work to set things up via a buried menu mode in the Audi or by using steering-wheel paddles in the Hyundai.

Audi e-tron

If you just step on the brake pedal in Audi e-tron or Kona EV – respectively up to 0.3 g and 0.25 g – then the energy will be regenerated. Beyond those levels of force, friction braking is employed to bring the car to a stop.

This approach has a definite effect on how the car feels on the road. If you’re traveling above a few miles per hour in these vehicles, and you take your foot off the accelerator, these vehicles coast just like you would expect from a conventional car. You almost never experience the grab of the regenerative brakes to slow you down.

It would have been easy for Audi and Hyundai to offer a mode or setting to give EV drivers an accessible option for one-pedal driving. They decided against it because they believe consumers don’t like to slow down too fast without using the brake pedal. Besides, they believe, you can get the same level of regen energy (and added range) without changing the drive feel.

Strong Regen Braking But It’s Comfortable (And Easily Controllable)

Meanwhile, based on a few days behind the wheel of the Model 3, I believe that Tesla sets the gold standard for EV braking feel.

If you use the Normal setting for regenerative braking, you promptly slow down – but it’s not too fast. It feels smooth and natural. There’s no stickiness and presumably a maximum amount of energy is regenerated.

Tesla Model 3

Critically, Model 3 drivers also have the “Low” option. That switches the braking to a conventional feel – something like I experienced with the Audi e-tron. I preferred Tesla’s  Normal setting, but it’s nice to have two simple choices.

My Chevy Bolt is similar, with some key distinctions. With the Bolt in Drive, the regenerative feel is moderate, roughly equivalent to what I experienced in the Model 3 in Normal mode. I’d say the Model 3 in Normal slows you down a little faster than the Bolt in Drive.

Chevrolet Bolt

However, the Bolt offers an L gear (or a single function steering-wheel paddle). Use either one, and the Bolt comes much more quickly to a stop. As with the Model 3, the Bolt’s two simple choices provide all the options you need. In fact, in my car, I’m constantly shifting the Bolt into L for higher regen and back to D for longer stopping distances. The ability to toggle with the gear shifter is easier than changing the Model 3’s screen-based setting.

A Feeling of Brake Resistance Rather Than Control

My least favorite braking experience was with the 2018 Nissan Leaf. Yes, it provides the ability for one-pedal driving by using the “e-pedal” button on the console. But I repeatedly had a sense of needing to push through the brakes rather than modulating the speed with the single pedal.

The feeling of resistance was most pronounced at low speeds, when backing out of the driveway or finding a spot in the parking lot. From my perspective, the calibration is off. Even when other cars – like the Model 3 and Bolt – are utilizing strong regen, they don’t feel stiff after a stop and at low speeds.

2018 Nissan Leaf

Sam Abuelsamid, a senior research analyst at Navigant Research, explained the Nissan e-pedal system to me. “Nissan uses the brake actuator from stability and traction control,” he said. “Even if you don’t touch the brake pedal, it will automatically apply friction brake force.”

Abuelsamid contrasted Nissan’s brake approach with how General Motors feeds some current to the Bolt’s brakes to electronically control the regen feel at low speeds. “The potential advantage of GM’s approach is you are not transitioning from one mode to another,” he said. Instead, the Leaf’s transitions from regen to friction braking create “the potential for the handoff to have a little bit of hiccup.”

If you drive one or more of these cars, let us know if you agree with these observations. And tell us which approach you prefer.

Categories: Audi, Chevrolet, Comparison, Nissan, Tesla

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116 Comments on "Best And Worst Electric Cars For Regenerative Braking"

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I drive the bolt and really love the regen braking. I drive in L all the time and have mastered coming to a dead stop without using the foot brake except for quick stops. My next car most likely be a Tesla Y when it comes out or maybe a Rivan

My 3 doesn’t slow much beyond ~7mph. I have to allow for some coasting room if I don’t want to use the brake.

Any EV has to use the friction brakes to come to a complete stop and stay stopped until you push the accelerator. The systems cannot regenerate during the lowest few mph. This is what the Nissan does with the e pedal. In most EVs (and hybrids) the brake pedal also activates regen but only up to a certain level which varies somewhat with speed and then starts to apply the friction brakes above a certain threshold. On Tesla vehicles the brake pedal ONLY activates the friction brakes allowing them to feel more natural but not adding any regen above what is set as the default level.

That is not true, not only can they come to a complete stop but they can maintain position on a hill without using the friction brakes. Regen isn’t the only means by which braking force can be generated from an electric motor.

The i3, unlike the Model 3, will stop completely without using friction brakes. I know this because our brake rotors are somewhat rusty from rare usage, so they are easy to hear when used.

However, as you correctly point out, regen alone cannot stop a car, so I’m guessing that a bit of reverse electric power is applied to bring an i3 to a full stop. I have become spoiled by having to use the friction brakes only when an unexpected deceleration is required (e.g., traffic signal changing to yellow, another vehicle suddenly pulling in front). I would not be happy with a Model 3 or any other EV that doesn’t stop completely without pressing the brake pedal.

The brakes are used so little under 5 mph that you might not even notice any sound. But as to your brake rust; please use your brakes more often! The rust will eventually destroy the pads when you actually do use the rusty rotors. It’s best to keep your rotors rust free.

Not true. My Bolt in L mode comes to a complete stop without touching the brake pedal and will stay there until i accelerate again unless i am on a hill facing downward.

Next time, you can try with creep mode off.

That Rivian with its tesla batteries fits the specs we want.

Rivian isn’t using “Tesla” batteries… which would be Panasonic cells in a Tesla pack.

