Drive Mode "D" or "B" and why?

[caross]

So, I'm a new Leaf owner, and an even newer member here... so please forgive if I posted this in the wrong place... or if it was discussed before. Quick search did not bring anything up.

What is the real difference between "D" and "B" drive modes? "B" is clearly more agressive on the breaking, but does it reduce power consumption? Reason I am asking is that, yesterday, on a drive I was on a long downward sloping highway. I was in "B" mode, because that seemed to be the most efficient thing to do. But then it got me thinking... I have a lot less "glide" distance.

So, what gives?

When should I use it? When should I not use it?

Thanks!

 

[apvbguy]

So, I'm a new Leaf owner, and an even newer member here... so please forgive if I posted this in the wrong place... or if it was discussed before. Quick search did not bring anything up.

What is the real difference between "D" and "B" drive modes? "B" is clearly more agressive on the breaking, but does it reduce power consumption? Reason I am asking is that, yesterday, on a drive I was on a long downward sloping highway. I was in "B" mode, because that seemed to be the most efficient thing to do. But then it got me thinking... I have a lot less "glide" distance.

So, what gives?

When should I use it? When should I not use it?

Thanks!

AFAIK it has no effect on driving or power consumption, it does make the brakes "grabbier" for more regen.
If I use the B mode I use it like a downshift on a gasser. I rarely use it at all

 

[evnow]

"B" gives a lot more regen just by releasing the accelerator. With some practice this helps you do almost one pedal driving. It is great for city driving where you have to frequently slow down for traffic lights or just traffic. It is also good when you are going downhill.

D is better for gliding and can be more efficient in relatively constant speed situations like freeways.

I drive almost exclusively in B. BTW, for the '11/'12 owners, this is close to the Eco mode, without sacrificing the acceleration (more accurately acceleration for a given distance of the accelerator).

 

[caross]

Cool, thanks.

It does seem that the Leaf will require some slight variation driving habits - all of which I am willing to do - just takes time to learn tho.

 

[ENIAC]

"B" gives a lot more regen just by releasing the accelerator. With some practice this helps you do almost one pedal driving. It is great for city driving where you have to frequently slow down for traffic lights or just traffic. It is also good when you are going downhill.

D is better for gliding and can be more efficient in relatively constant speed situations like freeways.

I drive almost exclusively in B. BTW, for the '11/'12 owners, this is close to the Eco mode, without sacrificing the acceleration (more accurately acceleration for a given distance of the accelerator).

I wish there was an S/W update from Nissan I could opt into to turn my "E" to "B".

 

[wsbsteven]

I started driving in b mode all the time because I was having trouble adjusting to the brakes. In my Prius I could regen brake down to low speeds until I felt the grab of the friction brakes. In the Leaf I brake with the same pressure and I wouldn't slow down much at all so I'd brake more to compensate which then would engage the friction brakes throwing me forward. I found that using b mode to do my regen braking for me gives it a Prius like experience so when I do use the brakes it's a lot smoother.

 

[LEAFfan]

B mode doesn't reduce Power/Energy Usage, but ECO does. I leave it in B ECO not for regen into the pack, but for braking after coasting in N while approaching lights. It's more efficient to coast in N than using regen unless you're going down steep terrain.

 

[DanCar]

B mode doesn't reduce Power/Energy Usage, but ECO does...

Not sure what your trying to saying here, but B mode does reduce power energy usage rather than using friction brakes. It reduces energy usage because energy is put back into the battery pack and thus overall energy usage goes down. Yeah, B mode doesn't lower the climate control usage of energy or anything else similar to what ECO mode does.

 

[caross]

I guess for me it is the goal to use the most efficient use of the battery without "inconvenience" in my driving style.

As it is now, I always drive in ECO mode and in "B" mode for the majority of my drive time.

I'm seeing about 3.9 M/kWh average.

 

[LEAFSpecialist]

The "B" mode actually stands for Brake Mode and was created to allow the vehicle to slow down using more regen braking and less brake.

A good place to use this is coming down steep hills/mountains or in traffic for added regen. It also changes the sensitivity of the gas pedal so you will have to accelerate more to get the car back up to speed.

Hope this helps, and happy driving!

~LEAFSpecialist

 

[caross]

The "B" mode actually stands for Brake Mode and was created to allow the vehicle to slow down using more regen braking and less brake.

A good place to use this is coming down steep hills/mountains or in traffic for added regen. It also changes the sensitivity of the gas pedal so you will have to accelerate more to get the car back up to speed.

Hope this helps, and happy driving!

~LEAFSpecialist

Ah, so then in normal driving situations I am probably losing more momentum than I need to... and wasting power getting back up to speed? I'll play with this a little.

Thanks.

 

[dgpcolorado]

B mode doesn't reduce Power/Energy Usage, but ECO does...

Not sure what your trying to saying here, but B mode does reduce power energy usage rather than using friction brakes. It reduces energy usage because energy is put back into the battery pack and thus overall energy usage goes down. Yeah, B mode doesn't lower the climate control usage of energy or anything else similar to what ECO mode does.

