Capacity Loss on 2011-2012 LEAFs

[turbo2ltr]

I had a dream last night... that I looked at my phone, and it had a red box around the battery icon indicating I had lost capacity. When I unplugged it from the charger, it battery icon was only partially full.

I wonder if I can sue Nissan for emotional distress. lol (I'm kidding, but I really did have that dream.)

 

[SanDust]

Some are advocating leasing over buying in hot climates, based on this discussion, but I for one would not even recommend leasing a Leaf at this point!

Leasing is a fine idea so long as your commute isn't pushing the range. We have people who post asking if the Leaf will work for their 80 mile commute. Lots of Leafers say "sure you can do this easy" but I've always said "no way, not enough margin for error". I've got a 35 mile commute. Even if I were in Phoenix this would be a workable commute for the duration of the lease. Yes leasing the Leaf is a fine idea so long as your commute is 40 miles or less (you'd be able to push that no doubt).

The other point to keep in mind is that the capacity loss is not likely to be linear. Usually batteries lose capacity over the first few hundred cycles and then degrade much more slowly. If you've seen a 15% degradation the first year I wouldn't expect you to see it again next year. Nissan has tested these batteries. Its engineers may have slightly miscalculated but I doubt they're off by a huge amount. I'm still thinking 70% of capacity at five years at a minimum.

There are also a couple of other issues at work. With respect to your Nissan rage, I get that. The marketing for the Leaf was downright misleading. Not only did we have Mark Perry shouting about the 100 mile range, which was a load of crap, we had the issue of not disclosing that recommended charging was only to 80%. And there was a complete lack of candor when describing that batteries would degrade faster in hot climates and how that would be affected by the lack of a TMS. If the expectations had been set better I think you'd feel differently. The second issue is the capacity bars. I'm convinced that many people lamenting the loss of capacity would be claiming no loss of capacity if the lost bar wasn't staring them in the face. At some level people believe what they want to believe, and lots of folks here wanted to believe that the Leaf battery wouldn't lose capacity. (A good example of this is that someone directed me to a Tesla forum where Roadster owners were swearing up and down that their car's battery packs had suffered no capacity loss whatsoever after years of service, which is not bad for cells guaranteed to lose 20% of capacity over 300 cycles even in moderate temperatures).

 

[DaveinOlyWA]

Again, yes. I said this over a year ago quite a few times that leasing this car was, in my opinion, a far better way to finance because of the new technology and unknowns.

Train, What kind of car do you drive ?

turbo charged 10 L diesel

 

[ecoobsessive]

Add me to the list. I predict most of the other 1 year old Texas cars will fall soon. I got in the car this morning after the regular 80% charge (which has given me 9 fuel bars lately) and at first thought I had 10 fuel bars since it was 2 below the capacity bars. It took a bit of staring and counting bars until I admitted to myself that yes, I'm at 11 capacity bars now. I'm sure I would not have noticed this for awhile if it had not been for MNL, and so I had been checking capacity bars every day. Had the 1 year battery check in May, had 5 stars all the way across. Almost always charge to 80%. Charged to 100% less than 50 days during the past 13 months. Never kept the battery at 100% for long. Battery temp. bars is nearly always at 6 bars. I have not yet hit 7 battery temp. so far this summer. Last summer had 7 temp. bars several times, but only got to 7 at the end of my commute home. Park in sun (no available shade) at work. Garage at night. Average garage temp. in June: 85F, August: low 90s. If I had expected to lose 15% in 1 year I would have gotten the lease. Note to Nissan: I want you to buy back my car for a fair price 15-20 months from now so I can buy or lease a 2013/14 LEAF with a "hot weather package" and TMS.

only 13K miles. 13 months

 

[Herm]

Battery temp. bars is nearly always at 6 bars. I have not yet hit 7 battery temp. so far this summer. Last summer had 7 temp. bars several times, but only got to 7 at the end of my commute home. only 13K miles. 13 months

The 6th bar ranges from 74° F to 98° F, 74° is nearly ideal and 98° is pretty warm for lithium-ion batteries. That 6th bar is too coarse as to be useful.

 

[SanDust]

The 6th bar ranges from 74° F to 98° F, 74° is nearly ideal and 98° is pretty warm for lithium-ion batteries. That 6th bar is too coarse as to be useful.

Where does the 74F number come from? I'm living at six bars, including in the morning when the ambient air temp is between 64F and 68F. Granted that's after charging but it hasn't hit 70F more than a few times even in the middle of the day.

 

[Stoaty]

Where does the 74F number come from? I'm living at six bars, including in the morning when the ambient air temp is between 64F and 68F.

Right here in the Wiki:

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

with Service Manual reference.

 

[leafkabob]

Adding ecoobsessive and correcting Opossum's "third-party" report at the bottom.

