Capacity Loss on 2011-2012 LEAFs

[azdre]

Some great information from GerryAZ regarding the broken gauges after losing a bar he's documented in the Collecting data:Off-the-wall power for turtle to 100% charge thread.

Incidentally, the car's instrumentation became erratic after losing the first capacity bar. SOC bars sometimes disappear quickly and other times are more like they used to be. The GOM (Nissan calls it the DTE meter) is all over the place--much worse than it was before losing the capacity bar. The first low battery warning (LBW) consistently comes sooner than it did before, but the range between LBW and the very low battery warning (VLBW) has increased significantly and the distance from VLBW to Turtle has also increased about the same amount as the increase between LBW and VLBW. The net effect is that the range is about the same as before the loss of the capacity bar, but much more of the mileage is after LBW.

Edited to add: I lost the second capacity bar at 13834 miles on 8/8/2012 (just before going on vacation), but I have not noted any additional changes to the instrumentation or loss of actual driving range.

I don't see the same behavior. I've heard of others complain about an erratic GOM, but ours moves pretty steadily as expected. Up hills and at faster speeds, it drops about 2 miles per 1 mile travelled as it did a year ago, and down hills and at constant low speeds, it goes up a little, or doesn't go down much. I also haven't seen a difference in the range between LBW and VLBW, it seems to be about 6 miles at 4.5-5 mi/kWh. In fact, I've found the GOM to be very accurate, and I find it funny to call it a guess at all in our case. Currently at a 100% charge, it claims 63 miles available, and that matches very well with what we can get if we were to take it beyond VLBW. Maybe it's because our driving is very consistant, we hyper-mile pretty well, keep it at 60 or below almost all of the time, always are in Eco, and never smash the accelerator. I'm not trying to say others don't do those things, but it might be an explanation for our seemingly accurate range gauge. I guess we'll know in a week how accurate it really is for sure if we have 30 miles hidden below VLBW.

 

[tbleakne]

Incidentally, the car's instrumentation became erratic after losing the first capacity bar. SOC bars sometimes disappear quickly and other times are more like they used to be. The GOM (Nissan calls it the DTE meter) is all over the place--much worse than it was before losing the capacity bar. The first low battery warning (LBW) consistently comes sooner than it did before, but the range between LBW and the very low battery warning (VLBW) has increased significantly and the distance from VLBW to Turtle has also increased about the same amount as the increase between LBW and VLBW. The net effect is that the range is about the same as before the loss of the capacity bar, but much more of the mileage is after LBW.

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I don't see the same behavior. I've heard of others complain about an erratic GOM, but ours moves pretty steadily as expected. Up hills and at faster speeds, it drops about 2 miles per 1 mile travelled as it did a year ago, and down hills and at constant low speeds, it goes up a little, or doesn't go down much. I also haven't seen a difference in the range between LBW and VLBW, it seems to be about 6 miles at 4.5-5 mi/kWh. In fact, I've found the GOM to be very accurate, and I find it funny to call it a guess at all in our case. Currently at a 100% charge, it claims 63 miles available, and that matches very well with what we can get if we were to take it beyond VLBW. Maybe it's because our driving is very consistant, we hyper-mile pretty well, keep it at 60 or below almost all of the time, always are in Eco, and never smash the accelerator. I'm not trying to say others don't do those things, but it might be an explanation for our seemingly accurate range gauge. I guess we'll know in a week how accurate it really is for sure if we have 30 miles hidden below VLBW.

My understanding is that a different chemical reaction causes battery degradation at the very bottom of SOC. The Li-ions are at the opposite electrode. Even if more miles can be extracted below LBW, I doubt if very many of us want to go there on a regular basis.

Has anyone with a Gid meter checked the voltage at LBW or VLBW for a 2 or 3-bar loser car ? Perhaps in this long thread that has been done. If the voltages at these points have not changed, as I would expect, then I would view the warnings as retaining their original meaning and not off from "meter error."

 

[shrink]

Ran into another local LEAF owner at Trader Joe's this evening. They had purchased the car from the same dealer and salesman as my 2011 and they had the car about a year ago. Asked if there was any battery degradation and they said that "it seemed" the range on the GOM was lower, but they weren't sure.

