Now using "D", not "eco" for safety

[JimSouCal]

Looking for confirmation or critique...

After driving ICE cars, I have decided to use D all the time in the LEAF--this is a switch as I was using ECO all the time. The shock of rapid movement, while I accommodated to it, was a concern.

If I understand it correctly, one can garner just as much regen using the brake verses the lift of the accelerator, and with a light touch, drive with similar ease.

I just find that I like the idea that my brake lights come on when I am slowing down (during regen), and also, there is not a big adjustment to the sensitivity on my foot moving the the ICE cars (that while I rarely drive, do drive).

My thinking is that regen is safer to avoid getting rear ended, and I am less likely to surprise myself with rapid acceleration in time pressure sensitive situations.

Do I have this right, as nothing is set in stone, obviously?

 

[EVDRIVER]

No, the regen off pedal is so light it's not going to cause someone to hit you and on the brake the lights will be the same in both modes. I think you are putting too much thought into this but it will likely end up 10 pages long. If it makes you FEEL better then use D.

 

[EricH]

Agree with EVDRIVER - the regen in ECO strikes me as similar to the engine-drag deceleration from an ICE, particularly one with manual transmissions. I can't imagine it would be enough to get you (or me) rear-ended.

 

[EVDRIVER]

Agree with EVDRIVER - the regen in ECO strikes me as similar to the engine-drag deceleration from an ICE, particularly one with manual transmissions. I can't imagine it would be enough to get you (or me) rear-ended.

Eco is dumb, it is designed for inexperienced drivers, just give me the ECO regen on "D" and get rid of ECO. Better yet, do that and make the regen on ECO even stronger. This is a VERY mild EV designed to seem like a car and not scare newbie EV drivers and Japanese folks with steering that can't be done with one finger. :roll:

 

[LEAFfan]

+1(for Eric's) You'll also be getting brake pads a lot sooner and being in ECO, you will use less energy overall, not just the HVAC.

 

[DaveEV]

Eco is dumb, it is designed for inexperienced drivers, just give me the ECO regen on "D" and get rid of ECO. Better yet, do that and make the regen on ECO even stronger. This is a VERY mild EV designed to seem like a car and not scare newbie EV drivers and Japanese folks with steering that can't be done with one finger. :roll:

D is dumb, it is designed for inexperienced drivers. Throttle response is so non-linear you end up pushing 80kW when you only have the gas pedal pushed down halfway and then you start letting up and it keeps power way too high for efficiency. It's very clear that EVDRIVER is scared by the ECO mode and afraid to push hard on the accelerator while using one finger to steer. :roll: :lol:

But seriously EVDRIVER - do you have to go on and on ragging on the car every chance you get? It's very tiresome. The car isn't perfect. We get it.

 

[twbaker]

If you were going down a hill, would you still want to shift into ECO?

I know after driving an automatic ICE for years that when I go down a hill I shift it into "2" and turn off the "overdrive". This takes the pressure off the breaks, and makes your engine do the work to slow down.

How does this functionally compare (between D and ECO) when going downhill in a LEAF?

 

[LEAFfan]

If you were going down a hill, would you still want to shift into ECO?

If it were a steep hill, I would definitely use ECO, but if it were not so steep, I would put it in 'N' and coast.

 

[JimSouCal]

Eco is dumb, it is designed for inexperienced drivers, just give me the ECO regen on "D" and get rid of ECO. Better yet, do that and make the regen on ECO even stronger.

Doesn't the brake pedal use "regen" until max out? The meters seem to indicate it does.

As as aside, I did test drive a Scion conversion with heavy regen on the accelerator lift, and that was enough to rapidly slow the car with no brake lights.

I have never turned on the AC, so have no idea of ECO verses D settings.

But I think you all are missing my main point is the switching back to ICE cars that have relatively steep throttle mapping compared to the LEAF in ECO mode...?

Anyway, my bet is a month in D will be the same as ECO on my efficiency numbers...

 

[LEAFfan]

Anyway, my bet is a month in D will be the same as ECO on my efficiency numbers...

I'll take you up on that bet!

 

[smkettner]

No, the regen off pedal is so light it's not going to cause someone to hit you..... snip

Generally I agree but there are many distracted drivers that may react better to the brake lights than just a slowing vehicle.
Enough to mandate the third brake light not so long ago.
JMHO.

 

[SierraQ]

In any car, every time I have been or almost been rear-ended it was one of two situations:

1) Sudden stop in fast-moving traffic. This is usually my fault as I was too close to the fellow in front of me.

2) Dead stop in a jamb and person behind is asleep from the repetitive creep and stop motion or distracted.

In both cases the brake will be applied and hence the brake lights on. I have never seen anyone fooled by the regen braking (which I agree is equivalent or less than engine braking). If you have ever had the misfortune to be behind someone who's brake lights are actually out, you'll know the difference between engine/regen braking and real braking w/o lights. One is very scary, the other is not.

