Using brake pedal vs. D modes

[turp]

A lot of folks seem to advocate one pedal driving (with most using D-) to maximize regenerative braking and thus increasing battery charge and range and efficiency.

Is that really much better than simply using an anticipatory driving style and light application of the brake pedal? Light application of the brake pedal should only engage regenerative braking and not the actual brake disks (until low speed) right?

We've had a 2015 b class for a few weeks now and I've been experimenting with drive styles. The paddles are fun for me and I like one pedal driving but my wife would probably prefer a simpler driving style (I doubt she will ever use the paddles).

 

[Lukeetal]

I don't like the pedal personally. Based on what I have read about ranged from drivers who use them it doesn't look like it increase or decreases range. Or at least not significantly.

Let us know who get better range.

 

[JeffRay]

Personally, I don't bother as I have ready access to recharging as needed. In D-Auto, it does a good job so I just have to remember to let the engine brake the car vs. stepping on the brake. I have radar assist which likely feeds into the process. Forgive me but I am stupid and initially got the D- and D+ mixed up but learned after reading the posts on which is which enough times. Others who have mastered the manual vs. auto report better range. I feel good enough to be using electric to have to eek out a few more miles by going manual.

Bottom line, it is like manual vs auto transmission for those who remember that. Wanna feel in control and get longer range, use manual. Don't wanna, go auto.

 

[bcurious]

A lot of folks seem to advocate one pedal driving (with most using D-) to maximize regenerative braking and thus increasing battery charge and range and efficiency.

Is that really much better than simply using an anticipatory driving style and light application of the brake pedal? Light application of the brake pedal should only engage regenerative braking and not the actual brake disks (until low speed) right?

We've had a 2015 b class for a few weeks now and I've been experimenting with drive styles. The paddles are fun for me and I like one pedal driving but my wife would probably prefer a simpler driving style (I doubt she will ever use the paddles).

I use D- all the time and I enjoy the process of using the "throttle" pedal to modulate between coasting, light regenerative braking, stronger regenerative braking, and then touching the brake pedal (rarely) to get full regenerative braking. I find it difficult to sense when the brake pedal is producing maximum regenerative braking but no friction braking, so my reasoning is that by anticipating slowdowns/stops and not using the brake pedal unless necessary, I am ensuring that the most regenerative braking possible takes place, albeit at perhaps a slower rate and over a longer distance. If there was a definite "notch" in the brake pedal actuation that indicated the start of friction braking, I'd certainly use the brake pedal instead, as it's nice to have the brake lights illuminated while regeneratively braking. Watching the gauge needle in the instrument cluster helps elucidate how much charging is happening and when, in reaction to your control of the pedals, and the only reason I can see for not using the D- mode is in the case that you're a driver who doesn't trust the regenerative braking to occur and likes to constantly "cover" the brake pedal without pressing it, or even to press it only lightly, but are disrupted by the regen braking that occurs while you're moving from one pedal to the other. Of course you "could" train yourself to use the paddles to switch modes back and forth in that circumstance, but I'm of the opinion that real thing worth training oneself to do is to trust the regen braking and learn how to coast with one-pedal driving. It can be distracting to monitor both the "charging" gauge and traffic while doing this, but I find that switching the entertainment system display screen to System and selecting the energy flow display makes it easier to see at a glance or via peripheral vision than it is to focus on the instrument cluster gauge. After a bit of training, one learns/memorizes the position of the accelerator pedal that produces coasting. There is also always the left foot which can initiate brake pedal coverage during uncertain traffic situations while maintaining the coasting accelerator position with the right.

I don't know that this driving technique produces a significant amount of recharging, but I do know that it can't be producing less than another method, so I choose it whenever possible. If there was a way to select the maximum amount of regenerative braking, beyond even the level of D-, I'd select it! Driving a car like the Tesla Model S with its stronger regenerative braking is a treat in traffic, and even easier to maintain the coasting position with the right foot only.

I might also add that my wife drives the B-Class in D-Auto and focuses on achieving driving scores in excess of 95% most days. She chides me for my driving style when I'm accelerating quickly and is surprised on the occasions that my heavier-footed acceleration driving style can still produce similar scores to hers when paired with greater regenerative braking use. She beats me every time on acceleration scores, I beat her on braking. I enjoy short bursts of max power and long descents of constant speed modulated (in D- mode) only by my right foot.

 

[vin]

I keep it in D Auto most of the time since I'm still in the honeymoon phase and find it entertaining to discover who will brake first (me or the car) when in moderate freeway traffic. When coming to a stop in city traffic, I tend to use D- first, then brake. The D- regen on this car is so strong compared to the other EVs we have, and so I usually don't have to brake until we are at something less than walking speed. Not sure how much (if any) effect this behavior has on range.

I am under the impression that D- coupled with no throttle input provides max regen, because the power gauge drops to its lowest point under those conditions. Is this not the case?

 

[Stretch2727]

D- around town. Try to mostly drive with one petal and avoid the brake unless I need to. I know the brake will also add regen but it is hard to know how much is the friction brakes and how much is regen.

D+ on the high way as I don't want the car accidentally going into regen unless I really need to slow down. Better to let it coast even if it picks up a small amount of speed on a down hill. Regen will recover some percentage of the kinetic energy but not all of it. So you want to avoid toggling between acceleration and regen unless you need to. (i.e. around town.)

I think doing this will give you the best efficiency.

Don't like D auto at all. I want to know how the car will behave. In D auto I also need to move my foot to the brake if there is a stop sign and nothing in front of me. Many times I can coast through at the speed the regen has decelerated the car.