It’s not using Telsa battery but 2170 battery cell format that are the same as the one Tesla is using in the Model 3.

“If you use the Normal setting for regenerative braking, you promptly slow down – but it’s not too fast. It feels smooth and natural. There’s no stickiness and presumably a maximum amount of energy is regenerated.”

And how do you arrive at that presumption? AFAIK Tesla always applies friction brakes when you use the brake pedal. Has this been changed? Otherwise you will definitely NOT get maximum regen with the “Normal” setting. You will be turning your motion into heat instead of electricity.

Furthermore coasting is more efficient than regen so I don’t understand the point of the author.

It’s sad that so many reviewers don’t seem to understand this. I guess basic principles of engineering and science are not taught to everyone in schools as they ought to be. 🙁

We can see where the writer has gone wrong when he writes “The idea is to maximize the amount of energy you put back into the battery in the braking process.”

No, the idea is to minimize the amount of energy wasted when driving, which means coasting (freewheeling) as much as is practical. Jackrabbit starts and abruptly braking hard to a stop when approaching a stop light or stop sign wastes a lot of energy, and regen recaptures only a minority fraction of the otherwise wasted energy. From what I’ve read, regen recaptures a maximum of about 35% of the energy used to accelerate the car. That means a minimum of 65% is wasted.

Regen is often overrated, and this article is unfortunately an example of that.

It is most definitely not overrated. People that don’t drive ev can’t understand the hype around it. The thing is coasting may be more efficient but regen is a mile more prectical. When you are on city streets for example, it is more practical to accelerate all the way until you need to brake…but instead of braking you use regen and make your btakes last 100k miles. You get to the stop light faster and drive less time. I hate driving Prius style and coast half a mile in advance of the stop light at half the speed limit just for the sake of being efficient.

What benefit is there to “getting to the stop light faster”? You’ll just spend more time waiting at the stop light. In fact, if you reduce your speed early on, you might take long enough to get to the stop light for it to turn green in the meantime. If you time it right, you can end up being faster than someone who had to stop at the red light, since they still need to get up to speed while you still have some of your speed when the light turns green.

I prefer to be there early and relax than drive at 15 mph and piss everyone around me. Not much of a fan of driving so look forward to AP tech.

And with the etron you can do that and simply stop with the brake pedal while still regain all the speed. If you brake at 0.3G in traffic you will be rear ended.

@Bojan:

Bingo! You understand the principle of not wasting any more energy than is necessary. Mark.ca, sadly, does not.

“wasting any more energy than is necessary”
Oh, please! My average after 20k miles is 4.6m/kWh. Do a test for crying out loud and see for yourself how negligible the difference in consumption is… oh wait…you can’t….you don’t drive ev.

How can regen be overrated? If you need to come to a stop, which is what is being discussed, then regen can do that while saving wear and tear on the brake pads, plus putting energy back into the battery. It doesn’t matter about anything else, but the fact this is what happens with regen and energy lost without it. The biggest problem I see with weak regen is the conversion losses mean you basically lose that energy anyway, but with high regen there are less conversion losses so you gain more of the energy. In my LEAF I can clearly see this effect when low regen might put 0.1% back into my battery but the same stop with higher regen will put 0.2% or even 0.3% back into the battery. Driving down a road for a couple of miles at low regen the battery could go down by 1%, but with high regen it might not go down at all. Coasting results in no energy gain, so without regen on the same conditions there is an over all loss of %. I experience this myself, and always wonder why Nissan didn’t just allow higher regen across more conditions, the… Read more »

“How can regen be overrated?”

Short answer: Keep in mind that regen is a type of braking. Motor braking, but braking nonetheless. Regen wastes at least 65% of the energy taken from the car’s momentum while motor braking; most of the energy is lost rather than recaptured. Contrariwise, coasting (freewheeling) wastes none of the momentum energy, because no braking is involved.

Longer answer: See discussion here:

https://teslamotorsclub.com/tmc/threads/regen-vs-coasting.28314/

“Driving down a road for a couple of miles at low regen the battery could go down by 1%, but with high regen it might not go down at all.”

Apparently you don’t realize you just made a perpetual motion claim. 🙂 So I hope you’ll forgive me for some skepticism regarding that.

Have you driven a Tesla? It sounds like you don’t understand what the author is talking about. In a Tesla, think of the accelerator pedal as being like the speed control on a slot car. Hold the pedal in one position and you will go a certain speed. Left up and you will slow to a lower speed using regen. Push down and you go faster. Hold in one position and you will use the minimum energy required to maintain that speed. On a Tesla, except for coming to a complete stop, you can drive using only the accelerator pedal. I can go down to about 3 to 5 miles per hour before touching the brake. Once you get used to it, you realize what a pain it is to be constantly moving between two pedals. If regen is on the brake pedal then you have to drive using two pedals except when at a constant speed. I guess that feels more natural if coming from an ICE car but I find it annoying. When I drive my Genesis I am reminded how archaic it feels. I am not nearly as smooth of a driver. I tell new Tesla owners… Read more »

Good to know that Tesla has a Hold mode, which presumably is the opposite of Creep? I don’t think I’ve read that before.

And it’s not that we don’t understand what regenerative braking, or “regen”, is; it’s that we do understand it’s over-rated. Turning up the power on the regen means you’re wasting more energy by losing a lot more inertia every time you ease up on the “go pedal”, and only capturing a minor fraction of that lost energy. Coasting, or “freewheeling”, is far more energy-efficient.

The best strategy for efficient driving in stop-and-go traffic isn’t to turn up the regen. The best strategy is to accelerate gently up to moderate speed, and then coast the rest of the way to the next stop light. Ideally, the traffic will start moving again before you get there, so you won’t have to stop. Coming to a complete stop and starting up again wastes a lot of energy, and regen recaptures less than half of that.

