Significant and Sudden loss of range

[coach81]

Would love to hear from some of the others on this thread.. has your situation improved, has Nissan been able to explain/fix your lost bars??? What is the latest on the Ariz.. situation(s)?

 

[Stoaty]

Would love to hear from some of the others on this thread.. has your situation improved, has Nissan been able to explain/fix your lost bars??? What is the latest on the Ariz.. situation(s)?

Everything we know, and everything Nissan has done (not much) is in the Wiki:

http://www.mynissanleaf.com/wiki/index.php?title=Battery_Capacity_Loss#Real_World_Battery_Capacity_Losses" onclick="window.open(this.href);return false;

 

[TomT]

I borrowed a Gid Meter this week to check my car. A 100% charge brought 237 Gids which means I am at about 84 percent capacity, or about a 16 percent loss in 22,000 miles and 18 months. I suspect that the hot weather and high long-term ambient we have had here the previous few weeks has accelerated that loss... I normally very rarely charge to 100 percent, by the way, though I am finding, due to the capacity reduction, I have to somewhat more often these days to get the range I occasionally need...

 

[mdh]

I borrowed a Gid Meter this week to check my car. A 100% charge brought 237 Gids which means I am at about 84 percent capacity, or about a 16 percent loss in 22,000 miles and 18 months. I suspect that the hot weather and high long-term ambient we have had here the previous few weeks has accelerated that loss... I normally very rarely charge to 100 percent, by the way, though I am finding, due to the capacity reduction, I have to somewhat more often these days to get the range I occasionally need...

I am wondering/hoping that a major portion of your loss is temporary and it is just the battery protecting itself?

 

[DaveinOlyWA]

I borrowed a Gid Meter this week to check my car. A 100% charge brought 237 Gids which means I am at about 84 percent capacity, or about a 16 percent loss in 22,000 miles and 18 months. I suspect that the hot weather and high long-term ambient we have had here the previous few weeks has accelerated that loss... I normally very rarely charge to 100 percent, by the way, though I am finding, due to the capacity reduction, I have to somewhat more often these days to get the range I occasionally need...

if you only took one reading i would have to say your real permanent loss is closer to 88-90%. my GID count over the past week keeping in mind temps while changing ranged from upper 90's to low 60's

8/25; 277
8/23; 271
8/21; 272
8/20; 267
8/19; 265
8/18; 267
8/17; 263

 

[Stoaty]

if you only took one reading i would have to say your real permanent loss is closer to 88-90%. my GID count over the past week keeping in mind temps while changing ranged from upper 90's to low 60's

Well, since he lost a capacity bar already, Nissan thinks he has lost 15%.

 

[DaveinOlyWA]

if you only took one reading i would have to say your real permanent loss is closer to 88-90%. my GID count over the past week keeping in mind temps while changing ranged from upper 90's to low 60's

Well, since he lost a capacity bar already, Nissan thinks he has lost 15%.

OHHH!!!! i C!!! so now the consensus is bar gone, bar gone for good?

sorry missed that memo

BUT, he just went thru a few weeks of much higher than normal temps. rarely if ever charges to 100% and we are thinking his one time GID measurement is a true indication of his battery status?

all that could be true.

 

[Stoaty]

OHHH!!!! i C!!! so now the consensus is bar gone, bar gone for good?

We have a couple of reports of "bar wobbling"; the owners lost the bar for good after a short time. Only other report is capacity bars reset by Nissan. That bar disappeared again shortly after that. There aren't any reports from people who lost a bar, regained that bar and the bar stayed for months at a time. That's enough info for me (for now). Of course, if we start getting a bunch of reports as the weather cools down that capacity bars are coming back, that would be a different story. If there was even the smallest likelihood of that happening, I believe Nissan would have been all over it when responding to the capacity bar loss issue.

 

[TomT]

I've already lost the first capacity tick so it clearly is more than 10 to 12 percent... I actually took three readings that were all within one Gid of each other... The temperatures when I charged and took my readings were post heatwave and back to the mid 70s...

if you only took one reading i would have to say your real permanent loss is closer to 88-90%. my GID count over the past week keeping in mind temps while changing ranged from upper 90's to low 60's

 

[DaveinOlyWA]

OHHH!!!! i C!!! so now the consensus is bar gone, bar gone for good?

