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2017 Flame Red Leaf 30 Acenta
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Discussion Starter #1
I know B Mode provides a stronger 'engine braking' experience as the motor recoups energy more aggressively.

But I was wondering how much regen is there in D mode when coasting on a flat road. I know the car manual indicates that there is some, but to me it always feels more like coasting in neutral in an ICE.

I tend to use D mode mostly, only engaging B in busy town/city environments or when I hit the top of a hill.
 

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Look at the blobs on the screen display to tell. Without braking I get at most three blobs regen in D, but up to five in B (admittedly down a very steep hill).
To me the biggest difference is the change in the "coasting point" on the accelerator between B and D - it's much higher and takes me a while to readjust to when changing between modes.
 

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2017 Flame Red Leaf 30 Acenta
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Discussion Starter #3
Look at the blobs on the screen display to tell. Without braking I get at most three blobs regen in D, but up to five in B (admittedly down a very steep hill).
To me the biggest difference is the change in the "coasting point" on the accelerator between B and D - it's much higher and takes me a while to readjust to when changing between modes.
Yeah I've been watching the blobs. To be honest I thought there was zero regen in D mode just from the driving feel, it was only when I was glancing at the blobs that I noticed a green blob occasionally popping up. That got me thinking.
 

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In a Leaf a good way to check the difference between D with no throttle input and true coasting is to get to 50mph on a straight and level road and knock the gear shifter into neutral. All resistance from regen action is then removed and the car freewheels so that you can notice the difference. In my Ioniq I have a setting in the flappy paddles to select that at any time without being accused of being out of gear and unsafe. It's amazing how far the car will coast, gaining distance without the use of any power, but without causing problems to following cars.

It is perfectly possible to adjust the go pedal slightly to achieve that same freewheeling position but it isn't easy and needs constant incremental changes to sit in the sweet spot between energy input and regeneration slowing. But it's a skill worth acquiring.
 

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In a Leaf a good way to check the difference between D with no throttle input and true coasting is to get to 50mph on a straight and level road and knock the gear shifter into neutral.
I'd be worried about damaging the motor in a LEAF by doing that. No doubt you can get away with it if you are lucky, and @Hitstirrer hopefully has if he's done it in one. The Ioniq and its controls are way in advance of what we LEAF owners are trusted with.
 

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I'd be worried about damaging the motor in a LEAF by doing that. No doubt you can get away with it if you are lucky, and @Hitstirrer hopefully has if he's done it in one. The Ioniq and its controls are way in advance of what we LEAF owners are trusted with.
Done that dozens of times in my Leaf with no problems. I took the view that if the manufacturer made it possible to select neutral whilst moving then they were not too concerned. If they knew that it would cause damage they would have fitted an interlock to prevent selection unless stationary.

Back in the early days of EVs this was a common topic of discussion and over seven years I have never heard of any problems caused by coasting in a Leaf. This forum thread was typical some five years ago.

 

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I've definitely coasted in neutral in Leaf30. What I love about outlander is B0 regen mode which is no regen at all.

I agree if the system was designed to allow you to coast and they didn't think wise to block it over the years, it was by design.

Sent from my SM-G973F using Tapatalk
 

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2017 Flame Red Leaf 30 Acenta
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Discussion Starter #10
@Scorzon do you use eco?
Nope never. Just a light right foot.

I will dip in and out of B mode, a classic example would be leaving a motorway/dual onto a downwards offramp. Otherwise just use D without Eco.
 

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2017 Flame Red Leaf 30 Acenta
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Discussion Starter #11
I was out for a drive today, 30 miles, kept my eye on the Bubble-o-meter and I can see more clearly now that in D there is often a fair bit of regen going on. I guess there is no ISO unit of regen with which to compare modes.
 

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I know B Mode provides a stronger 'engine braking' experience as the motor recoups energy more aggressively.

But I was wondering how much regen is there in D mode when coasting on a flat road. I know the car manual indicates that there is some, but to me it always feels more like coasting in neutral in an ICE.

I tend to use D mode mostly, only engaging B in busy town/city environments or when I hit the top of a hill.
I've just come from a Peugeot Ion (modified to unlock the extra B and C driving modes of the i-Miev) to a Leaf 30 and the regen is..... weak....

D mode feels almost like coasting (not quite) and similar to C (cruise/coast ?) mode on the Ion/i-Miev. B mode feels similar to D mode in the Ion/i-Miev, and there is no equivalent to the B (braking) mode in the Ion/i-Miev which in hindsight has relatively strong accelerator lift off regen - enough that I could drive on country roads and in the city without ever touching the brake pedal except when coming to a full stop. Something I can't do in the Leaf even in B!

Looking at the regen meter on the infotainment system energy screen, depending on road speed, D lift off regen is only about 10-15kW with B mode 30kW+, so there is quite a difference between D and B. Touching the brake pedal does give more regen in both modes though.