Turning off CREEP just means the car can coast and roll backwards when stopped. HOLD means when you are stopped, if you press firmly on the brake, the HOLD indicator will come on and the car won’t move even if on a slope. You can then take your foot of the brake. The nice thing is that you can then select AP if the road markings are adequate. That is nice in stop and go traffic.

In stop and go I find regen very useful. I doubt the numbers are trivial but I don’t have real world data so it is a guess.

Most premium cars will hold if you pulse the brake pedal once. Some call it hill assist ect.

As mentioned, some of the cars, when applying the normal brake, will also use regen once you apply enough normal brake force. In a Tesla as soon as you lift your foot from the accelerator it’s using regen. You then can supplement that regen braking by lightly using your normal brake. If timed well, you will only need to apply very minimal to no force to the standard brakes for slowing down and then a little force for finally stopping completely, as Teslas creep forward with momentum under say 5-10mph.

The article mentions that this regenerative brake testing is done using one-pedal driving–not using the brake pedal.

But it is worth mentioning for those that don’t know that the Tesla, unlike a lot of electric cars and hybrids, only does regenerative braking with one-pedal driving. The brake pedal only puts on the brakes.

As an owner of a hybrid, at first I complained about that (“why don’t they do it the way I’m used to?”) but the more I think about it, the more I realize the Tesla approach has some big advantages. Braking using the brake pedal is just braking. There’s no ‘modulation’ where it switches between regenerative and regular breaking, which is always noticeable and takes getting used to, even though they’ve gotten better at this transition over the years. It is also very complex. I’ve heard Toyota had to do redesigns at times because ‘bugs’ in its transition could occasionally leave the driver with a very brief but critical period without brakes. It is probably best for safety that brakes be very simple. You press the brake pedal, you get brakes.

Please provide data where this is actually a safety concern. The etron for example applies maximum Regen before the friction break is applied by wire IN ADDITION. There is never a transition. Other EVs use a similar design

Do a search for “Toyota recalls Prius, Lexus hybrid for faulty brakes – NBC News”

In the article:
The incident follows an earlier recall of some fourth-generation Toyota Prius models due to problems with electronic brake software programming. That issue impacted the way the popular hybrid melded its regenerative braking system — used to recapture energy to recharge its batteries – and the car’s traditional, hydraulic brakes.

That earlier problem could create a sense that the brakes would briefly release during an aggressive stop, according to owners who first reported that earlier problem on TheDetroitBureau.com.

I doubt Audi is using the same programming as Toyota. Just because it’s an issue with 1 maker, doesn’t mean it’s an issue for all of them. VAG had 2 hybrids sold, the Jetta and Q5, for a couple of years. I haven’t read/heard any problems regarding their braking abilities. Then again, maybe not enough were sold 😀

I’m not saying there’s any problem with the Audi regenerative braking design using the brake peddle–I’m sure it is fine. I’m just using the example of the Toyota recall to show that complex brake systems have had issues in the past, so I can see the advantage of a simple brake system.

it could create a ‘sense’. Did it or did it not?

“Please provide data where this is actually a safety concern.”

Even aside from the citation which TomN provided, it’s just common sense. Blended brakes are more complex than standard mechanical brakes, which have been tested over decades of use in gasmobiles. For once, Tesla is using the KISS principle, which is absolutely the best approach in a safety-critical situation. Do you really want your ability to brake in an emergency to be dependent on whether or not the electronics are working properly, and dependent on the software not having any undiscovered bugs?

When EVs have been around for some decades, and blended braking systems have been used and tested for that long, so they are thoroughly developed, and no longer being fiddled with in every new generation of EVs, then perhaps it will be time to consider if auto makers should start using them in cars sold to the public. But until that time, sticking with the brake pedal controlling standard, well-tested mechanical brakes is the best approach, and is going to save lives.

From what I’ve read about the E-Tron, you can press the brakes and initiate regen-braking up to .3 g. Additional pressure will use the physical brakes.
Personally, I’m not sure which approach I prefer. I’ve experienced the one-pedal behaviour on a drive of the Bolt, Leaf 2.0 and e-Golf. Initial thoughts were of it being a awkward but I thought I would be able to get used to it.
Using the pedal would feel safer (psychologically) as it would mimic what I’m accustomed to from years of driving. Plus having my foot on the brake would allow me to react faster if anything suddenly happened.
Just my opinion.

In reaction time, one-pedal regen is better as most people aren’t using two feet simultaneously. Lift off accelerator and braking starts already before friction brake is applied.

Not always true. Consider this scenario, you’re coming to a red light, you lift off the brakes, one-pedal kicks in and then suddenly someone tries to cut you off, your foot won’t be on the pedal. That time to react and move your foot to depress the brakes might be too late. I’m not saying that you don’t have the reaction time to hit the brakes, but not all people have good to great reaction times.
Even now, I hover my foot over the brake in case I need to react, knowing that I’m making a decision not to use the friction brakes as much as possible. So for me, I prefer to have my foot on the brakes and if needed I feel I can react faster.

As the owner of a 2013 Chevy Volt, I can say that there have been issues with the regenerative braking and traction control. I have on two occasion, when using “L” to maximize my regen, needed to make a more aggressive stop due to traffic signal that changed. On both occasions, the roads were wet, and I drove over a man-hole cover. As I hit the brakes, the transition between the regen, and the friction brakes along with the traction control made it feel like I lost all braking ability for about 2 seconds. It was probable much less time than that, but it was scary. I have read about the same issue on gm-volt.com forums. So, now when it is wet outside, I do not use “L”.

