tps
Posts: 1262
Joined: Sun Sep 19, 2010 7:40 pm
Delivery Date: 07 Feb 2012
Leaf Number: 18044
Location: Philadelphia, PA

Re: Leaf regen vs Prius regen

Sun May 01, 2011 6:48 pm

In my New York drive with the Hertz rental LEAF, I found the regen to be quite good for most all of my braking needs. Like the precise acceleration, the regenerative braking seemed far more precise than normal friction braking. Except at the beginning of the drive, when the battery was full, I found the regenration to be strong enough to handle just about all of my braking. (But my driving style seems to be gentler than the norm, which I think the LEAF will like when I get mine.)

IBELEAF
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Delivery Date: 06 Apr 2011
Location: Seattle, WA

Re: Leaf regen vs Prius regen

Thu May 05, 2011 10:15 am

Something I noticed while driving on ECO mode while going down the hill (about 30% grade) and let regen do the braking for you, it will be using 3 regen circles, if you press break and release it will stick to 4 regen circles. It's reproducible every time. Anyone else noticed that?
Currently: '12 Volt (12k) since 7/2012
Previously: '11 Leaf SL (w/ 12k miles & 16 month ownership)

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wsbca
Posts: 505
Joined: Tue Aug 03, 2010 4:33 pm
Delivery Date: 0- 0-2011
Location: SL-E powered by 3KW AC Solar in SoCal

Re: Leaf regen vs Prius regen

Thu May 05, 2011 10:24 am

IBELEAF wrote:Something I noticed while driving on ECO mode while going down the hill (about 30% grade) and let regen do the braking for you, it will be using 3 regen circles, if you press break and release it will stick to 4 regen circles. It's reproducible every time. Anyone else noticed that?
30% is an extremely steep hill (eg. there are only 4 roads in San Francisco over 30%). Assuming our SOC is not too high, I'm pretty sure we get 4 circles simply by letting up on the accelerator on our 10% downhill, but I'll double check to see whether one needs to 'trigger' that by touching the brake.
I was promised a jet pack!

IBELEAF
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Location: Seattle, WA

Re: Leaf regen vs Prius regen

Thu May 05, 2011 10:41 am

wsbca wrote: 30% is an extremely steep hill (eg. there are only 4 roads in San Francisco over 30%). Assuming our SOC is not too high, I'm pretty sure we get 4 circles simply by letting up on the accelerator on our 10% downhill, but I'll double check to see whether one needs to 'trigger' that by touching the brake.
Hm, maybe I' am exaggerating on the steepness %, could be 20% but it's definitely not extreme and just letting up accelerator results in 3 circles. Actually, you don't even need to be on the hill, I am reproducing this even when taking an exit on the freeway and simply breaking once and the regen sticking to 4 circles afterwards vs 3 circles if I let it coast. I'll see if non ECO mode has the same behavior.
Currently: '12 Volt (12k) since 7/2012
Previously: '11 Leaf SL (w/ 12k miles & 16 month ownership)

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abasile
Posts: 1922
Joined: Thu Sep 02, 2010 10:49 am
Delivery Date: 20 Apr 2011
Location: Arrowbear Lake, CA

Re: Leaf regen vs Prius regen

Thu May 05, 2011 11:16 am

In ECO mode when you let off on the accelerator, it seems that the amount of regen is correlated to one's speed. In other words, the car applies more regen resistance at higher speeds. That is necessary to keep the feeling of "engine braking" relatively constant, as an ICE will offer more resistance as it is spun at higher speeds. BTW, I really prefer ECO mode at all times because of the finer power control and the ability to do mostly single-pedal driving. I also like to display the Energy Info screen continuously, as I prefer more granularity than the "bubbles" offer, and I like knowing when I am truly "gliding".

