SageBrush
Posts: 1482
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Delivery Date: 13 Feb 2017
Location: Colorado

Re: Battery temp management for new leaf

Mon Sep 18, 2017 8:18 am

BuckMkII wrote:I'm doubtful of the usefulness of this with user-reported range (not based on a consistent, controlled protocol) instead of some internally measured parameters that would be more consistent from car to car.

The owners are reporting from a kWh meter equivalent and not a LEAF type GOM. Driving behavior and conditions do not affect the result. See my post above

If you like you can confirm this with the author of LeafSpy and TM-Spy Turbo3 although there really is not anything to doubt.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

lorenfb
Posts: 1405
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Battery temp management for new leaf

Mon Sep 18, 2017 9:21 am

SageBrush wrote:
BuckMkII wrote:I'm doubtful of the usefulness of this with user-reported range (not based on a consistent, controlled protocol) instead of some internally measured parameters that would be more consistent from car to car.

The owners are reporting from a kWh meter equivalent and not a LEAF type GOM. Driving behavior and conditions do not affect the result. See my post above

If you like you can confirm this with the author of LeafSpy and TM-Spy Turbo3 although there really is not anything to doubt.


Are you indicating that the graphical data previously posted results from TM-Spy app data? If I'm not mistaken,
that Tesla app is less than a year old in a released (non-beta) form, right?

SageBrush
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Location: Colorado

Re: Battery temp management for new leaf

Mon Sep 18, 2017 9:37 am

lorenfb wrote:Are you indicating that the graphical data previously posted results from TM-Spy app data?

No

I'm saying that TM-spy collaborates the car's rated miles (RM) display. As it obviously should since RM is simply kWh*K where K is a constant representing the EPA combined cycle consumption rate.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

edatoakrun
Posts: 4745
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Delivery Date: 15 May 2011
Leaf Number: 2184
Location: Shasta County, North California

Re: Battery temp management for new leaf

Mon Sep 18, 2017 10:17 am

Can you folks take your endless, boring, off-topic comments to another thread?

Back on topic:

I saw no evidence at either of the LEAF intro events I attended of any change in temperature management in the "40 kWh" pack, and heard no hint of any changes planned for the "60 kWh" pack, when introduced.

So, both versions to have sealed packs with conductive cooling, just like all the earlier LEAFs?

Anyone seen or heard anything different?

edatoakrun wrote:
GetOffYourGas wrote:
DaveinOlyWA wrote:With an expected increase in chademo speed as well. Hard to believe otherwise. The real question becomes can they do it all and keep the price down? Its my thinking that is the reason they have not already come out with it. They want to maintain that $30-35K price range or at least near that.

This is my thinking. But it's based more on hope and wishful thinking than any kind of hard facts.

It would have been an odd decision, IMO to add either liquid cooling or pack insulation to the 2018 LEAF.

Even more bizarre, would be to add it to only some of (the likely lower production volume, higher capacity pack versions) the 2019 LEAFs.

Adding either feature is relatively trivial from an engineering standpoint, though very expensive in terms of production cost and efficiency.

If Nissan saw any benefit, why did it not add either or both features to the 2018 MY?

So, while anything is possible, until a high integrity source reports otherwise, I think we should expect Nissan to retain passive thermal management, primarily utilizing conductive cooling, in all 2019 MY LEAFs.

Either or both pack designs could use suppplementary active air cooling, much as some other BEV manufactures have, which is very low cost, but provides minimal benefits in terms of reducing battery temperature.

I'd regard blowing air from the standard AC system over the cell cases as mainly a placebo for those suffering from capacity loss anxiety, but it would allow Nissan to tout this benefit, to those misinformed buyers for which it could be appealing.
no condition is permanent

lorenfb
Posts: 1405
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Battery temp management for new leaf

Mon Sep 18, 2017 10:39 am

SageBrush wrote:
lorenfb wrote:Are you indicating that the graphical data previously posted results from TM-Spy app data?

No

I'm saying that TM-spy collaborates the car's rated miles (RM) display. As it obviously should since RM is simply kWh*K where K is a constant representing the EPA combined cycle consumption rate.


So what! It just reads the same BMS ECU data. As previously mentioned, without a controlled longitudinal study,
e.g. a linear regression, anecdotal data and resulting conclusions are of little value.

GetOffYourGas
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Location: Syracuse, NY

Re: Battery temp management for new leaf

Mon Sep 18, 2017 10:50 am

edatoakrun wrote:Can you folks take your endless, boring, off-topic comments to another thread?

Back on topic:

I saw no evidence at either of the LEAF intro events I attended of any change in temperature management in the "40 kWh" pack, and heard no hint of any changes planned for the "60 kWh" pack, when introduced.