In Normal mode the Tesla regenerates as you lift off the accelerator pedal, providing max regen when fully off the accelerator (no pedals pushed).

The brake pedal in a Tesla only actuates friction brakes, which is why Low regen mode should almost never be used.

“AFAIK Tesla always applies friction brakes when you use the brake pedal. Has this been changed?”

According to everything I’ve read this is true. So far as I know, that has not changed even with the Model 3.

During braking, a vehicle’s net weight force vector shifts forward due to the effect of the deceleration force. This places more of the braking work on the front axle than the rear, which is why without ABS, friction rear brakes tend to lock up before the fronts in a hard braking situation.

Because Tesla typically uses their rear drive unit as the main regen drive unit, they tend to have less regen than other brand’s FWD EVs and place more of the braking work on the front friction brakes. This gives FWD EVs the advantage over RWD’s for maximal safe regen braking.

I don’t know if Tesla incorporates the front drive units on their AWD versions to help with regen braking. From discussions I saw on TMC, most owners don’t believe they do.

Tesla thought through their drive system so thoroughly, that I would be shocked if they didn’t use the front motor for regen. The dual-motor versions of the S and X are more efficient than the RWD versions of each, and besides the different gearing and the use of induction motors, I would imagine that optimized regen would be part of the reason why.

“I don’t know if Tesla incorporates the front drive units on their AWD versions to help with regen braking. From discussions I saw on TMC, most owners don’t believe they do.”

That’s an important question. I remember being very surprised to read that tests showed the regen with AWD Teslae wasn’t much if any better than with RWD Teslae.

If Tesla doesn’t use regen on the front motor of a two-motor car, that is very strange indeed. If so, they’re wasting a lot of energy that way. As you say, HVACman, there is more potential for recovering energy when doing regen with the front wheels than with the rear. That’s especially true during heavy braking.

This is certainly one area where Tesla can make improvements in the future.

Wow – many of you are completely misunderstanding the point – Teslas get better efficiency in Normal than in the lighter regen mode. Tesla strongly recommends using Normal (which is why they called it “normal”, I would guess).

I will point out that the date when the author used the Model 3 for regen testing is important. Tesla issued an update in the last month where the regen was increased when the car is set to “Normal.” I had to reset my muscle memory in order to not stop short once the update was applied.

Actually, the software update for increased Model 3 regen was issued in November 2018, not December.

> these vehicles coast just like you would expect from a conventional car

Correction: like a conventional car with automatic transmission.

The Bolts “L” setting took a little getting used to but now anything else seems out of control. Using the regen levers in conjunction with the “L” mode add a little extra braking at stop signs. Love it.

Gm really got this part of the Bolt right. It works well and once you use it for a while anything else feels like the car is out of control. I jump from the Bolt to the Volt and hate how the Volt feels in comparison. It won’t stop on it’s own and the regen with the paddle on can not be modulated.

Coming from driving a manual, no car should move on it’s own. Manufacturers, please provide a switch to turn off creep.

Hear, hear! I was appalled the first time I read about an EV that was deliberately engineered with a “creep” mode. That behavior has always annoyed me with automatic transmission cars, and is one of the reasons that I have always preferred a manual transmission in gasmobiles.

A simulated “creep” mode is definitely something which the driver should be able to shut off.

I think Teslas have always had a way to defeat it (without having to reset it every time you get in the car).

In fact, in Teslas, you must select “Creep” in the menu options. No creep is the default setting.

A little? Its in the neighborhood of 100 horsepower of braking when at speed. Berman never experienced it in his test drive of the Bolt since he didn’t know you could combine both “L” and the paddle.

The Volt in “L” is pretty good, but the Bolt combo is absolutely great. Of course, since this is an Evanex article or something they have to say the model 3 is the best. Haven’t test drove a ‘3’ but I was underwhelmed by the “S”.

Has anyone got numbers on how much energy is regenerated comparing a longer, more gradual deceleration in a light regen setting vs. a shorter but more abrupt decel with a higher level of regen from the same speed (say, 50 mph to 0)?

I expected this article to be about such things and not about personal preferences.

Yes, I thought the same thing. Looks like the author is unfamiliar with the various Leaf settings: D, B and e-pedal. I consistently use e-pedal but some in my family prefer B.

Neither really generates that much unless the duration is longer.

That duration is really depended on the grade of the hill.

Strong regen gives the EV best brake free slowing down a large/steep hill at any speed. It also works great on hwy exits.

Less regeneration is going to be more efficient than more regeneration, to the point where NO regeneration is the most efficient – but then that misses the point.

With up to the almost 100 Horsepower of braking effect available with the Bolt, I only need the mechanical hydraulic brakes in an emergency – so even if not the highest efficiency, its not wearing out the friction brakes.

Anecdotally in my 2012 LEAF I gain about 0.1% on the battery when regen is light (10kW) but for the same stop I can get 0.3% if the regen is high >30kW. I think the problem with low regen is conversion losses, same as charging 110V compared to 240V or CHAdeMO, the systems that support the charging are using the same amount of power, so higher charger rate results in more efficient because more of the unit power is getting to the battery in the same time frame.

“Has anyone got numbers on how much energy is regenerated comparing a longer, more gradual deceleration in a light regen setting vs. a shorter but more abrupt decel with a higher level of regen from the same speed…”

A more abrupt decel with higher regen will definitely generate more regen energy. That’s basic physics.

But that is a highly misleading question and answer. The question should be: Which is more energy-efficient: A gradual deceleration with minimal (or no) use of regen, or an abrupt deceleration with maximum regen?

