Capacity Loss on 2011-2012 LEAFs

[edatoakrun]

="surfingslovak...The NREL tear-down report dress found a while ago, has 25.41 kWh from the wall. It also recorded charging efficiencies and measured the usable energy output form a new battery at 21.38 kWh....

Has anybody ever found the temperature standard used in the NREL test?

How could you replicate that battery temperature in your own charge tests?

And these battery temperature variations would be expected to cause variations in both charging efficiency, and available battery capacity.

Should we not expect significant variation from NREL due to that uncontrolled variable, even if every "new" battery had exactly the same available capacity, and if every LEAF's BMS stopped charging at precisely the same "100%" Charge level, the percentage of that capacity allowed?

 

[LEAFer]

Regen Bubbles behaviour:

Had the same yesterday as turbo2ltr reports above. The LEAF was cold-soaked overnight outside to near freezing while sitting at 80% SOC for 17 hours when at 09:27 the OAT displayed 37F. But I suspect the OAT is somewhat inaccurate, especially in rising temperature environment, until driven (it wasn't) for several miles and time. At 09:50 (to 11:16) did TimerOverride charge to 100%. The OAT at 12:11 and 13:36 still showed 37F, while the actual was more like 50F by 12Noon. At 13:36 took off on a 44 mile drive. Even after 4 SOC bars had gone, last regen bubble was missing and the second-to-last one was intermittent. Near the end of the return portion of the 44 mile trip, the last regen bubble was occasionally intermittent. OAT at 55F at this point (matching expected actual temp), and the battery was warmer (had moved from 4TB to 5TB) from driving and ambient.

And ... I am still waiting to publish all the data ... but the GID count is pretty high at 100% :?

 

[surfingslovak]

Here are preliminary results. I estimated 2 months from manufacture to delivery. Does not include efficiency (miles per kwh from dash) or solar loading for most of the cars listed.

Great to see this! Is there a way to calculate the correlation factor between the values in columns O and P with the software you are using?

 

[KJD]

Stoaty, It looks to me like you have done some excellent work on the aging model, so do not take this wrong. I think that the accuracy of the aging model could be improved by using Manufacture date instead of purchase date.

It is my theory that the batteries start to age as soon as they are built. The Manufacture date would also show more accuracy when comparing cars that sat on the lot 1 day versus a car that sat on the lot one year. Something to think about.

Thanks again for your hard work on the wiki and the aging model.
KJD

Car -------Miles ------Manufacture
Red429 - 11,500 ----- 3/2011
Blue494 - 29,000 ----- 4/2011
Blue534 - 16,000 ----- 4/2011
White530-12,000 ----- 4/2011
White272-17,500 ----- 3/2011
Red500 - 22,500 ----- 2/2011
White626-17,300 ----- 4/2011
Blue842 -- 2,500 ----- 4/2012
Silver679-14,750 ----- 5/2011
Blue917 - 13,900 ----- 5/2011
Black782--7,000 ----- 4/2012 (San Diego)
Blue744- 22,400 ----- 4/2011
RedXXX -- 100 ------ 8/2012

Helpful, but the model uses date of purchase rather than date of manufacture. I can put in a guesstimate of 2 months from manufacture to delivery, but it would be better to have actual date of purchase, since that was used to tune the model. If you can PM me the owner names (forum handle) for each car, I can probably get most of the information from the Wiki. I have been meaning to work on the validation of the model, but haven't gotten around to it until now.

 

[Stoaty]

Here are preliminary results. I estimated 2 months from manufacture to delivery. Does not include efficiency (miles per kwh from dash) or solar loading for most of the cars listed.

Great to see this! Is there a way to calculate the correlation factor between the values in columns O and P with the software you are using?

But of course

Here is a graph with the correlation coefficient for Phoenix Leafs (I didn't include Tony's Leaf, since it lives in San Diego).

 

[TonyWilliams]

I think it reasonable to assume that this might be one of the reasons why Nissan postulates a range of ranges (76-to-84 miles), rather than just the average (80 miles), illustrated with the error bars in my chart.

I know I've asked you this more than once, and to date I don't recall a response.