1. Azdre & Opossum - April 26, 2012. 16.6K miles/13 months ownership. Phoenix (2nd bar loss reported 6/14/2012 @~19K miles)
2. bturner - May 12, 2012. 13.6K/12 months. Phoenix
3. turbo2ltr - May 18, 2012. 13K/15 months. Phoenix (2nd bar loss reported 6/29/2012)
4. TickTock - May 20, 2012. 14K/12 months Phoenix
5. Volusiano - May 20, 2012. 16.5K/12 months. Phoenix
6. Mark13 - May 22, 2012. 15.7K/12 months. Phoenix (2nd bar loss reported 7/1/2012)
7. Leafkabob - May 26, 2012. 9.5K/12 months. Phoenix
8. Cyellen - June 7, 2012. 10.2K/ 14 months. Phoenix
9. RickS - June 10, 2012. 11.3K/13 months. Phoenix
10. Pipcecil - June 17, 2012. 20.2K/12 months. Dallas, Texas
11. Phxsmiley - June 17, 2012. 13.7K/10 months. Phoenix
12. AZknauer - June 17, 2012. 9.2K/13.5 months. Phoenix
13. Myleaf - June 19, 2012. 13.3K/14 months. Phoenix
14. johndoe74 - June 5, 2012. 13.5K/ 9 months. Phoenix
15. Matt Ferris - June 20, 2012. 15K/ 12 months. Dallas, Texas
16. Shrink - June 21, 2012. 10.2K/ 10.5 months. Phoenix (sold that Leaf, replaced w/leased '12 Leaf)
17. ravi100 - June 24, 2012. 13.1K/ 13.5 months. Southlake, Texas (no longer has Leaf)
18. ev4me - approx. June 1, 2012. 7K/ 15 mos. Phoenix (Dropped 2 bars)
19. jspearman - June 28, 2012, ?/10.5 months. Phoenix
20. Leafwing - July 05, 2012, 13.5K/15 months, Plano, TX.
21. GerryAZ - July 05, 2012, ?/?, Phoenix
22. ecoobsessive - July 6, 2012, 13K/13 months, San Antonio, TX

Not reported by owner, but by others:
1. Opossum reported knowing of another car in Phoenix that has lost 2 bars.
2. Leafkabob reported a street encounter with a Leaf owner who stated he lost a bar after about a year.
3. Skywagon approx. May, 2012. Phoenix (supposedly no longer has Leaf)

 

[SanDust]

Thanks. So weird that the ambient is never 74F but there is always six bars.

 

[jspearman]

I'm convinced that many people lamenting the loss of capacity would be claiming no loss of capacity if the lost bar wasn't staring them in the face.

My fully-charged range dropped precipitously and I definitely noticed. When it dipped down into the mid-80 mile range, that's when I really got concerned and started searching the web to find out what was happening. A week later I had lost the first bar.

 

[RegGuheert]

The 6th bar ranges from 74° F to 98° F, 74° is nearly ideal and 98° is pretty warm for lithium-ion batteries. That 6th bar is too coarse as to be useful.

Where does the 74F number come from? I'm living at six bars, including in the morning when the ambient air temp is between 64F and 68F.

Right here in the Wiki:

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

with Service Manual reference.

That reference is to the "old" Service Manual. That chart has been replaced by a graph in the April 2011 Revision of the LEAF Service Manual and the temperature ranges given are different:

RELATIONSHIPS OF THE NUMBER OF LIGHTING SEGMENTS OF LI-ION BATTERY TEMPERATURE GAUGE AND LI-ION BATTERY TEMPERATURE
0 Bars: Up to -5C (23F)
1 Bar: -15C (5F) to -2C (28F)
2 Bars: -12C (10F) to 2C (36F)
3 Bars: -8C (18F) to 4C (39F)
4 Bars: -5C (23F) to 15C (59F)
5 Bars: -3C (27F) to 27C (81F)
6 Bars: 10C (50F) to 38C (100F)
7 Bars: 23C (73F) to 47C (117F)
8 Bars: 36C (97F) to 49C (120F)
9 Bars: 47C (117F) to 52C (126F)
10 Bars: 49C (120F) to 56C (133F)
11 Bars: 52C (126F) to 59C (138F)
12 Bars: 56C (133F) and above
Note:
- Li-ion battery temperature gauge shows Li-ion battery temperature by correcting it according to the battery capacity. Consequently, the number of lighting segments of Li-ion battery temperature gauge can be different regardless of the same Li-ion battery temperature.
- This graph shows corrected temperatures. These to not agree with the CONSULT temperature shown in data monitor item "BAT TEMP".

(Please note that I have interpreted the graph so that the range values can be read as numbers.)

I must say that I am not quite sure what "correcting it according to battery capacity" means. That almost implies to me that they are attempting to calculate the temperature inside the cells by using a crude thermal model and adjusting losses in the battery based on degradation information. Any other ideas?

