LEAFfan
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Re: regen vs mechanical brakes

Sun Jun 05, 2011 12:03 am

townsat wrote:Adjustable regenerative braking. That is what every electric car should have.


I believe the VW Golf e-Motion (2014) will have adj. regen.
2013 LEAF SV Del. 2/28/13
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Herm
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Location: Timbuktu, Mali

Re: regen vs mechanical brakes

Sun Jun 05, 2011 6:12 am

LEAFfan wrote:
townsat wrote:Adjustable regenerative braking. That is what every electric car should have.

I believe the VW Golf e-Motion (2014) will have adj. regen.


Anytime you start messing with the brakes you open yourself up to suits and bad press.. not a good idea. Best way to conserve range is to drive like you had no brakes at all.

GroundLoop
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Re: regen vs mechanical brakes

Sun Jun 05, 2011 10:54 am

Herm wrote:
LEAFfan wrote:
townsat wrote:Adjustable regenerative braking. That is what every electric car should have.

I believe the VW Golf e-Motion (2014) will have adj. regen.


Anytime you start messing with the brakes you open yourself up to suits and bad press.. not a good idea. Best way to conserve range is to drive like you had no brakes at all.

I respectfully disagree.

Maximum regen doesn't mess with the brakes at all.

If the Go pedal had maximum regen, I'd hardly ever need to use the brakes while driving.
But any driver who moves his foot to the brake would get all the friction brakes on top of the 'engine drag'.

I really like the comparison to driving a big-bore stick-shift car in first gear. If you let off the gas, it's going to come to a stop pretty quick. There's no reason an EV couldn't do the same.

Herm
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Re: regen vs mechanical brakes

Sun Jun 05, 2011 11:05 am

Max regen on the go pedal would not be good for your range, you want to glide/coast on occasion and since you have no clutch then the analogy to a stick shift fails.. but then someone will suggest a button on the steering wheel that disables the regen so that you can coast.. thats where the suits to Nissan start to come in when people make a mistake. My idea: let go of the go stick and the car coasts, no regen (but people expect braking action from an auto transmission.. more suits) you step on the brakes and the car automatically blends regen and friction braking. I'm sorry lawyers that are forum members.. you need to die :)

Probably the best way is to let off the go stick a bit and the car glides, let go all the way and mild regen takes over (or strong if you prefer).. brakes still automatically blend the two types of braking. I think this is the way the Leaf works, smart people those Nissan engineers.

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gbarry42
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Re: regen vs mechanical brakes

Sun Jun 05, 2011 11:33 am

GroundLoop wrote:I really like the comparison to driving a big-bore stick-shift car in first gear. If you let off the gas, it's going to come to a stop pretty quick. There's no reason an EV couldn't do the same.
I drove a Mini-E once and it was set up this way. It was quite a surprise, but it was also apparent what to do with it. I don't think anyone's been killed using it.
Herm wrote: but then someone will suggest a button on the steering wheel that disables the regen so that you can coast..
And the EV-1 had a coast button on the stick. And people liked it. And no one died using that, either.
And there goes the first capacity bar! At 24,000 mi on 9/9/2013.
Second bar at 30,500 mi on 2/7/2015.

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johnr
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Leaf Number: 2151
Location: Exeter, CA

Re: regen vs mechanical brakes

Sun Jun 19, 2011 4:10 pm

So, if I understand correctly - the LEAF's braking system is kind of like this?

So, you can get most of the available regen without applying the friction brakes, then there's a little bit more regen available with the friction brakes lightly applied, then the rest of the way the regen continues contributing at 100% and the friction brakes handle the remainder?

Image
My trip to Mineral King and the value of regen

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2011 upgrade: Fossil < Leaf. 2014 upgrade: Leaf < imiev. 2017 upgrade: imiev < tesla. Done upgrading.

wgs1912
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Joined: Fri Oct 01, 2010 6:58 am
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Location: NW FLORDIA

Re: regen vs mechanical brakes

Mon Jul 25, 2011 6:59 pm

I think the that let go of gas= coast, tap brake=light regen, apply brake =more regen would be a nice way to adjust regen without really distubing normal driving habits.
Is it better to let people think you are stupid than open your mouth and prove it?

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planet4ever
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Leaf Number: 1537
Location: Morgan Hill, CA, south of San Jose

Re: regen vs mechanical brakes

Tue Jul 26, 2011 12:33 am

wgs1912 wrote:I think the that let go of gas= coast, tap brake=light regen, apply brake =more regen would be a nice way to adjust regen without really disturbing normal driving habits.

Really? What other cars behave like that? Everything I've ever driven before, manual or automatic transmission, hybrid or non-hybrid, applies either engine braking or regen when you take your foot off the accelerator.

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

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