 

[bcurious]

I am under the impression that D- coupled with no throttle input provides max regen, because the power gauge drops to its lowest point under those conditions. Is this not the case?

vin - It may function as you've described at higher speeds. At, say, 35mph or less, in D-, with no foot pedals being actuated at all, I don't see the gauge at it's maximum point. Touching the brake pedal (or romping on it) produces a larger reading on the gauge for me.

Speaking of transmission-y behavior, I wish that in a mode like D-, or in some other selectable menu, that it would also disable the creeping from a standstill operation that is meant to mimic a traditional automatic transmission combustion engine vehicle behavior. A pretty small thing to have to "live" with, overall.

 

[JeffRay]

On the advice of the more learned, am trying D- for urban driving. Today it was 17 degrees so every extra mile will be a bonus. I left the car at 92% Sunday and at work, it is down to 60% having driven 10 miles. So like last winter, I am getting around 35 miles per charge in cold urban driving conditions. Gotta adjust my routine clearly and figure when during week I can get a full recharge vs. daily partials.

 

[bcurious]

On the advice of the more learned, am trying D- for urban driving. Today it was 17 degrees so every extra mile will be a bonus. I left the car at 92% Sunday and at work, it is down to 60% having driven 10 miles. So like last winter, I am getting around 35 miles per charge in cold urban driving conditions. Gotta adjust my routine clearly and figure when during week I can get a full recharge vs. daily partials.

Jeff - I have more helpful experience to offer regarding practical usage improvements for cold weather range than for regenerative braking. We're 150 miles north of you, and further from large bodies of water, and have probably used the car in colder weather and for longer average daily distances. Use the in-car computer's E-Cell setting for departure time. It's a bother, but it helps substantially. The regen function helps more for bragging rights and entertainment, if that's your thing. When it comes to cold, using the battery preconditioning (not just the climate control remote controls) to prepare the car has made enough difference in our daily commuting use to no longer have to do mid-day charging, which for us required remote parking locations and 2 bus rides. Good habits with the regen make a noticeable difference under favorable conditions. Good habits with the preconditioning for cold weather obviate the use of good regen habits. Compared to teaching yourself to drive differently, with learning the in-car computer's preconditioning settings you likely have double the available cold weather stored energy savings for half the training effort. My wife and I drive the car differently still, but we easily agree on using the preconditioning. You can store up to 3 commonly used times of departure, minimizing the hassle of setting your departure time with up and down arrows. When in doubt, set the departure time optimistically early. In case you're plugged in while the preconditioning happens and your departure time comes and goes, the car will begin charging at the departure time automatically.

 

[turp]

Thanks for all the replies and discussion. I'm still experimenting with how to drive the new car efficiently. I've found that D auto is not as "dumb" as some say. But a paddle here and there definitely helps avoid using the brake pedal or extending a good coast. Drove 2 days in a row of 60miles, mostly freeway. Driving 75 (give or take) and looking to draft a little I found the range is as advertised maybe a little better. Driving a little slower I bet the range goes over 100...

 

[JeffRay]

Turp, glad we could help.

BC, never knew that. Sounds different than setting the climate control on remotely via the app. Will this work for me as I park overnight on the street unplugged? If it warms battery, it will use juice but presumably less than driving on a cold battery, correct?

Update: I looked this morning and it seems to be related to the climate control as it was set for same time, i.e. 7:15 a.m. departure. Also, do I need to push the button in control area to activate, the one that looks like heat emanating from a wave?

 

[bcurious]

Turp, glad we could help.

BC, never knew that. Sounds different than setting the climate control on remotely via the app. Will this work for me as I park overnight on the street unplugged? If it warms battery, it will use juice but presumably less than driving on a cold battery, correct?

Update: I looked this morning and it seems to be related to the climate control as it was set for same time, i.e. 7:15 a.m. departure. Also, do I need to push the button in control area to activate, the one that looks like heat emanating from a wave?

It's different from setting the climate control remotely, yes.
I suspect that this is one aspect of the difference in popular approach to internet security between here and the M-B product team "there."
You set the preconditioning departure time via the steering wheel buttons. I'm going by memory here, but here is what I think that I do:
Turn key to on
Use the left hand arrow buttons to select the Settings menu
Top entry in the Settings menu is E Cell - choose that
Top entry in the E Cell menu is Departure time "A," or which there are A, B, and C, and it will prompt you with "hit OK to change time."
hit OK to start setting the time for Departure time "A," which will be saved in memory in case you use that time again.

The departure time will be displayed when you check the app, I believe under charge profile, but you cannot edit the time from the app.

This will use some charge, yes, for example yesterday it consumed the charge from 62% down to 55%, but the total process of warming the battery and driving seems to be less impactful to remaining charge when performed sequentially instead of concurrently. From what I understand, through talking with owners of other brands of EVs, some cars simply delay the charging cycle in order to complete charging at your departure time, using only the warming that occurs as a result of the charging process. The fluid-regulated battery temperature control system is a more technologically sophisticated way to manage this. I've been trying to master a process of using both a delayed charge time and the preconditioning in order to result in a fully-charged and fully-preconditioned car at minimal draw through the charge port. That's just entertainment. The more important discovery for us was that the preconditioning was very important to cold temperature range.

 

[JeffRay]

BC, thanks again. I did do what you said so beginning tomorrow, we shall see. Do I have to hit the little button with the heat rising from a wave?

 

[bcurious]

BC, thanks again. I did do what you said so beginning tomorrow, we shall see. Do I have to hit the little button with the heat rising from a wave?

Great, I'd love to hear your results.
As far as hitting any other button, I'd say no.
I'm not sure which button you mean, actually. If it's the range extension charge button, then no. Whatever it is, it isn't required in order to initiate the scheduled preconditioning feature.