 

[planet4ever]

That reference is to the "old" Service Manual. That chart has been replaced by a graph in the April 2011 Revision of the LEAF Service Manual and the temperature ranges given are different

You beat me to it; I was writing much the same thing as you posted. But I wouldn't say they are "different". The wiki says it is for a new battery, and I think you have to interpret the table there as transition points when the battery is cooling, not heating. So 6 bars is 74.3F down to 50.5F. If you look at your interpolated values the low end numbers match quite well.

I must say that I am not quite sure what "correcting it according to battery capacity" means. That almost implies to me that they are attempting to calculate the temperature inside the cells by using a crude thermal model and adjusting losses in the battery based on degradation information. Any other ideas?

I think Nissan is trying to give us an indication of how hard we are being on our battery. The temperatures for a given number of bars go up as the battery ages because it is getting "more used" to the higher temperatures. Put less anthropomorphically, for a given temperature an already degraded battery no longer degrades as fast as it did when it was new. Sound familiar?

Ray

 

[jhm614]

Please put me in the "lost two bars" camp. The first bar disappeared around May 15th and the second bar went bye-bye this week.

 

[DaveinOlyWA]

Please put me in the "lost two bars" camp. The first bar disappeared around May 15th and the second bar went bye-bye this week.

@25K miles, you must drive a lot. are you near turtle on your normal commutes?

 

[Herm]

@25K miles, you must drive a lot. are you near turtle on your normal commutes?

Assuming 335 driving days per year that works out to 60 miles a day, so not necessarily down to turtle, when the battery is new.

 

[TomT]

I started to see 9 bars on 80% from time to time about four weeks ago after a year and half and 20,000 miles... It seems to be happening more often these days. My Gid meter was stolen so I can't give any hard numbers at the moment but I'm poised waiting for the first tick to go away... This would be most interesting as my car has been subjected to what would be considered a fairly mild climate only (garaged at home and at night in the milder Granada Hills foothills area of the SFV, and parked outdoors in the cooler Santa Monica area during the work day)... It has only had one QC in its lifetime and 95% of the time is charged to 80 percent... I typically arrive home with about 2 bars so I am not pushing the battery particularly hard (my round-trip commute is about 47 miles but there are substantial elevation changes and it is mostly freeway which I typically drive at around 62-63 mph on the non-congested sections)... I did try a few 100% charges in case equalization was an issue but it appears to have made no difference.

I'm on a four year/15K lease so I am not particularly concerned but it is interesting nonetheless.

 

[Volusiano]

Adding jhm614 2 capacity bar loss.

1. Azdre & Opossum - April 26, 2012. 16.6K miles/13 months ownership. Phoenix (2nd bar loss reported 6/14/2012 @~19K miles)
2. bturner - May 12, 2012. 13.6K/12 months. Phoenix
3. turbo2ltr - May 18, 2012. 13K/15 months. Phoenix (2nd bar loss reported 6/29/2012)
4. TickTock - May 20, 2012. 14K/12 months Phoenix
5. Volusiano - May 20, 2012. 16.5K/12 months. Phoenix
6. Mark13 - May 22, 2012. 15.7K/12 months. Phoenix (2nd bar loss reported 7/1/2012)
7. Leafkabob - May 26, 2012. 9.5K/12 months. Phoenix
8. Cyellen - June 7, 2012. 10.2K/ 14 months. Phoenix
9. RickS - June 10, 2012. 11.3K/13 months. Phoenix
10. Pipcecil - June 17, 2012. 20.2K/12 months. Dallas, Texas
11. Phxsmiley - June 17, 2012. 13.7K/10 months. Phoenix
12. AZknauer - June 17, 2012. 9.2K/13.5 months. Phoenix
13. Myleaf - June 19, 2012. 13.3K/14 months. Phoenix
14. johndoe74 - June 5, 2012. 13.5K/ 9 months. Phoenix
15. Matt Ferris - June 20, 2012. 15K/ 12 months. Dallas, Texas
16. Shrink - June 21, 2012. 10.2K/ 10.5 months. Phoenix (sold that Leaf, replaced w/leased '12 Leaf)
17. ravi100 - June 24, 2012. 13.1K/ 13.5 months. Southlake, Texas (no longer has Leaf)
18. ev4me - approx. June 1, 2012. 7K/ 15 mos. Phoenix (Dropped 2 bars)
19. jspearman - June 28, 2012, ?/10.5 months. Phoenix
20. Leafwing - July 05, 2012, 13.5K/15 months, Plano, TX.
21. GerryAZ - July 05, 2012, ?/?, Phoenix
22. ecoobsessive - July 6, 2012, 13K/13 months, San Antonio, TX
23. jhm614 - May 15, 2012, 25K/14.5 months, Arlington, TX (2nd bar loss reported on 7/7/2012)