How do you compensate for climate control use? You'll note that the Nissan tech data does not specify lack of climate control, and obviously that can make even a brand new car only drive, say 76 miles.

 

[Stoaty]

Here is another view of the range test data:

 

[Stoaty]

And one more view of the range test data vs Battery Aging Model Predictions:

 

[Yanquetino]

I think it reasonable to assume that this might be one of the reasons why Nissan postulates a range of ranges (76-to-84 miles), rather than just the average (80 miles), illustrated with the error bars in my chart.

I know I've asked you this more than once, and to date I don't recall a response.

How do you compensate for climate control use? You'll note that the Nissan tech data does not specify lack of climate control, and obviously that can make even a brand new car only drive, say 76 miles.

I don't think (?) that Nissan's 76-to-84 variance for 4 miles-per-kWh includes the use of climate control, since the projected ambient temperature is 70°F. If not, neither is it a factor when I plot its polynomial curve. My guess is that, if climate control were used, it would undoubtedly lower the entire scale even further, somewhat to cool the interior to, say, 60°F (72-to-80 miles?), but even moreso to heat the interior to, say, 80°F (64-to-72 miles?). You didn't use climate control during your test either, correct?

Two of Nissan's 6 Range Scenarios do use climate control, however, and thus it is already included in their base number for my chart.

 

[DesertDenizen]

More Regen bubble activity.

This is what I experienced this morning over 6 miles of driving, 3 to my yoga studio and 3 return trip. Car charged to 80%, charged an hour or so before I left. Battery temp had only 4 bars, first I have seen that in quite a while.
The numbers below indicate the number of regen bubbles NOT available. All over only 6 miles of driving.
1
2
1
2
1
2
1
0 (This was on my restart after yoga. BTW, I did side crow today!)
1
2
1

 

[TonyWilliams]

You didn't use climate control during your test either, correct?

Climate control off, yes.

 

[spooka]

I wanted to let everyone know Nissan has heard my concerns and repurchased my car Sonic, this afternoon. Thanks to everyone that had a part in helping to make this happen (especially Tony, the Tempe Twelve and MNL). In my case, Nissan listened to my concerns and agreed to help me. I publicly thank Nissan for this.

I fully support the EV market and I hope Nissan's actions with former owners like myself will help future adopters feel more at ease when considering the Leaf. As for myself, I have leased a new Leaf. I have always stated how much I love the Leaf and for me, leasing for 2 years makes a lot of sense considering current lease rates, even after my recent experience. Not owning the battery makes all the difference in the world to me.

I actually had two Leafs for almost two weeks. Not something I would have ever thought would happen.




This is my new red 2012 Leaf dubbed by my kids, "Knuckles" (in keeping with the Sonic the Hedgehog genre) sitting next to Sonic in my driveway.

Thank you again Nissan for backing your product in my case and all of you in the MNL community for your support.

Paul

 

[Yanquetino]

Very glad to hear that you and Nissan could work it out to your satisfaction, spooka.

 

[Stoaty]

I wanted to let everyone know Nissan has heard my concerns and repurchased my car Sonic, this afternoon. Thanks to everyone that had a part in helping to make this happen (especially Tony, the Tempe Twelve and MNL). In my case, Nissan listened to my concerns and agreed to help me. I publicly thank Nissan for this.

As for myself, I have leased a new Leaf. I have always stated how much I love the Leaf and for me, leasing for 2 years makes a lot of sense considering current lease rates, even after my recent experience.

Thanks for letting us know about a great outcome! Your concerns are alleviated, and Nissan keeps a Leaf customer.

 

[jlsoaz]

[...]
Thank you again Nissan for backing your product in my case and all of you in the MNL community for your support.

Paul

this is a good story to hear, and good that you saw your way clear to a new Nissan Leaf lease.

I've been thinking a lot about the important question of whether our discussing things in earnest here on this board would lead to Nissan drawing the wrong conclusions in some cases. I am very happy to have the opportunity to lease a Leaf, and impressed with Nissan as a world leader in presenting an affordable and in many ways excellent BEV. They are out in front of everyone on this.

