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I suspect that the QCs are the explanation for both the good stats and the odd drops. There is evidence, with past Leafs, that frequent QC sessions inflate the SOH. Those periodic drops may be the BMS suddenly "realizing" that it's been fooled by them...
 
Astros said:
My stats, on a 2018 SV bought last April:

~13000 miles
43 L3
252 L2
AHr 109.92
SOH 95.22%
Hx 114.63%
Driven mostly in Western Washington.

I track the stats roughly once a week, and have seen almost all of the degradation happen over three sudden drops, spaced every ~90 days. One of those drops happened during a long trip in the summer, but another one happened over the course of a few hours on a cool evening with only a few miles driven around town.


Ok, guessing I know of you in another life but have you seen my blog? I did a rather extensive one year review and the last part on degradation you might find interesting. Pay close attention to the last chart when I charted my stats every 1000 miles. The first drop was only 58 days after delivery but only tells me when I car was built and first tested. It had 4 QCs on it when I picked it up.

https://daveinolywa.blogspot.com/2019/03/happy-birthday-leaf.html
 
DaveinOlyWA said:
Ok, guessing I know of you in another life but have you seen my blog? I did a rather extensive one year review and the last part on degradation you might find interesting. Pay close attention to the last chart when I charted my stats every 1000 miles. The first drop was only 58 days after delivery but only tells me when I car was built and first tested. It had 4 QCs on it when I picked it up.

Yep, I follow your blog, and the drops you've seen are very similar to mine. Excluding those drops the degradation according to LeafSpy is modeled almost perfectly by a double linear fit, with nearly no scatter. That fit is a degradation rate of 3.1 aHr/10,000 miles for the first 7,000 miles, slowing to a rate of 0.9 aHr/10,000 miles after that. The drops were 0.8 aHr at 1,499 miles (~1 month), 0.4 aHr at 5,700 miles (~4 months), and 1.0 aHr at 10,000 miles (~7 months).

I realize now that I misstated my drops earlier, because what I wrote in my earlier post was the cumulative drop. So, unfortunately the drops are not actually getting smaller.
 
Astros said:
DaveinOlyWA said:
Ok, guessing I know of you in another life but have you seen my blog? I did a rather extensive one year review and the last part on degradation you might find interesting. Pay close attention to the last chart when I charted my stats every 1000 miles. The first drop was only 58 days after delivery but only tells me when I car was built and first tested. It had 4 QCs on it when I picked it up.

Yep, I follow your blog, and the drops you've seen are very similar to mine. Excluding those drops the degradation according to LeafSpy is modeled almost perfectly by a double linear fit, with nearly no scatter. That fit is a degradation rate of 3.1 aHr/10,000 miles for the first 7,000 miles, slowing to a rate of 0.9 aHr/10,000 miles after that. The drops were 0.8 aHr at 1,499 miles (~1 month), 0.4 aHr at 5,700 miles (~4 months), and 1.0 aHr at 10,000 miles (~7 months).

I realize now that I misstated my drops earlier, because what I wrote in my earlier post was the cumulative drop. So, unfortunately the drops are not actually getting smaller.

My last drop was the largest and also took the longest taking a week. Larger drops do make sense as the pack capacity shrinks, what remains must work harder. But as mentioned above, I am not fully invested in my trust of the BMS...
 
Just leased a 2018 SV today. I'll try to keep track of the degradation over time. It has a build date of 2/18 so it's probably been sitting on the lot about a year.

Here are the initial stats, about what I'd expect after a year on the lot.

odo = 104mi
SOH = 97.47%
AHr = 112.52
Hx = 99.35%
QC =7
L1/L2 = 7
 
My sig below reports when I purchased the 18 MY.
As it was driven for the last few months in cool conditions, I'm interested to see what it will look like after the summer:

SOH: 96.7 pct
Ahr: 111.94
Odo: 3,900 miles
Hx: 115.78 pct
QC: 30
L2: 100

Random question: why does the leafspy app show my odo at 2,400 miles when clearly I've driven 3,900???
 
jdcbomb said:
Random question: why does the leafspy app show my odo at 2,400 miles when clearly I've driven 3,900???

Just a guess but 3900/2400 is about equal to 1 mile/1 km. I don't know if there is a mile/km setting somewhere that is off but that is where I'd look first.
 
goldbrick said:
jdcbomb said:
Random question: why does the leafspy app show my odo at 2,400 miles when clearly I've driven 3,900???

Just a guess but 3900/2400 is about equal to 1 mile/1 km. I don't know if there is a mile/km setting somewhere that is off but that is where I'd look first.

Yea I thought so at first, but looked in settings, and it clearly has "miles" selected. Therefore, I can only guess I should toggle it to KM and back MI and see what happens. Otherwise, maybe the lite version of this helpful app has a bad km/mi setting.
 