Since regen recaptures significantly less than half the energy used to accelerate, the most efficient way to travel in stop-and-go traffic is to accelerate at a moderate pace up to moderate speed, coast (freewheel) to the next stop light, and if necessary, use gentle regen to brake to a stop. (You get much better efficiency if the traffic starts moving again before you stop!) Coasting (freewheeling) is far more energy efficient than even the strongest regen setting.

Racing from one stop light to another and braking hard when you arrive at the next wastes a lot of energy (and reduces your EV range) unnecessarily.

Pushi claims “…Since regen recaptures significantly less than half the energy used to accelerate….”.

Where does this energy go? The more than half that is not recaptured, per you? OH, you are using Grape as a source authority.

I absolutely love the feel in the Bolt. Feels totally natural now to almost never touch the brake pedal. When I get in my Volvo PHEV, it gives minimal regen when in the “B” mode, and it takes me a second to realize I actually need to use the brake pedal if I want to slow more than minimally.

With Tesla, I was shocked when I test drove the Model S and learned that the brake pedal causes exactly ZERO regen. It is purely friction brakes. So to be efficient, you really need to have it set to maximum regen when lifting off the gas.

How about a chart that shows the maximum regen of each vehicle, either in G’s or kW? I’d love to see this across the board for PHEV’s as well. And how pressing the brake pedal is divided by regen vs mechanical. Does it first max out regen, then go mechanical? Mix the two as soon as you touch the brake?

Interesting about the Leaf that it actually uses mechanical just by lifting your foot off the gas. Are there any other EV’s that do this?

“How about a chart that shows the maximum regen of each vehicle, either in G’s or kW?”

This would be a very interesting chart. Been hoping someone would do this for a while, now… preferably with both Gs and kW.

“Interesting about the Leaf that it actually uses mechanical just by lifting your foot off the gas. Are there any other EV’s that do this?”

The i3 will use friction brakes when lifting off the accelerator, but only in a unique scenario: It uses friction braking to *simulate* regen braking when the battery is at ~100%. That way, the driver always gets the same response when lifting off the accelerator, rather than being surprised that the car isn’t slowing down when they’re expecting regen.

The Bolt will provide up to 70kw regen using the paddle.

Pretty close to that in L down steep grades too. I regained nearly 90 miles of range driving downhill from Eisenhower Tunnel to Morrison this past summer. Enough range to get me home!

I can find that 70kw is the max regen for the Bolt. The Model 3 used to have 60kw for the max regen until it was increased by a software upgrade in November 2018. I haven’t been able to find the new kw, but I assume it’s around the same 70kw as the Bolt now.

I owned an i3 for 4 years and used to go to the cottage at the top of a hill. When I was leaving with a full battery, I was getting regen and although the battery showed 100% it was charging to about 103% (displayed SOC is not actual SOC so even if it showed full it still had some room for extra electrons). I was able to drive a few miles before seing SOC starting to decrease which at first surprised me. Never heard/felt friction brakes on my descent, but I had one of the very first i3 and no OTA updates so I guess i3 mileages may vary depending on generation…

Bolt regen (L mode) is generally enough to stop in almost every situation. Occasionally add the paddle when L is not enough, and try to use the brake pedal every now and then to keep the pads and rotors healthy. I find driving my wife’s ICE a challenge now, I kind of forget to use the brakes sometimes and react late.

You should drive the i3. It’s set up for 1 pedal driving by default. No special settings or goofy paddle gimmicks needed.

The flip side is it is *only* set up for 1 pedal driving, and there are no options to change it. So those that don’t like that aren’t going to like the i3.

Agreed. I love the one pedal driving our i3, but I always wondered why BMW didn’t offer a setting for lighter regen. I like heavy regen, but I’ve noticed passengers getting thrown forward a wee too much for their comfort. A lighter setting would be convenient in those instances.

No need to throw around i3 passengers during regen braking. The driver has complete control of the regen braking power using the power pedal including true coasting. I don’t totally lift my foot from the power pedal in our i3 unless I need full regen braking power. So just back off the power pedal more gently to avoid throwing i3 passengers forward.

This is no different from applying friction brakes. If the driver suddenly presses the brake pedal hard, passengers would be thrown around.

Was one of my favourite feature of the i3, still miss it after 5 months in my Model 3 although I prefer the Model 3 overall by far

My 2015 i3 will come to a dead stop on level ground or uphills without touching the brakes, but it will roll forward on downhills. So unless you live in a very flat environment, it is only a partial 1-pedal solution.

Or did they fix that in more recent versions?

I think maybe they fixed it.. I haven’t noticed my 2018 i3 rolling forward on downhills, and it will apply the brakes if the SOC is full.

Did you get the opportunity to drive the E-Tron? Are your preferences based on the fact that you’ve driven and are used to your TM3. What if this is a person first foray into BEV ownership? If you look at it from that perspective, what would you think of the different approaches?

For efficiency, one should reduce regen (and no friction brakes) unless it cannot be avoided. For wear (tire and others), jerk should be avoided; if you ride a motorcycles, you’re probably aware of chicken strip and how that gets wider the older you age.

For those reasons, I keep it in D instead of L with Bolt since it has blended regen brakes, especially when in cruise control to reduce jerk (da/dt) when coming out.

A quick burnout donut left then right takes care of that chicken strip….LOL .

So the E Tron has the option, but you think it is to cumbersome to select it in in a menu once?

By the way from an efficiency standpoint it makes sense to use coasting and only regenaration activated by the break paddle when you want to break. Otherwise you lose every time the battery – to wheel – to battery heat losses.

Again, not a fan of Audi but their system seems to be the best and that is what I want in my next car. This way you decide how much regen/friction/power is needed for your circumstances. And if you pay attention to the road, the brake pads should never move but your foot is right there if they are needed.
This “article” is an opinion and the personal preference of the author. No data regarding how (efficient) these systems are working is provided.