The only concern I have about ECO is that the power curve at the very end shoots up dramatically so it's like the car suddenly breaks free of something holding it back when the pedal hits a certain point. Because of this, I do not drive in ECO if I know I need to do maneuvering. But for a commute I think it works great. Heck it's even turned me into a better, safer driver. (At least during a commute )

 

[Nubo]

If the brake blends in regeneration then I see no purpose to "emulate engine braking" by having always-on regen. If I want to slow down, I'll start pressing on the brake, so bring on the regen THEN. If I just want to coast, I'd rather the car just coast instead of having to hunt for a neutral throttle position. I.e., I know when and at what rate I want to slow down, so how about leaving that decision up to me? Then degree braking regen is controlled by the amount of deceleration I'm commanding and there is no engineering compromise. Makes perfect sense to me....

Gas pedal = go
Brake pedal = slow

Anything that makes me have to fight the car to get my way is nuts.

 

[kovalb]

ECO mode does three things:
1) Lowers the accel-pedal's gain.
2) Increases accel-pedal lift regen.
3) Changes the A/C compressor logic to permit greater temp spreads thereby improving efficiency.

Depending upon how you drive, ECO can be a big improvement in efficiency (like 10%) or none at all. Coasting is more efficient than regen because regen is not 100% efficient. A-pedal lift regen is more efficient than braking because braking blends the disc brakes with regen so that the discs are always ready to fully act in case you need it.

I say different strokes for different folks. If you prefer "D" for whatever reason then use it and enjoy. If you want to use "D" and maximize efficiency then drive gently, accelerating with no more than about 20kW of power, which is what the ECO pedal seems to encourage. Anticipate stops and coast down as much as possible instead of braking, and then brake lightly and at a constant rate. If you are on the freeway using A/C for long period I might consider switching over to ECO to improve the A/C efficiency.

 

[travisty]

If the brake blends in regeneration then I see no purpose to "emulate engine braking" by having always-on regen.

It's not 'emulating engine breaking' - it IS engine breaking in EVs. The engine becomes a generator. It's also how experienced drivers get the most energy from coming to a stop. Never apply the brake until you need to.

If you want to coast while you're driving then switch to N.
Coming up to a red light? N until you need to start slowing. Switch to ECO until you need to actually press the break. Press the break pedal - if you need to force it you applied ECO too late.
(If you go to N then you don't start regen. If the light turns green, go back to D or ECO and you've wasted the least amount of energy)

 

[Nubo]

It's not 'emulating engine breaking' - it IS engine breaking in EVs.

Of course it is real, what I'm asking is why have it? It is emulation in that letting up on the throttle of an ICE car gives engine braking as a mechanical consequence unless the driver shifts to neutral. But for an EV, it's merely a design decision not a consequence. So why do it?

It's also how experienced drivers get the most energy from coming to a stop. Never apply the brake until you need to.

That's getting closer to answering my question. But, what makes this the most energy efficient method? Why can't the regen be blended into the brakes in such a way that friction brakes do not apply until regen is already maximized?

If you want to coast while you're driving then switch to N.
Coming up to a red light? N until you need to start slowing. Switch to ECO until you need to actually press the break. Press the break pedal - if you need to force it you applied ECO too late.
(If you go to N then you don't start regen. If the light turns green, go back to D or ECO and you've wasted the least amount of energy)

I'd rather not have to work that hard to outsmart my car! :?

 

[turbo2ltr]

Of course it is real, what I'm asking is why have it? It is emulation in that letting up on the throttle of an ICE car gives engine braking as a mechanical consequence unless the driver shifts to neutral. But for an EV, it's merely a design decision not a consequence. So why do it?

To recapture energy!

Why can't the regen be blended into the brakes in such a way that friction brakes do not apply until regen is already maximized?

It does do this to some extent. But you also have to take into account that on a full pack , there is no regen available. So if you did what you are proposing, the change in pedal feel from when the pack is full to when it isn't would be quite drastic. As it is now, on a full pack, that first stop can be a bit unnerving..

 

[LEAFfan]

Makes perfect sense to me....
Brake pedal = slow

Brake pedal also = brake pads. I seldom use my brakes and I know the pads will last the life of the car. That's one less maintenance item to have. :mrgreen:

 

[JimSouCal]

Makes perfect sense to me....
Brake pedal = slow

Brake pedal also = brake pads. I seldom use my brakes and I know the pads will last the life of the car. That's one less maintenance item to have. :mrgreen:

Are you sure about this? Based on my very crude experiments in D, the regen function is called forth first, and with greater pedal depression, the pads are engaged.

This is a key question. If the software map for deceleration always utilizes "regen" to a maximum extent first, whether it is by lifting the foot, or pressing the brake, then factually, your statement is not correct, and if the map does change, then you are correct. What is it?

Anyone who really knows and has expertise and not conjecture, please speak!

 

[GPowers]

No, the regen off pedal is so light it's not going to cause someone to hit you..... snip

Generally I agree but there are many distracted drivers that may react better to the brake lights than just a slowing vehicle.
Enough to mandate the third brake light not so long ago.
JMHO.

Tesla Model S turns on the brake lights under hard re-gen. Nissan should do the same.