So, both versions to have sealed packs with conductive cooling, just like all the earlier LEAFs?

Anyone seen or heard anything different?


I have heard nothing official from Nissan. Plenty of speculation, though. I wouldn't be surprised if the former AESC will still produce the 60kWh battery, and not LG Chem. LG has a great battery, but it requires TMS. AESC has a less great battery (but still great IMO, all things considered) which doesn't require a TMS, at least in moderate climates. Yes this point is arguable, and has been argued ad nauseum. But the fact is, LG's battery is more volatile and would not survive anywhere near as well as AESC's without TMS.

Maybe Nissan needs another year because they are waiting on AESC to produce. Just more speculation, of course. But again, I have seen nothing more than a few journalists claiming that the 60kWh battery will be from LG, let alone that it will have TMS.
~Brian

EV Fleet:
2011 Torqeedo Travel 1003 electric outboard on a 22' sailboat
2012 Leaf SV (traded for Bolt)
2015 C-Max Energi (302A package)
2017 Bolt Premier

SageBrush
Posts: 1482
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Delivery Date: 13 Feb 2017
Location: Colorado

Re: Battery temp management for new leaf

Mon Sep 18, 2017 11:05 am

lorenfb wrote:
SageBrush wrote:
lorenfb wrote:Are you indicating that the graphical data previously posted results from TM-Spy app data?

No

I'm saying that TM-spy collaborates the car's rated miles (RM) display. As it obviously should since RM is simply kWh*K where K is a constant representing the EPA combined cycle consumption rate.


So what! It just reads the same BMS ECU data.

Indeed it does. The data has the exact same utility had a large group of LEAF owners supplied their car Ahr battery capacities when charged to full in addition to the age of their cars and the odometer reading. Like this:

Image

The Tesla data however is on the internet in Google Doc format if you care to crunch it another way. I don't see the utility, but you could certainly collect all the cars that have provided more than one data point and display a "longitudinal" distribution of range loss per time or a longitudinal distribution of range loss per 10k miles. Regardless, the battery data as is says the Tesla has phenomenal longevity, while the Nissan battery ... pretty much sucks
Last edited by SageBrush on Mon Sep 18, 2017 3:33 pm, edited 3 times in total.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

Dooglas
Posts: 176
Joined: Thu Apr 03, 2014 10:08 pm
Delivery Date: 04 Jan 2017
Leaf Number: 314779
Location: Oregon City, OR

Re: Battery temp management for new leaf

Mon Sep 18, 2017 1:45 pm

SageBrush wrote:The data is on the internet in Google Doc format if you care to crunch it another way. I don't see the utility, but you could certainly collect all the cars that have provided more than one data point and display a distribution of range loss per time. Regardless, the battery data as is says the Tesla has phenomenal longevity, while the Nissan battery ... pretty much sucks


What happens when the data are portioned into vehicles built 3/13 and earlier versus vehicles built 4/13 and later? I presume you would see the utility of doing that.
Last edited by Dooglas on Wed Sep 20, 2017 3:12 pm, edited 2 times in total.
2013 Leaf SV - lease ended, 2016 Leaf S30

SageBrush
Posts: 1482
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Battery temp management for new leaf

Mon Sep 18, 2017 3:26 pm

Dooglas wrote:
SageBrush wrote:The data is on the internet in Google Doc format if you care to crunch it another way. I don't see the utility, but you could certainly collect all the cars that have provided more than one data point and display a distribution of range loss per time. Regardless, the battery data as is says the Tesla has phenomenal longevity, while the Nissan battery ... pretty much sucks


What happens when the data are portioned into vehicles built 3/13 and earlier versus vehicles built 4/13 and later?

The raw LEAF data (as shown in the post above) is not available for other types of analysis. My comment to Lorenfb was talking about the Tesla owner battery data available on the web in Google Doc.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

Joe6pack
Posts: 76
Joined: Tue Oct 09, 2012 4:57 pm
Delivery Date: 07 Oct 2012
Leaf Number: 025854

Re: Battery temp management for new leaf

Mon Sep 18, 2017 4:47 pm

So the Tesla data is the reading on the Tesla's GOM after a full charge at startup. That number is then compared to the theoretical EPA range of the car to derive the % degradation. This would be the same as taking the reading from the LEAF's GOM after a full charge and comparing that to its theoretical EPA range which we all know would be bogus. This is not the same thing as reading the remaining capacity in AHrs directly from the BMS. It also explains why so many cars have negative degradation.
2012 Leaf SL leased October 4th, 2012
Braselton, GA

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