While the extra regen in B mode will put more energy back in the battery pack than friction brakes, if that much slowing is really needed, it is usually better to coast than to use regen. It is easier to precisely control speed in Eco than D and it is easier to coast in N. A very efficient driver would ordinarily use Eco + B and shift to N when practical. As LEAFfan does. Such a driver basically doesn't use friction brakes at all except to hold the car still at a stoplight. It's all about technique. Some of us find this stuff fun. Others can't be bothered and that's fine.

 

[lion]

The "B" mode actually stands for Brake Mode and was created to allow the vehicle to slow down using more regen braking and less brake.

A good place to use this is coming down steep hills/mountains or in traffic for added regen. It also changes the sensitivity of the gas pedal so you will have to accelerate more to get the car back up to speed.

Hope this helps, and happy driving!

~LEAFSpecialist

Is my LEAF broken or are you confusing B mode with ECO?

As I mentioned in another thread about B mode, it's ok to use, as long as you understand that you might have to use the accelerator while coasting just to make the regeneration less aggressive so you can coast longer (just don't push the pedal too hard, so you don't start using energy again).

I have been using the 'Zero Emission' screen to learn when exactly I'm hitting 0kWh (so 0 power usage, 0 regen) when coasting in B. I guess this is the same thing as switching to N, but switching to N can be tricky, and dangerous (not to mention, the one time I coasted out of a driveway, my brakes made a funny noise, regen I guess).

 

[DanCar]

..., if that much slowing is really needed, it is usually better to coast than to use regen. ...

Agree with other statements but this is not practical in city driving. You will have cars mad at your for driving so slow and not easy to predict upcoming light changes. So use B mode to brake efficiently.

 

[apvbguy]

As I mentioned in another thread about B mode, it's ok to use, as long as you understand that you might have to use the accelerator while coasting

if you use acceleration you are not coasting or regenerating, hence the reason why many people do not use the B mode

 

[evnow]

As I mentioned in another thread about B mode, it's ok to use, as long as you understand that you might have to use the accelerator while coasting

Even in D there is a bit of regen - so you need to press the accelerator slightly if you want to coast (or ofcourse use N).

 

[lion]

As I mentioned in another thread about B mode, it's ok to use, as long as you understand that you might have to use the accelerator while coasting

if you use acceleration you are not coasting or regenerating, hence the reason why many people do not use the B mode

When using the accelerator (note how I used the word 'accelerator', not the verb accelerating, big difference) you are coasting if you apply the right amount of force to negate the all the regeneration, but not enough force on the pedal to use any energy (so the power consumption screen on your nav unit shows exactly 0kWh, should look like a flat line).

Pressing the accelerator pedal while coming to a stop in B mode allows you to control the amount of regeneration, so it's not like it's an 'all or nothing' with B. B is extremely useful, you just need to understand that you want to avoid regeneration as much as possible.

But when you do have an opportunity to regenerate, understand that you are still in control of this process with the accelerator pedal, even in D mode as mentioned above. B mode just gives you more 'range' to play with than D. I can see why people dislike B, but it's mostly because it's misused/misunderstood.

 

[dgpcolorado]

..., if that much slowing is really needed, it is usually better to coast than to use regen. ...

Agree with other statements but this is not practical in city driving. You will have cars mad at your for driving so slow and not easy to predict upcoming light changes. So use B mode to brake efficiently.

I entirely agree that in congested conditions coasting in N is not a good idea. However, you can modulate your speed/energy use with the A pedal and coast up to a light if traffic permits. Nevertheless, safety first!

 

[dgpcolorado]

When using the accelerator (note how I used the word 'accelerator', not the verb accelerating, big difference) you are coasting if you apply the right amount of force to negate the all the regeneration, but not enough force on the pedal to use any energy (so the power consumption screen on your nav unit shows exactly 0kWh, should look like a flat line).

Pressing the accelerator pedal while coming to a stop in B mode allows you to control the amount of regeneration, so it's not like it's an 'all or nothing' with B. B is extremely useful, you just need to understand that you want to avoid regeneration as much as possible.

But when you do have an opportunity to regenerate, understand that you are still in control of this process with the accelerator pedal, even in D mode as mentioned above. B mode just gives you more 'range' to play with than D. I can see why people dislike B, but it's mostly because it's misused/misunderstood.

You've described it well, good job! When slowing, speed can be adjusted by feathering the accelerator to modulate the amount of regen used. Using B mode and some practice one should not have to use the brake pedal at all except to hold the car still at a stop (except when making a panic stop, of course). This is referred to in the EV world as "single pedal" driving.

 

[kikbuti]

In my 2013 SL model, I use Eco with both D and B. I leave it in Eco and switch between D and B as necessary. Sometimes when coasting down a long hill, I put it in D and let it coast and pick up speed. In stop and go traffic, I use B so that I don't have to use the brakes as much and as noted in earlier posts, the brake pedal use is more pleasant in B mode. When fenced in by impolite impatient drivers in heavy traffic, I turn off the Eco and kick some ICE butt.