Took a look at the dash and 2 capacity bars were missing. Exchanged some contact info and gave them some links to this site and the wiki.

I have the car VIN, but I'm not going to report without their permission. Very nice folks and I imagine they are typical owners.

I'm almost certain most similarly aged LEAF's in Phoenix are missing capacity bars. Most owners may not be aware...

 

[RegGuheert]

I'm almost certain most sinilarly aged LEAF's in Phoenix are missing capacity bars. Most owners may not be aware...

I agree that is quite possible, particularly for owners who normally charge to 80%.

 

[Volusiano]

49.5 miles driven so far today. 5.1 miles/kWhr average. So I've used 9.7 kWhr. Plugged into L3 Blink. It said SOC was 37%. So 63% used. 9.7/0.37 = 15.4 kWhr. If you assume 21 kWhr is a new pack, we're at 73.4%. It's a toasty good time on the fast charger right now! The fun continues...

I did calculation with my car (2 bar loss) using the same approach you did:

47.2 miles driven at 4.95 m/kwh avg. So I'ved used 9.54 kwh. Plugged into L3 Blink, it said SOC was 33% remained, so 67% used. 9.54/0.33 = 14.24 kwh reduced total capacity on my battery. If you assume 21 kwh is a new pack, I'm at 68%.

What doesn't add up is that I've only shown 2 bar loss so far. So I should be at around 72.5% or more. But I'm at 68% instead. So either there's some error in the calculation, or I'm VERY CLOSE to seeing my 3rd bar loss any day now.

 

[reedwick]

First Post to the forum, so please excuse any mistakes in etiquette.

I'm in San Diego. Got my Leaf in April 2011 (17 months old), VIN: 00770. Just lost my first capacity bar this morning after a little less than 21k miles.

Garage kept 99% of the time (both home and office), L2 Charge to 100% starting at midnight. My temperature gauge has never gone to 7 bars. It is 5 bars most of the time, sometimes 6. Due to the mostly highway driving, I get 3.6-3.7 miles/kWhr average.

My daily commute is 57 miles mostly interstate highway. Driving 60-65mph in EV mode, I had been getting home w/ ~15 miles remaining on the range indicator. That has slid to mid-single digits in the last few weeks and this morning the car had the missing capacity bar. I haven't completed the full commute post the loss of the bar, so hopefully I'm still in the mid-single digits range remaining.

I called the Nissan hotline to report the capacity loss (case 3: 9376964), and I'm going to take it in to the dealer for an EV Battery Usage Report as soon as I have the opportunity.

If someone can add my vehicle info to the list, I'd appreciate it, I wasn't sure how to do it.

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

 

[djchrispaul]

After swapping my purchased 2011 leaf because of 9of 12 bars on 80% for a leased 2012 leaf in June, I have 935 miles on it and today was the first time I got 9of 12 bars on 80% charge. It has been an xtremely hot summer as it always is here in Palm Springs but this is ridiculous.
I have been getting 55 approx miles on 80% charge and barely 65 on 100%. Also if I leave it parked for a few hours I also lose a bar.
So I have had 2 leafs and can confirm that I am over it now!
50-60 mile range on 3.2 kwh mile. Is really not acceptable no matter how carefully I drive it, bottom line, hot weather, get a different car. Now I'm stuck with it for 3 years!

 

[RegGuheert]

I'm in San Diego. Got my Leaf in April 2011 (17 months old), VIN: 00770. Just lost my first capacity bar this morning after a little less than 21k miles.

Welcome to the forum. Sorry to hear about your lost bar.

Added reedwick to the wiki as the 82nd report of at least one lost bar.

BTW, reedwick, can you please swap the month and day for delivery date in the User Control Panel and let us know the manufacturing month from the pillar inside the driver's door? TIA!

 

[shrink]

I have 935 miles on it and today was the first time I got 9of 12 bars on 80% charge. It has been an xtremely hot summer as it always is here in Palm Springs but this is ridiculous.

The same thing happened to my new 2012 LEAF about a month ago during the record heat in August. I'm back to a consistent 10/12 on an 80% charge. I wouldn't worry too much, but don't be surprised if in a year the bars start dropping again. It's why I only did a 24-month lease.