Limited lift off regen is a little bit disapointing but not a deal breaker for me. I'm used to it already in under a week. Ironically before switching cars I always believed the regen on the Ion was pretty weak compared to other EV's - and compared to the i3, Tesla's and Hyundai/Kia it probably is... but not compared to the Leaf 30.

On the Leaf I tend to use D mode when cruising at motorway speeds just so I can move my foot around a bit without lurching back and forth, while I use B mode driving in 30mph areas, winding country roads, down hill etc.
 

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I guess there is no ISO unit of regen with which to compare modes.
I'm sure there's a screen in the ZE menu (Energy Info?) that shows you an instant readout of power used and returned to the motor, measured in kW
 

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I'd be worried about damaging the motor in a LEAF by doing that. No doubt you can get away with it if you are lucky, and @Hitstirrer hopefully has if he's done it in one. The Ioniq and its controls are way in advance of what we LEAF owners are trusted with.
There's absolutely no danger to the car coasting in Neutral as the drive inverter is still powered up. If it was dangerous the car wouldn't let you do it.

Coasting down a hill with the car turned completely off is another matter though! :D
 

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I'm sure there's a screen in the ZE menu (Energy Info?) that shows you an instant readout of power used and returned to the motor, measured in kW
Yep press the ZE button to the bottom right of the screen then the top left option in the onscreen menu.
 

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I guess there is no ISO unit of regen with which to compare modes.
There is, an clearly kWh is the unit.
Coasting down a hill with the car turned completely off is another matter though!
Nissan don't allow towing with the front wheels on the ground in any state. Why not if just "leaving the car turned on in Neutral" is adequate?
 

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2017 Flame Red Leaf 30 Acenta
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Discussion Starter #17
Yep press the ZE button to the bottom right of the screen then the top left option in the onscreen menu.
Cheers, I didnt realise that there is a regen meter on the ZE menu. Will take a gander at it.

I cant begin to get my head around a regen mode on other EVs that is stronger than B mode on a Leaf - I feel like I'm being thrown through the windscreen when I lift off in B Mode.
 

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There is, an clearly kWh is the unit.
Indeed, however the amout of deceleration you'll get in M/S^2 depends on how heavy the car is, and whether you're going downhill or uphill so it's not a direct indicator of the sense of deceleration that can be applied between cars or all driving conditions.
Nissan don't allow towing with the front wheels on the ground in any state. Why not if just "leaving the car turned on in Neutral" is adequate?
They don't need to "allow" it because it's FWD, so it's easy to tow the car with the front wheels raised off the ground and avoid the whole situation.

The problem with them saying it was allowed is that the usual reason for a car being towed is that it has broken down or run out of charge. Clearly it can't go into neutral if the battery is flat, and even if it wasn't they can't trust the tower to make sure the car is turned on properly, handbrake and parking brake released and in neutral. And what if the battery went flat during the tow and shut down with nobody in the car to notice ?

If the battery wasn't flat and the drivetrain was working normally (and thus safe to tow in neutral) there probably wouldn't be any reason to tow it eh ? ;)

Better from a liability and warranty perspective to just say don't tow it with the front wheels on the ground. That says nothing about whether it's OK to coast in neutral for a couple of minutes, vs towing a broken down car for potentially 50+ miles.

Neutral is a software construct in an EV, nothing changes mechanically. It's the same as finding the "zero point" on the accelerator. If it was dangerous to enter neutral in motion it would be trivial to lock it out in software. The fact that they haven't says it's not dangerous as there are so many other safety interlocks in the car right down to not being able to turn the car on or engage drive without the brake pedal pressed.

Incidentally, the Ion, which is RWD, does state that towing is allowed with the driven wheels on the road - provided that speed and distance are limited and the car is turned on in ready mode. (Thus the drive inverter powered up) This is probably an acknowledgement of the fact that not all tow trucks are flat beds and towing the car backwards with the rear wheels off the ground would be dangerous. With the Leaf being FWD they can just say don't tow with the front wheels on the ground.
 

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I cant begin to get my head around a regen mode on other EVs that is stronger than B mode on a Leaf - I feel like I'm being thrown through the windscreen when I lift off in B Mode.
I think that the LEAF maxes out at 30kW, although that may be the 24.
Neutral is a software construct in an EV, nothing changes mechanically. It's the same as finding the "zero point" on the accelerator.
I can't argue against that but it's very different from the mechanically driven world. What happens to the fields created by the rotating motor - does the software match them?
 

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30KW Tekna (2017)
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Is any finding greater range in just plain old D non eco than full eco and B mode!

Englightning!

I did from 60% to 50% with 1 mile per KW, fun windscreen demise on and pouring rain today.

I was pretty happy!
 
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