Capacity Loss on 2011-2012 LEAFs

[opossum]

We got our car back today. It appears as though they resolved the diminishing capacity issue! I took a picture of the dash. Look, they simply tricked the car into thinking it is only 80 degrees today!



But in reality, the Weather Channel app says it was 108!



That should help fool the batteries into holding up better! Note: I took the pictures at about 4:30pm. It seems they rolled back the clock by an hour, maybe to erase an hour of capacity loss.

Okay, in all seriousness... they must have reset things a time or two. Now that weird cabin chime is back at power-up and power-down. More importantly, the car is still missing 2 capacity bars. The car had just 8 SOC bars when I picked it up. We're told that Nissan will not have anything to share on the testing they conducted for 2 to 3 weeks. The only specific we were given was that our car tested out at 85% capacity remaining, which was 2nd best of the cars they had. The best was supposedly 86%. This makes no sense to us, as it does not agree with our real world range loss from a year ago under similar driving conditions. In all, they put 34 miles on the odometer from the time the tow truck picked it up at our house to the time I picked it up at the dealership today.

[edatoakrun]

The three periods following a statement is known as an Ellipsis.

This article may help you to understand it's meaning, in the context of my statement, that you have quoted below.

http://en.wikipedia.org/wiki/Ellipsis" onclick="window.open(this.href);return false;

[
I think you have damaged your own credibility, with your 7/30 edit to your post starting this thread:

Damaged credibility? Really From someone making wacky statements such as these?

I also want to point out, again , that by extrapolating current of US Southwest temperature trends over the last two years, the same way many have extrapolated Battery bar disappearance on this thread, could also lead to the conclusion that much of this region would be largely uninhabitable by humans during them "expected" lifespan of a 2012 LEAF battery pack.

If I lived in Phoenix, I might be much more worried about my home's future resale value, than my LEAF's...

A 2012 LEAF battery pack is going to last longer than the millions of homes in metro Phoenix, which will somehow by "uninhabitable by humans" in the near future?

There is a HUGE difference between maximum battery life and losing 30% driving range in just over a year.

You are 3 months late trying to blame the users of these 48 (reported to the forum) cars for the issues they are seeing. It's been tried, and most of these kind folks quickly realized that there is no apparent correlation to loss of bars and behavior. From what I've seen, there may be a connection between the severity/speed of the loss and usage behavior, but there's no way to tell, and there's no reason to speculate. All of the affected drivers that we personally know (9, I think) have done NOTHING that was said not to do in the warranty book, nor the owners manual, and thus there's no reason to adjust our expectations of the performance of our vehicle. Most of these owners have had EVs in their garages for decades.

What we have done is put in many, many hours trying to alert Nissan to what is obviously an issue in consistently hot climates and to help all owners get what we paid for. You're welcome!

If only we could idiot-proof the forum.

+1 and well said.

[DaveinOlyWA]

We got our car back today. It appears as though they resolved the diminishing capacity issue! I took a picture of the dash. Look, they simply tricked the car into thinking it is only 80 degrees today!



But in reality, the Weather Channel app says it was 108!



That should help fool the batteries into holding up better! Note: I took the pictures at about 4:30pm. It seems they rolled back the clock by an hour, maybe to erase an hour of capacity loss.

Okay, in all seriousness... they must have reset things a time or two. Now that weird cabin chime is back at power-up and power-down. More importantly, the car is still missing 2 capacity bars. The car had just 8 SOC bars when I picked it up. We're told that Nissan will not have anything to share on the testing they conducted for 2 to 3 weeks. The only specific we were given was that our car tested out at 85% capacity remaining, which was 2nd best of the cars they had. The best was supposedly 86%. This makes no sense to us, as it does not agree with our real world range loss from a year ago under similar driving conditions. In all, they put 34 miles on the odometer from the time the tow truck picked it up at our house to the time I picked it up at the dealership today.

i told you that 3 weeks ago. i would pay more attention to when the first modules come off the line in TN

[RegGuheert]

Thanks for the update!