As LEAF regen maxes out at 30 kW compared to ~ 20 kW in the third-generation Prius, I find that with the LEAF it is significantly easier to avoid friction braking when driving around in the mountains where we live. (Of course, it also helps that the LEAF has a far larger battery pack!)
2011 LEAF at 71K miles, pre-owned 2012 Tesla S 85 at 98K miles
LEAF battery: 9/12 bars and < 49 Ah (-28% vs. new)
Tesla battery: 250+ miles of range (-5% vs. new)

juanmax
Posts: 12
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Delivery Date: 03 Aug 2012

Re: Leaf regen vs Prius regen

Fri Aug 03, 2012 5:38 am

Hello community,

I am new here but have several years in Automotive development and hybrid-E/Cars. I am waiting for my Leaf to arrive too ;)

Just wanted to say that the amount of regen (not sure about what Nissan makes) is normally vehicle speed dependent just because of the power relation to speed. (power = torque x speed)

If the electromotor produces,lets say ,a regen torque of "-50 Nm" constantly when we lift the "gas" pedal off, then the power of our regen will vary with the speed of the vehicle. Since I "suspect" that the rings in the Leaf display are related to power, this explains why in Eco mode, at different speeds you see diferent "regens". Howere, driving is a nice sensation to have a constant regen torque, since what you feel is acceleration, and acceleration is directly proportional to torque.

This is another nice thing about E-Car, the ability to produce a "simulated drag" which is constant! Unlike an ICE which will be near zero at 1000rpm...

Sorry for my english.

Cheers.

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EVDRIVER
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Re: Leaf regen vs Prius regen

Fri Aug 03, 2012 7:07 am

juanmax wrote:Hello community,

I am new here but have several years in Automotive development and hybrid-E/Cars. I am waiting for my Leaf to arrive too ;)

Just wanted to say that the amount of regen (not sure about what Nissan makes) is normally vehicle speed dependent just because of the power relation to speed. (power = torque x speed)

If the electromotor produces,lets say ,a regen torque of "-50 Nm" constantly when we lift the "gas" pedal off, then the power of our regen will vary with the speed of the vehicle. Since I "suspect" that the rings in the Leaf display are related to power, this explains why in Eco mode, at different speeds you see diferent "regens". Howere, driving is a nice sensation to have a constant regen torque, since what you feel is acceleration, and acceleration is directly proportional to torque.

This is another nice thing about E-Car, the ability to produce a "simulated drag" which is constant! Unlike an ICE which will be near zero at 1000rpm...

Sorry for my english.

Cheers.

Yes, I was about to note that. You will also find the regen on the LEAF cuts out quickly in many cases and much power is wasted to the friction brakes.

Mx5racer
Posts: 176
Joined: Mon Oct 18, 2010 8:59 pm
Location: Yorba Linda, ca

Re: Leaf regen vs Prius regen

Fri Aug 03, 2012 9:51 pm

I feel just the opposite and wish that the Eco on my 2012 Priuswould slow it down by lifting off the gas like it does in the Leaf. With the Prius I have to move my foot to the brake pedal much more than in the Leaf.

I do wish that I could have the regen on the Leaf without the acceleration limitations.
Silver SL
Yorba Linda, CA
5.9 Solar

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planet4ever
Posts: 4674
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Delivery Date: 02 May 2011
Leaf Number: 1537
Location: Morgan Hill, CA, south of San Jose

Re: Leaf regen vs Prius regen

Sat Aug 04, 2012 12:29 am

Mx5racer wrote:I feel just the opposite and wish that the Eco on my 2012 Prius would slow it down by lifting off the gas like it does in the Leaf. With the Prius I have to move my foot to the brake pedal much more than in the Leaf.
I don't know about the 2012, but my seat-of-the-pants feel, as well as my downhill experience, tells me our 2007 Prius has more regen in "B" than the LEAF in "ECO". Well, at least until the Prius battery is full going downhill. After that you have no regen and a screaming engine.
Mx5racer wrote:I do wish that I could have the regen on the Leaf without the acceleration limitations.
Total nonsense. Push the accelerator to the floor and the LEAF jumps just as fast in "ECO" as it does in "D". There is no "limitation", only a different mapping for a partially depressed pedal.

Ray
End of April 2013: Traded my 2011 SL for a 2013 S with charge pkg.

Mx5racer
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Re: Leaf regen vs Prius regen

Sat Aug 04, 2012 6:32 am

planet4ever wrote:2007 Prius has more regen in "B" than the LEAF in "ECO".
I read on the Prius forum that B mode for the 2012 creates less regen and uses more engine braking?
planet4ever wrote: There is no "limitation", only a different mapping for a partially depressed pedal.
I know
but
I like the pedal feel better in Drive Mode.
Silver SL
Yorba Linda, CA
5.9 Solar

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