Separately, I think they are making some serious business mistakes in how they are handling the battery degradation issue (which, in my fallible view, does exist). I think it is quite important that Nissan reconsider its overall approach the issue and make sure that it never is in a position of being against reasonable customers.

However, I think it's worth making the point to Nissan and others where and how and why and to what extent we are happy with a car and stand in support of the overall matter of a major automaker boldly and bravely making a commitment to EVs.

jl

 

[surfingslovak]

I've been thinking a lot about the important question of whether our discussing things in earnest here on this board would lead to Nissan drawing the wrong conclusions in some cases.

I believe that this board was an important catalyst on several occasions, and having an open discussion can be quite helpful sometimes. I have to agree that the forum might not always strike the best tone, but the discussions here are typically both civil and informed. Yes, things got quite emotional this summer, but I think that should understandable, given the context.

Thank you again Nissan for backing your product in my case and all of you in the MNL community for your support.

Glad to see this outcome, and happy to hear that Nissan was able to keep you as a customer, Paul. I'm really impressed by the EV community in Phoenix, and I hope that Nissan and other OEMs will see it as an important market, which deserves to be approached thoughtfully.

 

[jlsoaz]

I don't believe his remarks were worth much and herein lies the problem: Andy wasn't observing AZ drivers, but most likely using CarWings which is as much as a joke as the GOM. He has received so much erroneous info from CarWings which makes his 'observation of AZ drivers' useless and non-factual. The figure of 12K average for AZ drivers from the insurance companies is much more accurate and realistic.

Having had a day to think about this:

Isn't it possible that Nissan was simply reading Odometer data from the 400 vehicles which have given their permission. Even if the permissions were inconsistent, could be it be that difficult to get accurate odometer data from a vehicle?

 

[TonyWilliams]

I wanted to let everyone know Nissan has heard my concerns and repurchased my car Sonic, this afternoon. Thanks to everyone that had a part in helping to make this happen (especially Tony, the Tempe Twelve and MNL). In my case, Nissan listened to my concerns and agreed to help me. I publicly thank Nissan for this....
Paul

Congrats and thank you. I have recommended to every single person who got their Tempe Twelve car returned that a Nissan LEAF, with a cheap cost short term lease, was likely STILL the best value, assuming a large range reduction was acceptable. I hope it works out for you.

That's 6 of the 12 cars tested gone, included mine, which was traded in (I never asked Nissan for anything from my car, including the damage it sustained at the Sept 15 test).

The test is now complete, but the mission goes on.

 

[jspearman]

I wanted to let everyone know Nissan has heard my concerns and repurchased my car Sonic, this afternoon. Thanks to everyone that had a part in helping to make this happen (especially Tony, the Tempe Twelve and MNL). In my case, Nissan listened to my concerns and agreed to help me. I publicly thank Nissan for this.

As for myself, I have leased a new Leaf. I have always stated how much I love the Leaf and for me, leasing for 2 years makes a lot of sense considering current lease rates, even after my recent experience.

Thanks for letting us know about a great outcome! Your concerns are alleviated, and Nissan keeps a Leaf customer.

This is great news. I'm still waiting on Nissan, so hopefully we'll get some good news, too. I told them that we would be happy to move to a 2-year lease, but no deal so far. Meanwhile, I drove from 100% to LBW on Saturday with AC off and only made 49 miles. I'm not happy, but I wait.

 

[pb1]

Hello! Just wanted to share that Nissan responded to my concerns on the reduced range and purchased the Leaf. Lot of paperwork signed to make it happen through their third party including disclaimers about this being done for my satisfaction and not due to acceptance of any defect.

An expensive experiment for us despite a well worth year of use as this was Not a full refund but better than a trade in value. Disappointed that there was no good fix like adding TM or replace battery as we really got used to the car. Not easy to find a dependable replacement now to meet our needs and may have wait for a newer model with thermal management or something else like the Rav4 in future. Going back to gas burner for the interim.

Will keep an eye on this forum and wish luck to those struggling through range issues for a good resolution.

Thank the forum members for sharing their experiences and knowledge.