The only specific we were given was that our car tested out at 85% capacity remaining, which was 2nd best of the cars they had. The best was supposedly 86%. This makes no sense to us, as it does not agree with our real world range loss from a year ago under similar driving conditions.

My guess is that they directly tested the capacity of your battery using a special-purpose tester. What's interesting is that they yielded a capacity of 85% while your car is reporting a capacity of 78.75%. This lends credence to the idea that the BMS somehow further restricts access to battery capacity in hot conditions.

[jspearman]

Thanks for the update!

The only specific we were given was that our car tested out at 85% capacity remaining, which was 2nd best of the cars they had. The best was supposedly 86%. This makes no sense to us, as it does not agree with our real world range loss from a year ago under similar driving conditions.

My guess is that they directly tested the capacity of your battery using a special-purpose tester. What's interesting is that they yielded a capacity of 85% while your car is reporting a capacity of 78.75%. This lends credence to the idea that the BMS somehow further restricts access to battery capacity in hot conditions.

The plot thickens. Curious to see what they tell us in three weeks. I concur that our real-world range is total crap now and wouldn't correspond to a 10 or 15% loss, but perhaps there is a perfectly logical explanation. Anecdotally, my wife's commute is 25 miles (half surface streets, half highway). That trip took 4 bars from the middle of September to around March. Now 7 bars are missing when she returns home. Same exact commute, same driver, same driving style. Extra A/C use would account for a small portion of that, since it's hotter now than it is in September, but September was quite hot this past year, so the difference is probably negligible.

[LEAFfan]

If one of the answers you get, is if you wanted maximum battery life from your LEAF, you should have followed the guidelines for battery care, will you like that answer?

Yes, I'm sure that all questions will be answered, and every LEAF owner will all be completely satisfied with the answers.

Nissan will announce "improvements" to the LEAF, including reduced access to the battery capacity, a battery cooling system requiring plugging into a public L2 whenever you park outside your garage on a warm day, (hey it's all free power, right?) and a "back-up" ICE, for those who cant figure out what the range of their BEV is.

The improved idiot-proof LEAF!

There is a HUGE difference between maximum battery life and losing 30% driving range in just over a year.

You are 3 months late trying to blame the users of these 48 (reported to the forum) cars for the issues they are seeing. It's been tried, and most of these kind folks quickly realized that there is no apparent correlation to loss of bars and behavior. From what I've seen, there may be a connection between the severity/speed of the loss and usage behavior, but there's no way to tell, and there's no reason to speculate. All of the affected drivers that we personally know (9, I think) have done NOTHING that was said not to do in the warranty book, nor the owners manual, and thus there's no reason to adjust our expectations of the performance of our vehicle. Most of these owners have had EVs in their garages for decades.

What we have done is put in many, many hours trying to alert Nissan to what is obviously an issue in consistently hot climates and to help all owners get what we paid for. You're welcome!

If only we could idiot-proof the forum.

+10! Well said!

[TurboFroggy]

There's an obvious contradiction here. According to the transcript above, Eric from Nissan said that the normal temperature range is within the blue and red ranges. But on the other hand, you're not supposed to keep the battery at the 120C level for more than 24 hrs. Well, 7 bars is between 98.2C to 122C, so if the temperature bar says 122C is normal, why can't the battery be under warranty at 120C for 24 hrs, if up to 135C (top range of 10 bars) is considered "normal" since it's not in the red?

Segments Degrees C (F)
12 60 (140)
11 57.5 (135.5)
10 55 (131)
9 52.5 (126.5)
8 50 (122)
7 36.8 (98.2)
6 23.5 (74.3)
5 10.3 (50.5)
4 -3 (26.6)
3 -6 (21.2
2 -9 (15.8)
1 -12 (10.4)
0 -15 (5)

Yes, I had the same thoughts about that... "between the blue and red gauge squares" essentially means we could safely charge our batteries anywhere from 15.8 degrees F to 135.5 degrees F.

The manual clear states ambient temperature, not battery temperature.

"Do not expose a vehicle to ambient
temperatures above 120F (49C) for
over 24 hours."

