Capacity Loss on 2011-2012 LEAFs

surfingslovak said:

DaveinOlyWA said:

all of it plays a part. as to the degree i would rate them from worst to best

1) heat
2) time
3) charge cycles

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[text deleted]

Please keep in mind that I did not have access to permanent degradation figures. Gids are a simple stored capacity reading, and although they give us an idea of how much capacity the battery might have lost, it's not a 1:1 relationship. That said, I calculated the following correlation factors:

Code:

Gids/Miles:          -8.61%
Gids/Vehicle Age:   -13.58%
Gids/Ambient Temp:  -55.56%

This means that vehicle age contributes about twice as much as mileage. In another words, you would expect a one-year-old Leaf with 24 K miles to have about the same level of capacity loss as a two-year-old Leaf with 12 K miles. The higher mileage car would have twice as many full charge cycles. Mileage and charge cycles should be interchangeable in this context.

Although I excluded the Arizona Leafs from the calculation, it's pretty obvious that average ambient temperature seems to have an overwhelming effect. In the small sample I evaluated, it contributed twice as much as vehicle age and mileage combined.

We can only guess, but this could be an expression of the seasonality, which was observed earlier. Still, this is another indication that ambient temperature matters, and has a very noticeable impact on Gid counts.

Click to expand...

Nicely done, slovak. Thanks for teasing this out of the limited data. Many factors, weighted towards amb temperature. I'm on board with this theory, which excluded samples in the AZ/TX/other 100+°F areas. Behavior in those areas may represent a more downward sloping portion of the same degradation 'curve' (gids vs amb t). Or above some temperature, a separate curve altogether (to include effects of currently unavailable permanent degradation figures).

edatoakrun said:

Please attribute all quotes, and post a link to the source, for context.

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Dude, I have much better things to do with my time than dig through hundreds of posts to find references to the various topics that have been discussed already.

edatoakrun said:

IMO, it is fairly certain that the factors that we all expected to lead to more rapid capacity degradation, battery temperature, amount of use of the high and low end of battery capacity, and amount of time spent at high and low charge level, are all now showing up in loss of capacity bars, and gid/SOC reports.

Click to expand...

Sorry, but no. Based on the details in the 220+ pages of this thread and all the LEAF owners I've spoken to here in Phoenix, it is blatantly obvious to me that you are giving too much weight to factors that are far less significant, like "amount of time spent at high and low charge level." I could go back and reference the various examples of people who were poster children for LEAF battery care and yet have/had lost over 15% in roughly the same time/miles. But again, I'm a busy person, and doing that would be one of the least useful ways to spend my time.

Our cars should come back from Casa Grande sometime tomorrow. I am REALLY looking forward to some answers from Nissan that hopefully put all of this forum speculation to bed!

opossum said:

... I am REALLY looking forward to some answers from Nissan that hopefully put all of this forum speculation to bed!

Click to expand...

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!

Sounds a lot like a Volt, doesn't it?

And looking back on the thousands of comments on this topic, maybe GM does understand the American driver, much better than Nissan does...

I thought I would add this into the discussion about capacity loss and the deceleration that Nissan claims should be happening versus the acceleration many of us are seeing.

I am currently down one capacity bar, and based on the trends, expect the second one in less than a month. While I believe, maybe that capacity loss could slow, driver usage becomes a heavier factor, especially on heavy users.

I used to easily get by charging 80% at home and 80% at work. Now, if I make any additional trips after work, I am required to charge to 100% (this happened this month). Other trips during the weekends which only required 80% now require 100%. I am charging to 100% way more frequently. As for QCing, I could make trips to the north side of the dallas area and QC once on the way home, now it is required I QC on the way up and on the way home.

The situation is only going to get worse. QC 3 times just to get to the north side of the metroplex and back? 100% charging all the time (I am expecting this by the winter)? Yes, these factors are not as harsh on the battery degredation as the heat, but it will only compound the problem and make it worse. Lower capacity range = more frequent charging cycles = faster loss since we all know these batteries have only so many charging cycles in their lives. As I loose capacity, I will be quickly accelerating the cycles I put on in one day.

It is sad that in a bit over a year, I am having to change my driving habits to charge more requently than I did when I first owned the vehicle.

Have 2 questions on this issue with Capacity Loss:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Thanks All.

dsh said:

Have 2 questions on this issue with Capacity Loss:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Thanks All.