I read this often but don’t understand why different regen settings are necessary when the regen power is infinitely adjustable up to the maximum based on the position of the power pedal. It’s like drivers just lift completely off the power pedal when deceleration is needed rather than adjusting the position of the power pedal to produce the desired regen. At least, this is how it works in our i3…

Bolt is pretty much the same way. It does offer a paddle to switch between 55kw and 70 kw max. That works well as most times you don’t need more than 55, but if you do, pull the paddle and then it’s 70 which can be adjusted with the go pedal. When it’s handy is you didn’t plan well enough and need more deceleration. I think driving with 70 kw all the time would be a bit jerky for most people, by having the lower setting it’s smoother most of the time yet allows faster stops if needed.
IMHO the only time I don’t like strong regen is in the snow. Unfortunately I can’t turn off creep which the Bolt in drive. The ideal programming would be to have a switch for creep, then the D and L with paddle. For me, turn off creep and if I want to drive with regen, then that’s L. For snow, use D since traction can’t handle the regen, yet the car would stop on its own. Then for a faster stop you tap the paddle.

The L mode in the Bolt and Volt are amazing. Once you are used to it, you wouldn’t drive in any other mode.

There is actually some correlation to ICE cars. Anyone who drives stick shift knows that when the ICE car is left in gear, it will slow down on its on. The difference is that ICE car will be loud with engine moaning where the EVs are still quiet and putting electrons back into the battery.

“Anyone who drives stick shift knows that when the ICE car is left in gear, it will slow down on its on.”

Right. Engine braking in a gasmobile works in a manner similar to regenerative braking — which is motor braking — in an EV. The difference is, as you said MMF, that in the EV, the braking actually recovers some momentum energy, whereas in a gasmobile it merely converts momentum to waste heat.

Thank you for this article and glad we’re discussing this. Since each of us has a different perspective, I believe manufacturers should provide us with options, such as –
* Many more regen intensity options, easily changed on the fly, and including a zero-regen setting
* Single-pedal full-stopping capability without applying the brakes (the Bolt does this)
* Creep disable
* Regen paddle control with regen intensity proportional to paddle displacement
* Cruise control offering either constant speed or constant power (for hypermiling)

I personally prefer very high regen for city and mountain driving, but would like zero-regen for highway hypermiling as I’m getting tired of constantly kicking the car into neutral. Some of us have early very low-range BEVs which react wonderfully to proven hypermiling techniques.

It really bothers me that Tesla’s cruise control constantly blips the car into power or regen in order to maintain a constant speed (think overpasses). Wasteful, and easily remedied by a constant-power setting which, while not maintaining speed precisely, avoids those energy-robbing blips.

Recognize that front-wheel-drive can offer a higher regen (deceleration) than rear-wheel-drive, the limit being wheel lockup. Wasn’t that the main reason Aptera changed their design?

Joe, I’m guessing that you and I have conversed in the past about our i-MiEV’s. We replaced our i-MiEV with a 2014 i3 BEV due to its greater range. After more than 4 years’ driving experience, I do not understand why people feel that multiple regen settings, paddles, etc., are necessary. An i3 driver can control regen strength from true coasting to maximum regen power which is substantial with an i3 using only the power pedal (f.k.a., accelerator or gas pedal). Unlike the Model 3, an i3 will stop completely without pressing the brake pedal for true 1-pedal driving. Why make regen any more complicated than necessary?

Greetings Alohart. Coasting is one of the easiest and simplest hypermiling tricks. On downhills with the i-MiEV I just kick the car into Neutral and then slow down as needed by selecting the appropriate amount of regen with the ‘shift’ lever. Unlike you, I find it impossible to keep my foot on the accelerator at the ‘zero power’ point. My previous Gen1 Honda Insight modified with MIMA allowed me to infinitely modulate the amount of regen with a joystick – a feature I absolutely loved and would like to have it on every one of my BEVs. I’m envious of the paddle on my brother-in-law’s Bolt, and sure wish my Tesla S85 gave me manual control over regen – fingers are a lot more sensitive and precise than one’s leadfoot. 🙂

Yeah, I would think it would be almost impossible to keep the “go pedal” depressed to the exact point at which actual freewheeling is achieved… altho I suppose the car could be engineered to make it easy to “find” the freewheeling point, by providing that over a range of pedal pressures, rather than one precise level of pressure.

What I’d love to see is the level of regen fully controlled by steering wheel paddles; rather than have levels of regen, have the right paddle smoothly increase regen up to max and the left paddle smoothly decrease it down to zero. Or perhaps vice versa, if you want the left paddle to mimic the action of the brake pedal.

As several comments have said, pressing the brake pedal in an EV should only be necessary in an emergency.

A high regen setting would certainly be best when driving down a mountain road. I have yet to see any argument that I find persuasive that it’s actually better (in terms of energy efficiency) in any other driving situation.

But it’s clear from some of the comments here that minimizing lost energy isn’t an important goal for some EV drivers. If you’re in a hurry to get where you’re going, and so you’re doing lead-footed driving, then a heavier regen setting may be a bit more efficient. I don’t know; I’d like to see a properly controlled study of that with various EVs to see what actual measurements show.

The statement about the Bolt is not correct. Every EV with one pedal driving uses the mechanical brakes for the last little bit. This is not unique to the Leaf. You can’t regen to a stop.

This is outside my area of expertise, and I simply don’t know if motors containing permanent magnets (such as the Bolt and Tesla Model 3) behave differently than ac induction motors (such as Tesla Model S) when it comes to regen at very low speeds. If employing the brakes to fully stop, the Bolt’s transition at very low speeds is certainly seamless and a tribute to its design.

