Requesting Hx values for all 40/62 kwh LEAFers

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DaveinOlyWA

Well-known member
Joined
Apr 24, 2010
Messages
16,260
Location
Olympia, WA
There is probably no real consensus of what Hx is but after reviewing several LS shots of 40 kwh LEAFs, a pattern is emerging.

When Hx is low (around 100%), degradation rates are low.

When Hx is high (around 118-120%) degradation rates are high.

So I am looking for LEAFs that counter this observation.
 
If this pans out, it may provide a way to detect better packs on a dealership lot.

Last SOH (end of April): 91.69%

Last SOH: 106.56% (I think they threw the % sign in just to mess with us.)
 
2019 SL Plus
Manufactured 07/2019
Purchased 08/10/2019
175.15 AHr
99.29% SOH
98.19% Hx
QC=1; L1/L2=6
64 miles at initial Leaf Spy reading on 8/11/2019

173.22 AHr (172.27)
98.20% SOH (97.66%)
112.45% Hx (112.00%)
QC=2; L1/L2=43
4,383 miles after first 90-day adjustment on 10/25/2019

173.19 AHr (172.70)
98.18% SOH (97.90%)
114.02% Hx (113.99%)
QC=2; L1/L2= 80
10,160 miles after second 90-day adjustment on 1/22/2020

171.78 AHr (172.66)
97.38% SOH (97.88%)
113.11% Hx (113.19%)
QC=4; L1/L2=108
15,073 miles after third 90-day adjustment on 4/23/2020

170.90 AHr
96.88% SOH
109.93% Hx
QC=4; L1/L2=122
17,200 miles tonight
I have been teleworking since March 6th so less highway driving, less miles per day, more days between charges, and SOC is high when car is parked the first day after charging. Numbers in parentheses are values before adjustment so you can see the first two adjustments were upward while last was downward. It will be interesting to see how the numbers change if I ever get back to my "old normal" use pattern.
 
LeftieBiker said:
Gerry is an exception, it seems.

Maybe... One thing I notice is it takes several months just to get to your "equilibrium Hx. We all start in the mid to upper 90's then rise. I peaked at 117.15 and now at 113.44 as of this morning.

I also charted my rise and noticed early the rises averaged between .20 -.30 normally driving 15-30 miles a day but then I saw bigger jumps;

99.53-100.38 driving 56 miles
100.28-101.56 driving 97 miles
107.65-109.11 driving 377 miles

So I get to around 112 and I am static for a few weeks then my first adjustment happened and its a big one (over 2.5% loss) lasting 9 days and Hx goes from 112.79 to 113.95 during that period with all days between 11.3 to 26.7 miles with 7 of the 9 days between 20.3 and 26.7 miles

Early on, a DC session also happened on the big jump days (more than .5%)
 
GerryAZ said:
2019 SL Plus
Manufactured 07/2019
Purchased 08/10/2019
175.15 AHr
99.29% SOH
98.19% Hx
QC=1; L1/L2=6
64 miles at initial Leaf Spy reading on 8/11/2019

173.22 AHr (172.27)
98.20% SOH (97.66%)
112.45% Hx (112.00%)
QC=2; L1/L2=43
4,383 miles after first 90-day adjustment on 10/25/2019

173.19 AHr (172.70)
98.18% SOH (97.90%)
114.02% Hx (113.99%)
QC=2; L1/L2= 80
10,160 miles after second 90-day adjustment on 1/22/2020

171.78 AHr (172.66)
97.38% SOH (97.88%)
113.11% Hx (113.19%)
QC=4; L1/L2=108
15,073 miles after third 90-day adjustment on 4/23/2020

170.90 AHr
96.88% SOH
109.93% Hx
QC=4; L1/L2=122
17,200 miles tonight
I have been teleworking since March 6th so less highway driving, less miles per day, more days between charges, and SOC is high when car is parked the first day after charging. Numbers in parentheses are values before adjustment so you can see the first two adjustments were upward while last was downward. It will be interesting to see how the numbers change if I ever get back to my "old normal" use pattern.

Yours is interesting on a few different observations. You did have upward adjusting numbers but your daily drops on first adjustment were higher. Your dailies dropped 1.39% on first adj. .30 on 2nd, .30 on the 3rd, but already .5 on the 4th barely halfway to #4.


So, buy in August, big daily drops but upwards bump in Oct (starting to get cooler?? I don't remember it being very cool in October when I lived there 4 decades ago. Was the weather cooler than normal?)

Go thru 2 adjustments in Winter. small ones. Now as Summer swings in, one way to "larger" adjustment.