Click to expand...

i do think that the LEAF does throttle back the charge a bit due to high ambient temps but i dont think it is that much. maybe 2-3% at most. without knowing the temps where the issues start to get serious, duration factors if any, degradation rates, etc. its a tough call

dsh said:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Click to expand...

It seems conceivable, but I don't think this has been confirmed. We should know the answer come fall.

dsh said:

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Click to expand...

Not at all. In fact, there is some anecdotal evidence that 120V charging is less harmful to your battery:

Phoenix and Hot Climate LEAFs - Try L1 Charging

OTOH, L1 charging is less efficient than L2 charging, meaning you will use more electricity from the wall to charge the car.

dsh said:

Have 2 questions on this issue with Capacity Loss:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Thanks All.

Click to expand...

We don't have acces to the battery degradation data as reported by the car (edit: with the exception of the obvious missing capacity bars at 85%, 78%, 71%, etc). We will when LEAFscan is released later this year.

There is a heat indexed limit to charging that we can only guess at the particulars. Dave guessed 2-3%; I've observed almost 10% at over 136F degrees (battery temp) when measuring stored energy via the Gidmeter at a "full" charge. When my battery returned to 70F ambient temperature later that day, it returned to 99% stored energy when fully charged.

Clearly, we don't have detailed data in this area, however it's just not that hard to get. Heating the battery is easy with multiple QC, then measuring the Gid count at set temperatures of the battery at "full" charges. Let the battery cool to 70F, and measure again. It should have returned to its original Gid count.

Please don't directly confuse this "temperature related charging inhibitor protocol" with permanent loss of capacity as reported by the battery capacity gauge. You will not get that back.

RegGuheert said:

dsh said:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Click to expand...

It seems conceivable, but I don't think this has been confirmed. We should know the answer come fall.

dsh said:

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Click to expand...

Not at all. In fact, there is some anecdotal evidence that 120V charging is less harmful to your battery:

Phoenix and Hot Climate LEAFs - Try L1 Charging

OTOH, L1 charging is less efficient than L2 charging, meaning you will use more electricity from the wall to charge the car.

Click to expand...

I'm in the Dallas area and I'm doing L1 charging. I'd rather pay for a little bit more electricity if it means I'm a bit more gentle on the battery.

edatoakrun said:

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!

Click to expand...

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! :roll:

If only we could idiot-proof the forum.

azdre said:

edatoakrun said:

The improved idiot-proof LEAF!

Click to expand...

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! :roll:

If only we could idiot-proof the forum.

Click to expand...

The idiot proof LEAF would still need gas. The idiot proof forum would have no users :mrgreen:

When push comes to shove, each of us need to realize that Nissan will do exactly what works for Nissan first, and that likely will be what is cheapest "today". Expect more clinging to "range is not covered" all the way to sub 100 unit USA sales per month and new "facts" like "5 hours in 110F". That big 'ole factory in Tennessee can make as many or as few LEAFs as needed.

dsh said:

Have 2 questions on this issue with Capacity Loss:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Thanks All.

Click to expand...

In a hot climate I think using the L1 is beneficial if that is needed to park outside to get maximum battery cooling overnight.
If you are parked in a garage that stays 20F+ over ambient then you are increasing the average temp significantly.

TonyWilliams said:

dsh said:

Have 2 questions on this issue with Capacity Loss:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Thanks All.

Click to expand...

We don't have acces to the battery degradation data as reported by the car (edit: with the exception of the obvious missing capacity bars at 85%, 78%, 71%, etc). We will when LEAFscan is released later this year.

There is a heat indexed limit to charging that we can only guess at the particulars. Dave guessed 2-3%; I've observed almost 10% at over 136F degrees (battery temp) when measuring stored energy via the Gidmeter at a "full" charge. When my battery returned to 70F ambient temperature later that day, it returned to 99% stored energy when fully charged.

Clearly, we don't have detailed data in this area, however it's just not that hard to get. Heating the battery is easy with multiple QC, then measuring the Gid count at set temperatures of the battery at "full" charges. Let the battery cool to 70F, and measure again. It should have returned to its original Gid count.

Please don't directly confuse this "temperature related charging inhibitor protocol" with permanent loss of capacity as reported by the battery capacity gauge. You will not get that back.

