Frequent use of CHAdeMO DCQC Killing 2015 Leaf Battery?!

06/29/15 * 4,264mi * 132 L1/L2s & 2 QC * 4.4 mi/kWh (for the past month):
97.2% SOC * 292 GIDs * 22.6 kWh * 62.99 AHr * 100% SOH * 97.09% Hx

07/31/2015 * 4,695 mi * 138 L1/L2s & 5 QC * 4.4 mi/kWh (for the past month):
96.6% SOC * 286 GIDs * 22.2 kWh * 61.26 AHr * 98% SOH * 94.61% Hx

10/01/2015 * 6,281 mi * 187 L1/L2s & 7 QC * 4.4 mi/kWh (for the past month):
97.3% SOC * 280 GIDs * 21.7 kWh * 57.73 AHr * 95% SOH * 91.41% Hx[/b]


During the past month, I decided to use the CHAdeMO Quick Charger at my local Nissan dealer on a regular basis, as sort of an experiment, and my battery has--perhaps coincidently--really gone to hell during this time:

10/31/2015 * 7,281 mi * 211 L1/L2s & 16 QC * 4.5 mi/kWh (for the past month):
96.2% SOC * 268 GIDs * 20.8 kWh * 57.69 AHr * 92% SOH * 88.37% Hx
(Note that these are the worst/lowest values I have recorded since buying the car about 10 months ago.)

If true, this would appear to drive a stake through the heart of the Lizard and its lack of a TMS...

Your stats show "7 QC" (DC quick charges) in the last several months. That's really not much at all. I'd expect other factors to be much more significant in your battery's apparent degradation. Ambient temperatures could be significant, but hopefully that's not the issue. Or maybe you have a weak battery cell. At this point, it's probably not worth really worrying about. Your numbers might even go back up some. And all Li-ion batteries (that I know of) tend to degrade more when they're newer. If the numbers continue declining at that rate during the winter, then perhaps there's a significant issue worth attempting to remedy.

abasile said:

Your stats show "7 QC" (DC quick charges) in the last several months. That's really not much at all. I'd expect other factors to be much more significant in your battery's apparent degradation. Ambient temperatures could be significant, but hopefully that's not the issue. Or maybe you have a weak battery cell. At this point, it's probably not worth really worrying about. Your numbers might even go back up some. And all Li-ion batteries (that I know of) tend to degrade more when they're newer. If the numbers continue declining at that rate during the winter, then perhaps there's a significant issue worth attempting to remedy.

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I would agree, I turned 39,000 miles today and had numerous QC's over the last three years. Its not unusual for me to QC 5 times in a day while traveling.

MartinChico said:

06/29/15 * 4,264mi * 132 L1/L2s & 2 QC * 4.4 mi/kWh (for the past month):
97.2% SOC * 292 GIDs * 22.6 kWh * 62.99 AHr * 100% SOH * 97.09% Hx

07/31/2015 * 4,695 mi * 138 L1/L2s & 5 QC * 4.4 mi/kWh (for the past month):
96.6% SOC * 286 GIDs * 22.2 kWh * 61.26 AHr * 98% SOH * 94.61% Hx

10/01/2015 * 6,281 mi * 187 L1/L2s & 7 QC * 4.4 mi/kWh (for the past month):
97.3% SOC * 280 GIDs * 21.7 kWh * 57.73 AHr * 95% SOH * 91.41% Hx[/b]


During the past month, I decided to use the CHAdeMO Quick Charger at my local Nissan dealer on a regular basis, as sort of an experiment, and my battery has--perhaps coincidently--really gone to hell during this time:

10/31/2015 * 7,281 mi * 211 L1/L2s & 16 QC * 4.5 mi/kWh (for the past month):
96.2% SOC * 268 GIDs * 20.8 kWh * 57.69 AHr * 92% SOH * 88.37% Hx
(Note that these are the worst/lowest values I have recorded since buying the car about 10 months ago.)

Click to expand...

Was the summer hotter this year? How many 100 degree days were there?

After about 6 months, at the moment I have:
SOC=71.6% AHr=64.38 SOH=100% odo=13,108 mi 61 QCs & 488 L1/L2s

I wonder which one is more representative, mine or yours?

Should I take another reading at SOC=100%?

Is the SOH steadily going down, or just the worse cases? What about the best cases?
I imagine some variability is OK as long as the trend is not downwards.

When was the last time the pack was properly cycled? LBW then 100% overnight charge? if the cells are not ballanced then your readings are meaningless as it will through out the accuracy.

asemeco said:

Is the SOH steadily going down, or just the worse cases? What about the best cases?
I imagine some variability is OK as long as the trend is not downwards.

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Unfortunately, the trend is clearly downwards. SOH and Hx jumped up and down a bit for the first 6-7 months--just noise, but have been declining quite steadily for past 4-5 months.