So seems like your car might be affected by heat but it simply has to be the extreme kind since others in "warm" areas don't seem to be...at least not to the degree of Gen 1 LEAFs.

Also wondering how your charging habits are playing a part. It "shouldn't" be good but hard to argue that point at this time.
 
DaveinOlyWA said:
There is probably no real consensus of what Hx is

Correct, for Leaf2. Although it's highly correlated with the degradation of the conductance (reciprocal of battery resistance) for Leaf1 over time.
It tracks SOH for Leaf1 vehicles.

DaveinOlyWA said:
but after reviewing several LS shots of 40 kwh LEAFs, a pattern is emerging.

A total waste of time. Like trying to find correlation from a random number generator. Have fun, though!
 
This is all so fascinating.

Any other late built 2019 Plus or 2020 plus owners out there that can post their LeafSpy data? Any chance they made a software change towards the end of last year?

Another interesting thing I am noticing is that my efficiency of driving this summer so far has been significantly above last summer (approx .3-.4). Now tires will be worn a bit, which helps, but its created the effect of having just about the same GOM values as last summer. My GIDs as way less though (720 now vs. 765-775 new).
 
evtifosi said:
6/10/20

2018 LEAF
AHr=104.93
SOH=90.90%
HX=95.33%

Interestingly, when the car was delivered to us on Monday from the dealer it had a HX of 114%...

We have driven it twice around 20 miles...

Your Hx dropped from 114 to 95.53? Are you sure it wasn't the ahr that dropped from 114? How long did it sit on the lot before you bought it?
 
DaveinOlyWA said:
GerryAZ said:
2019 SL Plus
Manufactured 07/2019
Purchased 08/10/2019
175.15 AHr
99.29% SOH
98.19% Hx
QC=1; L1/L2=6
64 miles at initial Leaf Spy reading on 8/11/2019

173.22 AHr (172.27)
98.20% SOH (97.66%)
112.45% Hx (112.00%)
QC=2; L1/L2=43
4,383 miles after first 90-day adjustment on 10/25/2019

173.19 AHr (172.70)
98.18% SOH (97.90%)
114.02% Hx (113.99%)
QC=2; L1/L2= 80
10,160 miles after second 90-day adjustment on 1/22/2020

171.78 AHr (172.66)
97.38% SOH (97.88%)
113.11% Hx (113.19%)
QC=4; L1/L2=108
15,073 miles after third 90-day adjustment on 4/23/2020

170.90 AHr
96.88% SOH
109.93% Hx
QC=4; L1/L2=122
17,200 miles tonight
I have been teleworking since March 6th so less highway driving, less miles per day, more days between charges, and SOC is high when car is parked the first day after charging. Numbers in parentheses are values before adjustment so you can see the first two adjustments were upward while last was downward. It will be interesting to see how the numbers change if I ever get back to my "old normal" use pattern.

Yours is interesting on a few different observations. You did have upward adjusting numbers but your daily drops on first adjustment were higher. Your dailies dropped 1.39% on first adj. .30 on 2nd, .30 on the 3rd, but already .5 on the 4th barely halfway to #4.


So, buy in August, big daily drops but upwards bump in Oct (starting to get cooler?? I don't remember it being very cool in October when I lived there 4 decades ago. Was the weather cooler than normal?)

Go thru 2 adjustments in Winter. small ones. Now as Summer swings in, one way to "larger" adjustment.

So seems like your car might be affected by heat but it simply has to be the extreme kind since others in "warm" areas don't seem to be...at least not to the degree of Gen 1 LEAFs.

Also wondering how your charging habits are playing a part. It "shouldn't" be good but hard to argue that point at this time.

Reduced driving (especially reduced freeway driving) seem to be most noticeable cause of falling numbers for AHr and SOH. The car sat for over 2 weeks at the airport while I was on a motorcycle trip in Alaska and Canada during the last half of August and early September so that helps to explain the early loss. This spring was relatively cool so temperature does not explain the drop in April--again reduced daily miles and greatly reduced freeway driving after March 5 appear to be main factors. Also, there are a few cells that appear weak when looking at the cell voltage graphs at nearly full charge or nearly depleted (very low battery warning or lower) so that could be influencing the numbers, but does not seem to have significant impact to energy storage capability.
 
The Incredible Shinking SOH

2020 SL plus built 12/19
delivered Feb 27 2020
Initial SOH  99.36 Hx 98.18 AHr 175.27
March 29    99.31 98.48
April 30       99.21 99.28
May 31        99.08 99.89
June 2         98.65
June 5         98.15 99.94
June 6         97.37 99.89 AHr 171.76
June 7         97.09
June 8         97.02 
June 10       96.66 99.92 AHr 170.51
June 11       96.23
June 12       95.95 99.92 AHr 168.89
June 13       95.59
June 14 95.38 99.92 AHr 168.25

ODO 1828
Except for SOC of 90% at dealership on pickup
Leaf has always been charged to less than 80%
and remained above 30% so far.
It took more than 5 months to show a significant drop
but now...this seems to be a wowser.
Maybe a bms algorithm fault?  Will the slide stop?
Any thoughts on what might be happening?
 