While it’s true that regen cannot decelerate to a full stop, not all EV’s with 1-pedal driving use friction brakes to stop. I can hear the friction brakes in our i3 due to a bit of rust on their rotors, so I know that they aren’t being used to bring an i3 to a full stop. Instead, an i3 must use a bit of reverse electrical power applied to the motor to bring an it to a full stop.

It’s true that you can’t regen to a complete stop, but an EV could be (and perhaps some are) engineered to provide reverse motor torque to bring the car to a stop without any use of mechanical brakes. In fact, I recall one EV prototype with 4 in-wheel motors which didn’t even have mechanical brakes; the motors were powered in reverse to provide braking.

You’re mistaken. The Bolt does not use the regular friction brakes to come to a stop, it uses regen and motor torque. Once the vehicle is stopped, motor toque holds it in place. If it can’t hold the car in place and the car is starting to edge forward again after stopping, it’ll apply the parking brake. The only time the Bolt applies regular brakes by itself is if you’re held in place by significant motor torque or moving slowly and you put the car into park. Then it uses the emergency (collision avoidance) braking system, which makes a horrible sound and causes most Bolt owners to think they’ve done something destructive to their transmission and vow to never put the car in Park without first applying some kind of bake.

Could you please advise, is it possible to set the eTron to deliver one pedal driving on a permanent basis? Ie, change the menu in the options once and it’s turned on until you turn it off again? How does it compete with the Model 3 once that has been done?

I’d really like to understand if the regen braking in the eTron requires mucking around every drive, or if it’s just a quick one-off setup and then it offers Tesla levels of performance.

Thanks for that, I’d forgotten that article. Does that setting persist though? Or does it get cancelled when the vehicle is turned off and have to be set back to manual every time you start up? And what is the feel of the Audi set to Manual vs a Tesla? That’s what I’m trying to understand.

Hey Arnifix. I might have to check with Audi to confirm all the details but here’s what I remember from my drive of the e-tron. Yes, you can set the e-tron to manual to get a persistently higher level of regen without touching the brake. I’m not sure if you need to reset it each time but I don’t think so. It’s essentially the same thing as keeping your foot always slight pressed on the brake (but not really touching it.) Audi argues that it’s better just to use the brake. The difference is that using Auto allows you to coast, which is not the case with the higher manual setting. If you use the paddle shifter for a temporary higher regen, it gets reset when you step on the go-pedal. But the manual setting keeps the higher level. It’s a very different experience than Tesla, which slows down faster with the Normal setting than you do even at the highest level of manual higher regen on the Audi. To me, Tesla strikes the right balance of ease, smoothness, and a definite EV feel. The Audi always feel a lot more like an ICE car. I hope this makes sense… Read more »

That was exactly what I needed to know, thank you! I really like the driving feel of regen in a Tesla too, and this is a definite mark against the e-tron in my books. Trying to understand the vehicle without actually getting hands on is really tricky, so appreciate your help in explaining your experience and how it works.

A lot of strong opinions here. Let me add my $.02 after having owned 3 Volts and now having a Model 3 Dual Motor for 2 months : As some have mentioned, the goal should not be to maximize energy recuperation but to minimize energy utilization getting to your destination. I see one pedal driving as largely irrelevant and mostly a matter of personal preference in most EVs where the brake pedal itself recaptures energy up until the point it no longer can and has to use friction. Unless Tesla joins that crowd, we need to keep regeneration on “normal” mode or we will be generating heat/brake dust to slow down since the brake pedal on the Model 3 is a very old school piece that does no regeneration. Other EVs like the Volt also provide a lot more control mechanisms than Tesla does. On my 2nd gen Volt, for around town or bumper-to-bumper traffic I drove in Sport (quicker response to throttle input) and Low (remapping pedal so regenerative braking occurs early as you release the throttle) mode. It improved response times to gradual slowing and often braking early and coasting to a stop was more efficient than going… Read more »

“Tesla needs to regenerate with the brake pedal…”

But it does. If you take your foot off the “go pedal”, then regen is on full. Pushing the brake pedal engages the mechanical brakes for more braking power.

Perhaps what you meant to say was that you’d like to see this changed, so pressing the brake pedal initially cranks up regen, then pressing the pedal harder engages the friction brakes. This setup is called “blended brakes”, and is used in some EVs. But some of those have been recalled due to inconsistent brake functions.

Just my opinion, but I think Tesla was wise in sticking with strictly friction brakes. Having the brake pedal work in a different manner in different situations would be dangerous. The trained reflexes you develop when driving a car should be able to respond without thinking during an emergency.

In the future, when there has been time for years of testing and all the bugs are worked out, we might advocate for blended brakes in EVs. But so long as they keep fiddling with how they work every year, I think we should stick to the KISS principle for safety-critical systems such as brakes, as Tesla has done.

Not true… Hyundai has the perfect opertunity as you can easily coise your prefered regeneration. It is also not good to never use the breaks in normal drive

I have a 2017 Bolt and use the low all the time. Only way I drive it. I do put my foot on the brake pedal when stopped -in case I get hit from behind. When the battery is fully charged I have found the regen not to work like normal until I have used some charge. That throws me once in awhile. Most of the time I only charge it to 85%.

I spent a while driving a Leaf 40 and a mere 10mins test-driving a Model X last year. That was one of the things that really stood out with the Tesla – the regen (set to strong) was beautifully balanced – lifted off where I thought I should, and it came to a stop exactly where I wanted, at the very first attempt.

Leaf was OK, but TMX took the cake for me.