Click to expand...

keep in mind my estimate is not "climate adjusted." factor in the "Phoenix effect" and it maybe 10%, in fact we can reason as (or create more rumor) by thinking...

now if we flip it a bit. i saw just over 19 KWH stored when my batteries this past winter were in the 30'sº range. so if we take a balance point of sorts to be 70F 35 is well, 35 º away and if 19.5/21.5= 90.6% or a "temporary temperature induced degradation" (or TTID) of 9.4%.

or we can take 105º which is still the same 35º away and then, i could see the TTID of about 10% which is in itself, acceptable and workable.

the problem is cold does not seem to have any lasting damage that i am aware of where heat does. i have always suspected that the AZ people who are reporting 20-25% loss is really only seeing 10-15% permanent loss with the rest being TTID.

so we go back to Nissan's "advisory" warning that passes in absence of a regular warranty of 20% in 5, 30 % in 10 which implies 2% a year after the initial breakin or whatever which means about 12 % in the first year or so. only then do we throw in penalties for OBA (owner battery abuse) whcih then brings us to just about what many Phoenicians are seeing.

edatoakrun said:

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

Click to expand...

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

edatoakrun said:

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...

Click to expand...

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? :lol:

azdre said:

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! :roll:

If only we could idiot-proof the forum.

Click to expand...

+1 and well said.

DaveinOlyWA said:

TonyWilliams said:

dsh said:

Have 2 questions on this issue with Capacity Loss:

I am understanding correctly we could actually see a Battery Capacity bar being added back on? I.E. have 10 bars, but in winter may see 11 due to cooler weather?

Also, if I am using the 120V trickle charge when charging at my home(Waiting for EcoTality to install the 240V charger, will this damage the batteries?

Thanks All.

Click to expand...

We don't have acces to the battery degradation data as reported by the car (edit: with the exception of the obvious missing capacity bars at 85%, 78%, 71%, etc). We will when LEAFscan is released later this year.

There is a heat indexed limit to charging that we can only guess at the particulars. Dave guessed 2-3%; I've observed almost 10% at over 136F degrees (battery temp) when measuring stored energy via the Gidmeter at a "full" charge. When my battery returned to 70F ambient temperature later that day, it returned to 99% stored energy when fully charged.

Clearly, we don't have detailed data in this area, however it's just not that hard to get. Heating the battery is easy with multiple QC, then measuring the Gid count at set temperatures of the battery at "full" charges. Let the battery cool to 70F, and measure again. It should have returned to its original Gid count.

Please don't directly confuse this "temperature related charging inhibitor protocol" with permanent loss of capacity as reported by the battery capacity gauge. You will not get that back.

Click to expand...

keep in mind my estimate is not "climate adjusted." factor in the "Phoenix effect" and it maybe 10%, in fact we can reason as (or create more rumor) by thinking...

now if we flip it a bit. i saw just over 19 KWH stored when my batteries this past winter were in the 30'sº range. so if we take a balance point of sorts to be 70F 35 is well, 35 º away and if 19.5/21.5= 90.6% or a "temporary temperature induced degradation" (or TTID) of 9.4%.

or we can take 105º which is still the same 35º away and then, i could see the TTID of about 10% which is in itself, acceptable and workable.

the problem is cold does not seem to have any lasting damage that i am aware of where heat does. i have always suspected that the AZ people who are reporting 20-25% loss is really only seeing 10-15% permanent loss with the rest being TTID.

so we go back to Nissan's "advisory" warning that passes in absence of a regular warranty of 20% in 5, 30 % in 10 which implies 2% a year after the initial breakin or whatever which means about 12 % in the first year or so. only then do we throw in penalties for OBA (owner battery abuse) whcih then brings us to just about what many Phoenicians are seeing.

Click to expand...

Not sure why Nissan does not do some bragging about their technology IF they have some sizzle in their software, etc.

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.

phxsmiley said:

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.

Click to expand...

So sorry, Smiley. I feel your pain.

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. :lol:

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.

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;

shrink said:

edatoakrun said:

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

Click to expand...

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

edatoakrun said:

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...

Click to expand...

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? :lol:

azdre said:

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! :roll:

If only we could idiot-proof the forum.

Click to expand...

+1 and well said.

Click to expand...

opossum said:

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. :lol:

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.

Click to expand...

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