Blueflex2 said:
The Incredible Shinking SOH

2020 SL plus built 12/19
delivered Feb 27 2020
Initial SOH  99.36 Hx 98.18 AHr 175.27
March 29    99.31 98.48
April 30       99.21 99.28
May 31        99.08 99.89
June 2         98.65
June 5         98.15 99.94
June 6         97.37 99.89 AHr 171.76
June 7         97.09
June 8         97.02 
June 10       96.66 99.92 AHr 170.51
June 11       96.23
June 12       95.95 99.92 AHr 168.89
June 13       95.59
June 14 95.38 99.92 AHr 168.25

ODO 1828
Except for SOC of 90% at dealership on pickup
Leaf has always been charged to less than 80%
and remained above 30% so far.
It took more than 5 months to show a significant drop
but now...this seems to be a wowser.
Maybe a bms algorithm fault?  Will the slide stop?
Any thoughts on what might be happening?

Don't waste time gathering Hx data, Hx is meaningless for Leaf2. The key data are SOH & Ahr.
 
DaveinOlyWA said:
There is probably no real consensus of what Hx is but after reviewing several LS shots of 40 kwh LEAFs, a pattern is emerging.

When Hx is low (around 100%), degradation rates are low.

When Hx is high (around 118-120%) degradation rates are high.

So I am looking for LEAFs that counter this observation.
Only a personal hunch from observing my 40KWh every 5,000 miles, sense it's related to either battery temp or ambient temps (or some factor of both). I typically catch my readings in the early morning after charging L2 to 100% overnight. Mine have held steady @ 115% during warmer weather, climbed to 121% in the dead of winter, then dropped when the weather warmed. Maybe an odd situation because was on medical leave from late January into early March, and not commuting or charging daily so the battery was relatively cold most of this past winter.
 
Blueflex, we are all trying to figure out the buffering algorithm Nissan has in place.

The oldest Plus models are 15 months old. We are trying to see as many data points as possible. The first major adjustment does seems to be 6 months post build.
 
lorenfb said:
Blueflex2 said:
The Incredible Shinking SOH

2020 SL plus built 12/19
delivered Feb 27 2020
Initial SOH  99.36 Hx 98.18 AHr 175.27
March 29    99.31 98.48
April 30       99.21 99.28
May 31        99.08 99.89
June 2         98.65
June 5         98.15 99.94
June 6         97.37 99.89 AHr 171.76
June 7         97.09
June 8         97.02 
June 10       96.66 99.92 AHr 170.51
June 11       96.23
June 12       95.95 99.92 AHr 168.89
June 13       95.59
June 14 95.38 99.92 AHr 168.25

ODO 1828
Except for SOC of 90% at dealership on pickup
Leaf has always been charged to less than 80%
and remained above 30% so far.
It took more than 5 months to show a significant drop
but now...this seems to be a wowser.
Maybe a bms algorithm fault?  Will the slide stop?
Any thoughts on what might be happening?

Don't waste time gathering Hx data, Hx is meaningless for Leaf2. The key data are SOH & Ahr.

Who is wasting who's time here?

Besides he isn't doing anything, I am.
 
Blueflex2 said:
The Incredible Shinking SOH

2020 SL plus built 12/19
delivered Feb 27 2020
Initial SOH  99.36 Hx 98.18 AHr 175.27
March 29    99.31 98.48
April 30       99.21 99.28
May 31        99.08 99.89
June 2         98.65
June 5         98.15 99.94
June 6         97.37 99.89 AHr 171.76
June 7         97.09
June 8         97.02 
June 10       96.66 99.92 AHr 170.51
June 11       96.23
June 12       95.95 99.92 AHr 168.89
June 13       95.59
June 14 95.38 99.92 AHr 168.25

ODO 1828
Except for SOC of 90% at dealership on pickup
Leaf has always been charged to less than 80%
and remained above 30% so far.
It took more than 5 months to show a significant drop
but now...this seems to be a wowser.
Maybe a bms algorithm fault?  Will the slide stop?
Any thoughts on what might be happening?

Ok, guessing you don't DC at all? So you are averaging just over 400 miles a month? How often do you charge? Your Hx is low but I have a sneaking suspicion its due to lack of activity.
 
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