Well, one year to the day after driving my 2018 SL home last April, I did another LeafSpy reading, albeit with only about 58% charge. I was pleasantly surprised, and I also realized that I had transposed two digits in my mind from the last reading. I'll repeat it with 100% SOC tomorrow, if possible.

SOC = 58.5

GIDs = 288

SOH = 96.44%

Hx = 105.28%

AH = 111.33

Voltage Difference = 26mv

18 QCs

63 L-1/L-2 Charges

There is definitely some good news here. While the pack lost 3.45% capacity during the first five months or so, it only lost another 0.11% over the Winter and early Spring, if the BMS is to be believed. I hope that it is!

If correct, the indication here is that the 40kwh pack retains the resistance to "calendar aging" exhibited by the "Lizard Pack" but has somewhat less resistance to heat. My car was babied last Summer: I kept it in an air-conditioned garage when temps were high both day and night, and sometimes when only daytime temps were high. When the A/C wasn't in use I used a ventilation fan on a timer to cool the garage during the cooler nights. I did use the car a few times on 90F+ days, but by starting with a cool pack I don't believe I ever saw more than about 7 temp "bars" (which, with no delineated segments are now harder to read) and usually not more than 6. It will be interesting to see figures from cars that saw much more prolonged heating last Year.
 
LeftieBiker said:
Well, one year to the day after driving my 2018 SL home last April, I did another LeafSpy reading, albeit with only about 58% charge. I was pleasantly surprised, and I also realized that I had transposed two digits in my mind from the last reading. I'll repeat it with 100% SOC tomorrow, if possible.

SOC = 58.5

GIDs = 288

SOH = 96.44%

Hx = 105.28%

AH = 111.33

Voltage Difference = 26mv

18 QCs

63 L-1/L-2 Charges

There is definitely some good news here. While the pack lost 3.45% capacity during the first five months or so, it only lost another 0.11% over the Winter and early Spring, if the BMS is to believed. I hope that it is!

If correct, the indication here is that the 40kwh pack retains the resistance to "calendar aging" exhibited by the "Lizard Pack" but has somewhat less resistance to heat. My car was babied last Summer: I kept it in an air-conditioned garage when temps were high both day and night, and sometimes when only daytime temps were high. When the A/C wasn't in use I used a ventilation fan on a timer to cool the garage during the cooler nights. I did use the car a few times on 90F+ days, but by starting with a cool pack I don't believe I ever saw more than about 7 temp "bars" (which, with no delineated segments are now harder to read) and usually not more than 6. It will be interesting to see figures from cars that saw much more prolonged heating last Year.


81 charging events in a year? Is that right?
 
This is my battery at 7 months & about 10,500 miles in:

Iw2BcwA.png



So 99.2% when about 2 weeks old vs 96.54% at seven months. 2.66% drop half way into the 1st year seems respectable especially considering the mileage but let's see how it weathers the summer; pun intended...
 
LeftieBiker said:
Well, one year to the day after driving my 2018 SL home last April, I did another LeafSpy reading, albeit with only about 58% charge. I was pleasantly surprised, and I also realized that I had transposed two digits in my mind from the last reading. I'll repeat it with 100% SOC tomorrow, if possible.

SOC = 58.5

GIDs = 288

SOH = 96.44%

Hx = 105.28%

AH = 111.33

Voltage Difference = 26mv

18 QCs

63 L-1/L-2 Charges

There is definitely some good news here. While the pack lost 3.45% capacity during the first five months or so, it only lost another 0.11% over the Winter and early Spring, if the BMS is to be believed. I hope that it is!

If correct, the indication here is that the 40kwh pack retains the resistance to "calendar aging" exhibited by the "Lizard Pack" but has somewhat less resistance to heat. My car was babied last Summer: I kept it in an air-conditioned garage when temps were high both day and night, and sometimes when only daytime temps were high. When the A/C wasn't in use I used a ventilation fan on a timer to cool the garage during the cooler nights. I did use the car a few times on 90F+ days, but by starting with a cool pack I don't believe I ever saw more than about 7 temp "bars" (which, with no delineated segments are now harder to read) and usually not more than 6. It will be interesting to see figures from cars that saw much more prolonged heating last Year.

That's great! Very encouraging.
 
goldbrick said:
Why does LeafSpy show the odo at 6784 miles? Was this a recent shot?

That photo was taken April 16th. LeafSpy has never displayed the correct odometer reading for me. It's always been about 55% of actual miles.


Check out what I mean. I just took this photo:

Rqlr4Pl.jpg


In other "sad" news I apparently lost another .09 SOH in the last two weeks...
 
^^^
I wonder if the Leaf Spy/dash odometer wonkiness is due to a km vs. mile issue.

11604 / 7210 = 1.609
1 mile is 1.609 km.

As for the SOH loss or whatever… I wouldn’t worry about it. At least on gen 1 Leafs, it fluctuates and can be manipulated up and down somewhat.
 
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