Page EV-2 : http://www.nissanusa.com/content/dam/ni ... manual.pdf" onclick="window.open(this.href);return false;

The reason for that is the diffrence in temps will cause the pack to cool down. Even at 120F ambient the pack can cool down to 120F which is 7-8 bars.

[mark1313]

Smiley just like mine..Losing the first one was not unexpected but losing the 2nd one with-in 40 days made me very upset...Now when I start up the car,the first thing I do is check the capacity bars

Please move me from the 1-bar club to the 2-bar club on the Wiki. Unfortunately, I lost my second bar today, after only 11 months of ownership. Lost the first bar on 6/17 at 13,745 Miles; Lost the second on 8/6 at 15,868 miles. The second bar was lost in under 2 months and 2123 miles.

I'm hoping we get some solution where we get a better battery, somehow. I enjoy driving the car and really like the electric car experience; It's just not acceptable to lose that much capacity in under a year. It is already becoming less of a useful car in our family, as we now have to include in time for charging where we didn't have to before, for some recent trips.

[KJD]

We got our car back today. It appears as though they resolved the diminishing capacity issue! I took a picture of the dash. Look, they simply tricked the car into thinking it is only 80 degrees today!

What if they kept your car in a cold room for a week and then measured the capacity. The temp gauge still has not warmed up to ambient temp at your house.

[dusty2050]

For those who might be interested.
I have started building a add on which in phase one will cool the battery while parked in the garage. It will not interfere with the cars warranty. The device consists of four liquid cooling pads which go between the current battery dust cover and the battery itself. There is a layer of foam insulation between the cool pads and the dust cover and the outside tempature. The cool pads (will not disclose at this time what they are made of) are held in place by the presure of the dust cover bolted back in place. None of the add on is permanentlly mounted to the car. The entire cool pad set can be removed as quickly as it takes to remove the dust cover and put it back. If the cool pads worst to leak, the liquid would flow down and just drip on the garage floor. There is no danger to the battery pack whatsoever. The cool packs are connected in series via two lines to a unit which chills the anifreeze mixture to a chilling 32 degress. The very large mass of the battery pack and the fact that there can't be any cool packs on the top of the battery case will mean that more than likely the system will not be able to cool the pack itself down to 32 degress. In fact the goal is to maintain the battery while connected at 72 degrees. While keeping power consumption as low as possible. One thing in the systems favor is the fact the battery modules are in the battery case very tightly and therefore actually form a single mass which can be cooled from the outside. (We already have a member that has successfully cooled his battery pack down to 72 degrees by using a window AC directing the cool air under the car while the outside tematures where well into the hundreds!) The unit does have a thermostat and if it is luckly enough to get it to the target tempature then it would shut off until needed again. If the system is found capable of bringing the tempature down to the 4 bar mark. Then the idea would be to bring it close to 4 bars and then due to its great mass it would sort of store some of the cold and would warm up slower, therefore shorting the time that the pack is at a higher tempature once disconnected and driven. This is of course if the system works as expected. Currenly the testing system is too large to be placed in the car for having an actual BMS. The plan is to eventually build a small system that can some how be added to the car in a way that does not distract from its function or interfere with the cars warranty. Of course to have the system be a true BMS system then some work would have to be done to have cooling on top of the battery which would cause some questions. But hey what do we have to loose. Even if Nissan is going to commit some research into a BMS when would we see it???

I am writting this to see if successful would any current leaf owners be interested in such a device. If so what would be a fair price for the add on. I myself do not plan on just sitting idle while my $40,000 investment turns into a paper weight!!!!

I am a software engineer by trade and I spent 20 years in the US Air Force with the last few years in an electrical engineer capacity. I believe I can build the deivce as long as I can come up with the needed funds.

Anyway I would love feedback comments and suggestions. Also I welcome questions on the idea. I will post photos of the system as it is being built but will hold some of the exact details confidential at the moment.

This of course is just thinking out loud and the information is provided as is where is and is not intended to suggest anything :>)