We have a couple of reports of "bar wobbling"; the owners lost the bar for good after a short time. Only other report is capacity bars reset by Nissan. That bar disappeared again shortly after that. There aren't any reports from people who lost a bar, regained that bar and the bar stayed for months at a time. That's enough info for me (for now). Of course, if we start getting a bunch of reports as the weather cools down that capacity bars are coming back, that would be a different story. If there was even the smallest likelihood of that happening, I believe Nissan would have been all over it when responding to the capacity bar loss issue.

i understand all that and since nearly no part of the country has experienced a major temperature change since it is still Summer for most, you are correct in that no one has seen this.

but my statement was "i believe" and permanent loss (as opposed to observable loss which is temperature dependent) would be...

it was meant to not be definitive and is based on observations and a limited experiment on my LEAF.

now, with only one car to use and now looking like we might not have another good opp to verify any numbers, its a bit of a stretch to say this and that.

but the experiment, with a few surprises, did exactly what i thought it would do.

i purposefully charged the car at temps up to 40º warmer than normal and lost capacity. capacity that was gone for more than 4 days after i started back to charging at a lower ambient temperature (personally i got a bit nervous when my GID count dropped to 263 the day AFTER the weather cooled off...)

so if you add in the start of the experiment, its almost two weeks i showed degradation of as much as 6.5% with most of the readings running just over 5%.

now i am at 1.5% which is actually higher than the start of the experiment.

you see, before i started, i wanted to make sure that the pack was balanced, yada yada. so i charged to 100% 6 days in a row. 3@275, 3@276 1 @ 277

but the immediate impact on a relatively small increase in temps (to the mid 80's) was a GID count that dropped to 267ish.

now, there is a bit of a parallel experiment going with a Portland OR LEAF driver who experienced near identical GID loss that i did during our very hot period recently. as mine did, his is slowly regaining the charge lost. now he has not progressed as much as i have but realize this morning's 277 is 5-6 GID higher

i have posted some thoughts on my blog but the real thing we need to do is

stop jumping to conclusions
wait for some more data

 

[druidz6]

I realized that I had not explained what eventually happened when the corporate team took my car.

They found a bad battery module and replaced it. Since then everything has been working great -- no sign of the problem at all. The interesting thing, however, is that the problem was not found using the standard diagnostics the dealer was using. Rather, the corporate team contacted me, came to my home, took the car, left a loaner and returned it fixed about 10 days later. The dealer, who was about to call in the corporate team, said that they showed up independently though he had sent them an email.

Moral here (and I think someone else on these forums has made this point), is that at least Nissan dealers don't have all of the tools necessary to detect this problem. A module can fail in the way it did for me, and they won't see it. I think that Nissan should be able to build these kinds of diagnostics into the car.

 

[EdmondLeaf]

Thank you for update, very interesting

 

[Luft]

The interesting thing, however, is that the problem was not found using the standard diagnostics the dealer was using.

This is more than interesting, it's major. It is unacceptable that we can have a sudden capacity loss that can not be diagnosed by any Nissan dealership.

 

[Boomer23]

The interesting thing, however, is that the problem was not found using the standard diagnostics the dealer was using.

This is more than interesting, it's major. It is unacceptable that we can have a sudden capacity loss that can not be diagnosed by any Nissan dealership.

+1

Any LEAF owner who experiences a similar failure shouldn't have to face the experience of having to arrange Nissan corporate engineers talking to their dealer service people. Seems to me that a module failure should be job 1 for EV diagnostic systems.

 

[RegGuheert]

It is unacceptable that we can have a sudden capacity loss that can not be diagnosed by any Nissan dealership.

I think they have the proper tools to detect a failed module, but they will ONLY detect it if they do the cell voltage loss test properly. I've read a couple of stories on here where they have done the test at a high SOC, which will NOT detect a failed module.

 

[mwalsh]

+1

Any LEAF owner who experiences a similar failure shouldn't have to face the experience of having to arrange Nissan corporate engineers talking to their dealer service people. Seems to me that a module failure should be job 1 for EV diagnostic systems.

+2. Makes you suspicious of the whole process! :x

 

[DaveEV]

It is unacceptable that we can have a sudden capacity loss that can not be diagnosed by any Nissan dealership.

I think they have the proper tools to detect a failed module, but they will ONLY detect it if they do the cell voltage loss test properly. I've read a couple of stories on here where they have done the test at a high SOC, which will NOT detect a failed module.

While that is true, one would think that the car would also track the estimated capacity of each of the 96 cell-pair using voltage information, and throw the appropriate error code when a weak cell-pair is found.

This really shouldn't be something that needs to be diagnosed using a Consult - the in-car BMS should automatically detect these situations, especially when one runs into a situation where one cell-pair is so much weaker that it noticeably affects range.

If a cell-pair's voltage reads significantly different from the others at any time, it should trigger an error code identifying which module has the weak cell-pair. Simple as that!

 

[DaveinOlyWA]

The interesting thing, however, is that the problem was not found using the standard diagnostics the dealer was using.

This is more than interesting, it's major. It is unacceptable that we can have a sudden capacity loss that can not be diagnosed by any Nissan dealership.

it is but but nevertheless common when new technology was released. Ford and Toyota dealerships had similar issues with the Prius and the Escape and Fusion Hybrids.

we dont remember them now because the cars were successful but in the early days, corporate tech hot shots earned a lot of miles

 

[vegastar]

Here in Portugal I know 2 cases of Leafs with sudden loss of range where Nissan Iberia, not the dealers, called the owners. They said the problem was detected via Carwings.

In this case the entire battery was replaced:

http://www.nissanleafpt.com/viewtopic.php?f=49&t=3092