I think you missed the best in regen braking: the BMW i3. I currently own a TM3 dual, and although it’s good, the i3 regen was strong even when battery was full and the car was coming to a full smooth stop, thanks to the assistance of the brakes for the last 5 feet. This could also be possible in the TM3 as the car is coming to a complete stop while on Autopilot, but it’s not currently the case in regular driving. If there’s a reason I miss my i3, it’s for that.

In my 2012 Leaf running in eco mode, the regen starts when I take my foot off the accelerator. When applying pressure on the brake pedal the slowing down feels a bit weird. The brakes are grabbing for a bit then letting go until the car stops. I’ve talked to the Nissan dealer about it and they say it is “normal”. I haven’t driven any later Leafs so I don’t know if they fixed this anomaly.

I’ve been driving a VW eGolf since 2015 and love the way they implemented regenerative braking. There are 5 levels, from none to maximum. The shift lever can be toggled to the left to increase the level, with each successive toggle increasing the level an increment, and to the right to decrease the level. At any time, the shift lever can be toggled aft to jump straight to maximum, and a second toggle aft to exit maximum. The return-to-center shift lever is easy to use and gives the driver complete control over how much or how little regen braking is applied at any given time. Single-pedal driving is a breeze, coasting with no regen is easy to invoke to maximize range, and finely-tuned adjustments to the regen level can be quickly invoked as required for the driving and traffic conditions.

I’m at a loss to understand why the Model 3 is declared the winner when the i3 isn’t tested and the Bolt is acknowledged to (a) be able to bring the car all the way to a stop without touching the brake pedal (whereas Tesla’s regen stops once the car is moving slowly) and (b) the Bolt’s regen in L is stronger, and (c) the Bolt applies regen when you push the brake pedal. Berman seems to almost be saying “oh no, the Bolt’s regen is too strong for me”, as if you can’t control it by not taking your foot all the way off the pedal.

Is Berman one of those binary drivers with two foot positions, either on the go-pedal almost flooring it or completely off it?

My Chevy spark ev has great regen in L. I hardly touch the. Old friction brake. It is very smooth. I get 6+ miles per kWh in my spark. Ev and over 120 mile range. Too bad Chevy stopped making them in 2016. They were only $24k and then take off the $7,500 fed incentive and any state incentives.

It’s amazing how someone can claim 1 system to be the best when they’ve likely spend ‘000s of km in 1 or 2 of the cars and <100 km in the others.

I’m curious to see the relationship between regenerative braking settings and tire tread wear. Does the extra resistance applied to the tires via aggressive regeneration cause the tires to wear significantly faster than a more mild or progressive regeneration setting? I’ve got a Fiat 500e that has mild regeneration system that gets more aggressive as you apply force to the pedal. Coasting will yield about 7kW and full braking will yield about 55kW. Our Model S on standard regen will go as for as 60kW and 30kW on low. I’d love to have more control based on my driving/braking habits.

I’ve been driving electric cars for about 7 year now – Leaf/E-golf/A3 etron. I’ve come to the conclusion that I really really do not want any regeneration when I take my foot off the pedal – unless I’m in start and stop gridlock traffic or on twisty mountain roads. I want to coast and glide – not to feel like i’m bogging down in mud. My kudos to the e-tron which I think very simply does it right – glides in regular conditions but one yank of the shifter to sport mode gives you one pedal option for traffic or mountain roads. Not having to switch to the brake pedal when going fast into tight turns is just really nice.

maximum range comes from coasting not regen.
coasting keeps the energy where you want it, in the inertia.
all regen is sub optimal, obviously better than conventional brakes but still far from perfect.
i get maximum electric range in my PHEV with regen switched off and only coming in when i gently touch the brake.
Tesla could (with their road data) minimise regen when road conditions favour maximising inertia, like a descent followed by a hill.
this would help increase driving range for sure.

I totally disagree that Model 3 set a gold standard. I own a S75D and a VW e-Golf, and I find the regen system in Tesla very basic in comparison. Each time you touch the brake pedal in the Tesla you loose energy, and it is not possible to coast – which in my opinion is much more relaxing and efficient, except in the city. The 2014 e-Golf offers coasting AND four levels of regen that can be changed with the gear stick, without taking your eyes off the road. And much like the e-tron quattro, the first 30% or so of the applied brake pedal is also regen. The e-tron quattro and other EVs use paddles at the wheel, and you can do kind of one pedal driving if you really want. I believe this is standard in the Eco driving mode on the e-tron and the Leaf has a setting for this. The e-tron also have intelligent regen, based on the front radar/cameras and GPS data. The ECQ will have the same. Have you seen the e-tron go down Pikes Peak? That’s proper regen, at a rate of up to 220kW. The Model 3 would probably get a… Read more »

I’m glad to see an article on this topic. I’d love to hear some stats on the percentage of power that the regenerative braking system generates on average for these EVs. On average for 2018, my 2015 Nissan Leaf regen performed very well producing 32.1% of the energy used by the electric motor. I typically drove in Economy mode and also shifted into B when slowing down to come to a stop. All this resulted in my Leaf achieving an average of 4.6 miles per kWh (157.2 mpge) for the year. I would sure like to know how the newer models compare to these stats.

I’m very happy and accustomed with the BMW i3 regen. For me, it’s the perfect one pedal driving. In normal traffic I never touch the brake pedal.
My Audi E-tron test drive last week confirmed your observation. Regen, although there are 3 different settings: none, light, medium, is just not enough. To my feeling, medium level could be doubled at least. And the regular friction brake (which starts with heavy regen) is quite heavy and difficult to control.
But, on the brighte side: this can easily be fixed with a software update.