 

[Stoaty]

Added reedwick to the wiki as the 82nd report of at least one lost bar.

There are actually 83 one bar losers. One of the 3 bar losers (Kristy Bryant) did not have info on bars one or two. The report was from Facebook, where she was kicking up a storm on the Nissan Leaf site because she was upset. I didn't enter her in the one bar or two bar loser categories, because I didn't know where to put her there. The correct number (83) is at this link in the summary:

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

 

[JimSouCal]

There is a fan inside

For some reason I thought there was an internal fan to even out heat distribution. Guess I dreamt that up in my head.

No, you didn't dream it up. Nissan said there was a fan once-upon-a-time, but it never materialized in the production car.

Theoretically the "cooling" system is passive radiation from the pack to the outside air, obviously not effective in this case.

It's difficult to radiate heat to the air since air does not absorb infrared light effectively. Any radiation from the LEAF battery would be to other surfaces that surround it such as the floorboards or the plastic sheet below it, and, yes, that is pretty limited.

Most of the cooling of the LEAF battery when driving is through conduction to the unibody and conduction from both the battery and the unibody to the air. When the car is moving heat gets carried away by a form of convection due to the car moving to cooler air all the time. However, when the car is at rest, the warm air around the battery is somewhat trapped so the heat takes a long time to dissipate.

Since the LEAF battery is a net dissipater of heat, the lower temperature limit is the ambient air temperature. In reality, its average temperature will be above the ambient level. This is good when it is cold outside and bad when it is hot.

This is consistent with my elementary test of running a sprinkler underneath the car just to see what happened to battery temps from a 7 bar reading on an 80 degree day here in westside of los angeles. Nada. No lowering after two hours of cool water streaming on the underside.

I am left to wonder just how much cabin temps and the surface temps affects the battery given the assumption that the body is effectively a heat sink for the battery? Finding shade for parking would seem to make sense for a bunch of reasons?

Note: no bar loss here YET, but I feel for those who are grappling with the issue...

 

[mwalsh]

I am left to wonder just how much cabin temps and the surface temps affects the battery given the assumption that the body is effectively a heat sink for the battery?

I was wondering the same thing just recently after a non-charging, fairly cool night. In the morning, before the sun came up, I observed battery temps at 4 bars, but had 6 by the time I went back out to the car in the late afternoon/early evening. The car never moved the entire day, so the temp increase was entirely down to conduction and/or radiation.

 

[gaswalla]

First Post to the forum, so please excuse any mistakes in etiquette.

I'm in San Diego. Got my Leaf in April 2011 (17 months old), VIN: 00770. Just lost my first capacity bar this morning after a little less than 21k miles.

Garage kept 99% of the time (both home and office), L2 Charge to 100% starting at midnight. My temperature gauge has never gone to 7 bars. It is 5 bars most of the time, sometimes 6. Due to the mostly highway driving, I get 3.6-3.7 miles/kWhr average.

This is VERY concerning - I know folks are going to point to the 100% charging - but this guy is from Encinitas: which is on the coast.. and it is always in the 65-75 degree range except for a few weeks in Aug/Sept when it goes up to 80.

I think we are all underappreciating the role of keeping the car in the garage - that probably played a huge role in this car's degradation... in my humble opinion

 

[LEAFfan]

After swapping my purchased 2011 leaf because of 9of 12 bars on 80% for a leased 2012 leaf in June, I have 935 miles on it and today was the first time I got 9of 12 bars on 80% charge. It has been an xtremely hot summer as it always is here in Palm Springs but this is ridiculous.
I have been getting 55 approx miles on 80% charge and barely 65 on 100%. Also if I leave it parked for a few hours I also lose a bar.
So I have had 2 leafs and can confirm that I am over it now!
50-60 mile range on 3.2 kwh mile. Is really not acceptable no matter how carefully I drive it, bottom line, hot weather, get a different car. Now I'm stuck with it for 3 years!

If you drive it hard and only get 3.2/kW h, then that's why your range is so low, not because of the battery. At 80% charge you will get 54 miles (17 X 3.2) until Turtle and at 100% charge 67 miles (21 X 21) until Turtle. If you were able to get at least 4.0m/kW h, you would see your miles increase significantly. Using ECO and some coasting in 'N', you should easily get at least 4.0.