I wouldn't jump to conclusions on DCQC. You might just need to rebalance the cells in the battery. Discharging it until Very Low Battery warning and then L2 charging to 100% should see improvement to your GIDs.

I was quick charging all summer including a road trip from Seattle,WA to Medocino, CA along the California coast. I'm driving a 2015 Leaf SL. Haven't seen any battery degradation and my Leaf will be a year old in a week.

XeonPony said:

When was the last time the pack was properly cycled? LBW then 100% overnight charge? if the cells are not ballanced then your readings are meaningless as it will through out the accuracy.

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That is half right. I suspect that your pack isn't being equalized, because QC charges taper off to L-2, and most people don't wait for 100% and then EQ to happen. However, there is no need or benefit in running it down to Low Battery Warning, because equalization happens at the "top" of the charge state, not the bottom, and because lithium batteries don't have "memory effect" like some other chemistries..

well the low end is what helps the bms to learn to my understanding of things, since he will want accurate bms data for range.

Wasn't there a study performed by the Idaho National Lab that showed that degradation due to quick charging appears to have only minimal impacts? If I recall, they did an extensive test over an extended period driving Leafs that were QC and L2 charged side by side. I think the study showed that the QC least only suffered 5% more degradation. I believe that correlates to a slightly average battery temperature in the QC Leafs.

Nov 3 '14: KM - 11 962, Soh - 100%, Charges - 11 QC 256 L1/L2, Gidds - 289, kWh - 22.4, Soc - 96.4%, Hx - 101.94%, Ahr - 64.38
Jan 17 '15: KM - 19 338, Soh - 100%, Charges - 38 QC 453 L1/L2, Gidds - 292, kWh - 22.6, Soc - 97.2%, Hx - 108.32%, Ahr - 64.38
Mar 31 '15: KM - 26 786, Soh - 100%, Charges - 65 QC 647 L1/L2, Gidds - 292, kWh - 22.6, Soc - 97.1%, Hx - 111.18%, Ahr - 64.38
June 25 '15: KM - 36 038, Soh - 100%, Charges - 67 QC 814 L1/L2, Gidds - 292, kWh - 22.6, Soc - 97.4, Hx - 99.62, Ahr - 64.38 / 62.68
Aug 31 '15: KM - 43441, Soh - 99%, Charges - 90 QC 939 L1/L2, Gidds - 291, kWh - 22.6, Soc - 97.5, Hx - 95.40%, Ahr - 61.73 / 60.19
Sep 7 '15: KM - 44171, Soh - 100%, Charges - 91 QC 948 L1/L2, Gidds - 292, kWh - 22.6, Soc - 97.2, Hx - 98.21%, Ahr - 63.90 / 62.14
Sep 25 '15: KM - 46180, Soh - 98%, Charges - 95 QC 980 L1/L2, Gidds - 288, kWh - 22.3, Soc - 97.4, Hx - 98.21%, Ahr - 61.10 / 59.53
Oct 4'15: KM - 47258, Soh - 100%, Charges - 100 QC 1000 L1/L2, Gidds - 291, kWh - 22.6, Soc - 97.1, Hx - 97.02%, Ahr - 62.93 / 61.09
Nov 15 '15: KM - 51224, Soh - 99%, Charges - 107 QC 1083 L1/L2, Gidds - 292, kWh - 22.6, Soc - 97.4, Hx - 95.91%, Ahr - 62.04 / 60.45


I would say if anything it's a combination of heat and quick charging. As you can see I've got over 107 QC on my car and was at a point in the winter where I was doing it 4-5 times a week. The other thing I did was that after it always had an L1 to at least 95% (most days over 100%) after I got to work. I never avoided the quick charge when it was warm but I didn't need it more than 2 times a week in the summer.

I've been doing L1 charges on the weekends now as the wife has stolen the leaf from me for daily driving and I've seen my SOH go back to 100%, Gids back to 292 and Ahr to 62.93/61.24

It isn't from the quick charging. I also have the same SOH 92% with a lizard battery installed in Arizona late December 2014. Lizard Car has only 7,000 miles on it since December about a year ago. I have 2 leafs. One with Lizard and one with original battery 8 Bar Car. They are having identical calendar losses (8%) but Lizard Car has driven roughly 4,400 miles less than 8 Bar Car. Read up on some of my related posts if you like.

LKK said:

Wasn't there a study performed by the Idaho National Lab that showed that degradation due to quick charging appears to have only minimal impacts? If I recall, they did an extensive test over an extended period driving Leafs that were QC and L2 charged side by side. I think the study showed that the QC least only suffered 5% more degradation. I believe that correlates to a slightly average battery temperature in the QC Leafs.