Not reported by owner, but by others:
1. Opossum reported knowing of another car in Phoenix that has lost 2 bars.
2. Leafkabob reported a street encounter with a Leaf owner who stated he lost a bar after about a year.
3. Skywagon approx. May, 2012. Phoenix (supposedly no longer has Leaf)

 

[palmermd]

1. Azdre & Opossum -               April 26, 2012.           16.6K miles/13 months ownership.         Phoenix             (2nd bar loss reported 6/14/2012 @~19K miles)
2. bturner -                       May 12, 2012.             13.6K/12 months.                         Phoenix
3. turbo2ltr -                     May 18, 2012.             13K/15 months.                           Phoenix             (2nd bar loss reported 6/29/2012)
4. TickTock -                      May 20, 2012.             14K/12 months                            Phoenix
5. Volusiano -                     May 20, 2012.             16.5K/12 months.                         Phoenix
6. Mark13 -                        May 22, 2012.             15.7K/12 months.                         Phoenix             (2nd bar loss reported 7/1/2012)
7. Leafkabob -                     May 26, 2012.             9.5K/12 months.                          Phoenix
8. Cyellen -                       June 7, 2012.             10.2K/ 14 months.                        Phoenix
9. RickS -                         June 10, 2012.            11.3K/13 months.                         Phoenix
10. Pipcecil -                     June 17, 2012.            20.2K/12 months.                         Dallas, Texas
11. Phxsmiley -                    June 17, 2012.            13.7K/10 months.                         Phoenix
12. AZknauer -                     June 17, 2012.            9.2K/13.5 months.                        Phoenix
13. Myleaf -                       June 19, 2012.            13.3K/14 months.                         Phoenix
14. johndoe74 -                    June 5, 2012.             13.5K/ 9 months.                         Phoenix
15. Matt Ferris -                  June 20, 2012.            15K/ 12 months.                          Dallas, Texas
16. Shrink -                       June 21, 2012.            10.2K/ 10.5 months.                      Phoenix              (sold that Leaf, replaced w/leased '12 Leaf)
17. ravi100 -                      June 24, 2012.            13.1K/ 13.5 months.                      Southlake, Texas     (no longer has Leaf)
18. ev4me -                        approx. June 1, 2012.     7K/ 15 mos.                              Phoenix              (Dropped 2 bars)
19. jspearman -                    June 28, 2012,            ?/10.5 months.                           Phoenix
20. Leafwing -                     July 05, 2012,            13.5K/15 months,                         Plano, TX.
21. GerryAZ -                      July 05, 2012,            ?/?,                                     Phoenix
22. ecoobsessive -                 July 6, 2012,             13K/13 months,                           San Antonio, TX
23. jhm614 -                       May 15, 2012,             25K/14.5 months,                         Arlington, TX        (2nd bar loss reported on 7/7/2012)

 

[HXGuy]

Is anyone close to dropping a 3rd bar based on GID readings?

It's odd how the 2nd bar is dropping within 2-3 months of the 1st bar, will the 3rd bar follow 2-3 months later or even faster since the 1st bar took 1 year and the 2nd took just a few months.

 

[RegGuheert]

Is anyone close to dropping a 3rd bar based on GID readings?

Yes, the car owned by the OP of this thread was reading 71.8% at the end of June and they expect to lose a third bar soon:

“Azdre” (the originator of this massive thread) and I own the same Phoenix Leaf, VIN #0500. We lost our second bar several weeks ago and appear to be on the cusp of losing the third.

It's odd how the 2nd bar is dropping within 2-3 months of the 1st bar, will the 3rd bar follow 2-3 months later or even faster since the 1st bar took 1 year and the 2nd took just a few months.

Please note that the first capacity bar is worth 15% of capacity while all other bars are worth 6.25%. Some posters have reported the loss of their second bar in just 6 weeks.

So the question on everyone's mind is whether future losses of bars will happen more quickly or more slowly than the second bar. Many believe Nissan's claim that capacity losses slow with time. I am not convinced. Here is why:

There seem to be two primary factors which cause the loss of battery capacity in the LEAF: so-called calendar losses which are accelerated by high temperatures and/or storage at high states-of-charge and cycling losses which are the result of chemical reactions which are not fully reversible. Which loss mechanism dominates is a function of the temperature of the battery and how much cycling is done over time.

I think we all agree that LEAF capacity losses in Phoenix LEAFs are dominated by calendar losses.

The question in my mind is whether calendar losses follow the "slowing" that Nissan predicts. Frankly, data I have seen referenced here for other Li-ion chemistries shows calendar capacity losses *accelerating* over time. I believe Nissan's predictions will hold true for LEAFs in Seattle where cycling losses are dominant, but I seriously doubt this will be the case in PHoenix.

It seems we will have the answer soon...