 

[reedwick]

First Post to the forum, so please excuse any mistakes in etiquette.

I'm in San Diego. Got my Leaf in April 2011 (17 months old), VIN: 00770. Just lost my first capacity bar this morning after a little less than 21k miles.

Garage kept 99% of the time (both home and office), L2 Charge to 100% starting at midnight. My temperature gauge has never gone to 7 bars. It is 5 bars most of the time, sometimes 6. Due to the mostly highway driving, I get 3.6-3.7 miles/kWhr average.

This is VERY concerning - I know folks are going to point to the 100% charging - but this guy is from Encinitas: which is on the coast.. and it is always in the 65-75 degree range except for a few weeks in Aug/Sept when it goes up to 80.

I think we are all underappreciating the role of keeping the car in the garage - that probably played a huge role in this car's degradation... in my humble opinion

I have been being careful to always park in the garage - Am I missing something? Is there reason to think that the garage is worse for the battery than parking outside? The garage I park in during the day is underground (not hotter than 75). Confused about how this might be the cause?

The only thing I can think of that I could possibly change to extend the life of the battery is to charge to 80%, but given the length of my commute, that's just not possible.

 

[mwalsh]

I have been being careful to always park in the garage - Am I missing something? Is there reason to think that the garage is worse for the battery than parking outside? The garage I park in during the day is underground (not hotter than 75). Confused about how this might be the cause?

The only thing I can think of that I could possibly change to extend the life of the battery is to charge to 80%, but given the length of my commute, that's just not possible.

I think he's thinking that parking outside at night, giving the car a chance to cool in the night air, is a better choice. I must say that I feel that way myself - our garage gets gawd awful hot in summer time, and stays that way the whole night. Yet, with clear skies, outdoor temps can easily dip into the mid to high 60s, even after a 90 plus degree day.

 

[Randy]

Reedwick,
I'm in San Diego too, although I haven't lost a capacity bar yet. I took delivery in early January 2011. I have 13,000 miles currently and always drive in ECO mode.

How many miles a day do you put on the car or how many bars are left on the gauge when you pull back in the garage at the end of the day? It's rare for me to be at less than 4-5 bars when I recharge (to 80% most of the time)....

Thanks, Randy

 

[reedwick]

My drive is 57 miles round trip - straight shot from Encinitas to downtown SD and back. Until about a month ago, I'd consistently have 2 bars (and about ~15m indicated range) left when I pulled into my driveway. Now I have 0-1 bars and 0-5 miles indicated range. I drive 65 on the highway (hard to drive much slower on I5), and get an average 3.6-3.7 m/kWh.

I may start leaving the car in the driveway until after dark so the garage cools off. I get home ~4:30 or 5:00 so that afternoon sun could make the garage a little on the warm side I suppose.

For those that park outside, are you running your L2 charger cord under the garage door out into the driveway to charge? Or just charging at other times?

 

[mwalsh]

For those that park outside, are you running your L2 charger cord under the garage door out into the driveway to charge? Or just charging at other times?

Under the garage door for me. It's a pretty hefty cord, and would probably survive a fair bit of abuse anyway, but I make a point of stopping the door just as the rubber seal on the bottom of it is kissing the cord, so it doesn't get pinched in any way.

 

[dsh]

I also ran into a LEAF owner at ABC Nissan this weekend...He also had 1 capacity bar missing...I informed him of Toll Free LEAF # and Forum to report...Looks like a lot of LEAF owners have capacity bars missing, but do not report them.

Ran into another local LEAF owner at Trader Joe's this evening. They had purchased the car from the same dealer and salesman as my 2011 and they had the car about a year ago. Asked if there was any battery degradation and they said that "it seemed" the range on the GOM was lower, but they weren't sure.

Took a look at the dash and 2 capacity bars were missing. Exchanged some contact info and gave them some links to this site and the wiki.

I have the car VIN, but I'm not going to report without their permission. Very nice folks and I imagine they are typical owners.

I'm almost certain most similarly aged LEAF's in Phoenix are missing capacity bars. Most owners may not be aware...