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There's been a couple threads on it, but I think this is the main one:
http://www.mynissanleaf.com/viewtopic.php?f=27&t=14271

and here's the report:
http://avt.inl.gov/pdf/energystorage/DCFC_Study_FactSheet_EOT.pdf

Page 2 is where it gets interesting. After 63k miles, the L2 cars got 64 miles per charge vs 58 for those only charged with DCQC for their life (at 45mph). To me that is a fairly minor difference.

It no longer matters in a moderate climate such as the U.K/ Ireland or similar climates.

The question is this, if the taxi hadn't so many fast charges then would it have more than 90% capacity ?

The Gen I battery wasn't nearly as good as the July Built 2013 + with the different battery, altered or whatever.

Nissan recommend not charging the leaf until the battery has cooled down and am nearly sure the manual says not to leave a hot battery at a high SOC.

Below is the 2nd gen Leaf 2013.

You might fail to realize a couple of things including that some of us have 2015 batteries in 2011 cars that are not holding up any better in the Arizona USA climate and other parts of our country because of hot temperatures. While I am very glad for others that do not suffer the same rapid degradation because of the climate that they reside in, it should still be noted that the more heat resistant chemistry is not working.

Luckily your climate and battery are doing as we all would like to see ours performing. Certainly your positive reporting is appreciated and acknowledged. I would be crowing from the rooftop too. Believe me I want to! We do not call 2013-15 2nd gen and I personally believe that 11-15's are going to prove out to be basically equal in durability when compared to each others stats in similar climates.

It does get me a little reactive when you suggest that the 13 (and newer?) battery is better that 11 and 12 when I have statistics that prove otherwise. I could see how you might believe that because your examples around you have not been subjected to the same seemingly tougher conditions.

For you to suggest that others are not taking care of their batteries as well, leads me to believe that you may need to dig into this further to see other facts and theories to satisfy your mind (on all of the possibilities) and it may come across to others as a little less insulting. I am happy for you and am not insulted, but I hope you are able to look at other cause and effect, and understand our reporting as well. Many of us don't have things proving to be as durable as what you are personally able to witness.

Evoforce said:

You might fail to realize a couple of things including that some of us have 2015 batteries in 2011 cars that are not holding up any better in the Arizona USA climate and other parts of our country because of hot temperatures. While I am very glad for others that do not suffer the same rapid degradation because of the climate that they reside in, it should still be noted that the more heat resistant chemistry is not working.

Luckily your climate and battery are doing as we all would like to see ours performing. Certainly your positive reporting is appreciated and acknowledged. I would be crowing from the rooftop too. Believe me I want to! We do not call 2013-15 2nd gen and I personally believe that 11-15's are going to prove out to be basically equal in durability when compared to each others stats in similar climates.

It does get me a little reactive when you suggest that the 13 (and newer?) battery is better that 11 and 12 when I have statistics that prove otherwise. I could see how you might believe that because your examples around you have not been subjected to the same seemingly tougher conditions.

For you to suggest that others are not taking care of their batteries as well, leads me to believe that you may need to dig into this further to see other facts and theories to satisfy your mind (on all of the possibilities) and it may come across to others as a little less insulting. I am happy for you and am not insulted, but I hope you are able to look at other cause and effect, and understand our reporting as well. Many of us don't have things proving to be as durable as what you are personally able to witness.

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I am not suggesting that the Battery is not able to withstand the heat of the hot climates in parts of the U.S, that's clearly evident that it's not.

For once will people just read what I type.

I was responding to the thread title which is "Frequent use of CHAdeMO DCQC Killing 2015 Leaf Battery? "

I responded with clear evidence that frequent quick charging does not kill the battery, as shown in my post above compared to the 2011- the updated leaf in July 2013 leafs. The original battery results were quiet different even in the climate of Ireland or the U.K and most likely all similar climates.

Now saying 1,788 DC charges has no impact could be wrong but it has very little impact compared to the early leaf but I would imagine in this case the 1,788 and 7,250 L2 charges are the real cause of the 10% loss.

Anyone who suggests there hasn't been a change to the batter from mid 2013 is ignoring the evidence and while it may have more heat resistance it's obviously not enough for very hot climates.

Small changes can have a big impact, more heat resistance and better cycling capability to better high current capability or C rate or just a litttle improvement to both.

What some of us are saying is that any changes that they have made appear to not have made a difference including the 2013 battery that you believe is better. And to your other point, QC and it's effect I also believe could possibly contribute to degradation in an already hot traction battery that pushes the temperatures into the red zone. Other than that, I am in agreement with you if you look at my earliest post in the thread. In your climate, you may never be able to heat your pack up that much. In my climate you can. Our observations are based on what we are experiencing and yours are what you are observing. I think we all agree that climate (hot) is obviously the most negative factor. The only tweak that Nissan admitted to, was to change chemistry to make them more heat tolerant for climates like Arizona. That is not proving out to be successful but I wish that it were.