Tuning the Battery Aging Model

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Pipcecil said:
Manufactured - 05/11
Delivered - 6/17/11
P3227 update - 6/24/13
Location - Midlothian, TX; Leaf spends 5 days a week in Arlington, TX
Miles/kwh - 4.0
Odometer - 51,040
Capacity - 45.76
Date - 1/28/14
Parked in sun - 5 days/week

Its my 3 year ownership anniversary so I will re-update my car:

Delivered - 6/17/11
P3227 update - 6/24/13
Location - Midlothian, TX; Leaf spends 5 days a week in Arlington, TX
Miles/kwh - 4.0
Odometer - 57,735
Capacity - 43.27
SOH - 65%
Hx - 44.89%
Date - 6/17/2014
Parked in sun - 5 days/week

Still only 3 capacity bars lost.
 
Manufactured - 03/11
Delivered - 5/6/11
P3227 update - 8/12/13
Location - Los Angeles, CA (Crescenta Valley)
Miles/kwh - 4.8
Odometer - 74,795
Capacity (Ahr) - 46.62
SOH - 71%
Hx - 50.38
Date - 6/17/2014
Parked in sun - 1 days/week
 
Here is an update 10 month later:

Manufactured - 06/11
Delivered - 3/13
P3227 update - 8/13
Location - Montreal, QC, Canada
Miles/kwh - 4.6 ( 7.5km/kwh )
Odometer - 19375 (31000km)
Capacity (Ahr) - 56.8
SOH - 86%
Hx - 72.35
Date - 7/7/2014
Parked in sun - 3 days/week
 
My update at 3 years old:

Manufactured: 05/11
Delivered: 07/11
P3227 update: 7/2013
Location: Porto, Portugal
Miles/kW.h: 3.5
Odometer: 47k miles
Capacity: 52,9Ahr
SOH: 80%
HX: 64%
Date: 7/15/2014
Parked in Sun: Never
 
Here is an update:


Delivered - 6/11
Odometer - 39400
Capacity (Ahr) - 43.11
SOH - 65%
Hx - 59.02
Date - 7/17/2014
Parked in sun - 5 days/week
 
My Leaf battery pack is weathering this summer very well so far. In the last 2 months I have only lost about 0.5 Ah of capacity. I am still running ahead of the battery aging model, which is very surprising to me since I expected to get behind during the summer and make up the difference the rest of the year:

Van Nuys
5.6 miles/kwh
mileage - 30930
Days in the sun - 4
capacity - 54.13 Ah
Date of reading - 7/24/13
Manufacture - 4/15/11
Delivered - 6/12/11

Predicted Loss - 18.83%
Actual Loss - 18.29%

Actual minus predicted loss = -0.54%

I believe that factors other than climate and mileage affect battery capacity. I have seen there are a couple of people in very similar climate getting battery replacement under warranty or close to it without having much higher mileage. My guess is that keeping average SOC low and driving very conservatively (5.6 miles/kwh) are helping preserve my capacity. However, I have no way to prove my hypothesis. Still on track for 6.5 years (another 3.5 years from now) to 70% capacity remaining.
 
Latest data:

Manufactured - 4/11
Delivered - 6/7/11
P3227 update - 6/28/13
Location - Encinitas, CA (~3 mi inland)
Miles/kwh - 4.5
Odometer - 30500
Capacity - 52.90
Date - 7/25/13
Parked in sun - 5 days/week

Capacity has dropped about 0.5 Ah in the last month and about 0.8 Ah over the last two months.
 
Have a Seattle area LEAFer with a bit of an outlier stat

https://www.facebook.com/groups/seattlenissanleaf/permalink/807971609234278/" onclick="window.open(this.href);return false;

has 18,200 miles after 3 years 2 months of ownership and has lost a bar.
 
It's been a bit over 11 weeks since the P3227 update and the capacity number seems to have stopped its dramatic plummet, so I thought I would finally post some numbers:

Manufactured - 06/11
Delivered - 3/16/12
P3227 update - 5/23/14
Location - Winchester, VA; Leaf spends its time parked in a garage which is often open except in Winter
Miles/kwh - 4.8
Odometer - 20,361
Capacity - 55.55
Date - 8/17/14
Parked in sun - 0 days/week

Vehicle reported loss - 16.15%
Predicted loss - 13.30%
Actual percent of predicted - 121.5%

A couple of notes:

- We have had about the coolest summer on record here, but the P3227 update has managed to "ruin the ride" these last couple of months!
- I took a trip last Friday similar to one I had done about this time of year in 2012. Conditions were similar. In 2012, I arrived at the destination 71 miles away about three miles after LBW. On Friday, I arrived at the destination after 69 miles with 34% SOC remaining. The point being that it sure didn't *feel* like I had lost 16% capacity since 2012; more like I had *gained* 16% capacity.
- OTOH, this winter was also the coldest one we have had in a long time. (Our PV array has been through four winters here and this was the first winter it ever recorded temperatures of 0F or below...and it did it 7 mornings this winter.) At sub-10F temperatures and with high winds, I once left the LEAF home for one 46-mile trip which I normally wouldn't even think twice about taking.

I guess I'll have to wait until next summer to see if my experience matches Stoaty's: rapid drop in reported capacity during the summer following P3227, but very little capacity drop the following summer.
 
I'm not very knowledgeable about this stuff, but since it was my 3 year ownership anniversary this week, I decided to get the Leaf Spy (lite version only) so I could put out some info about my car/area. For those not familiar with WA state, Pasco is in the hottest, driest part and routinely gets temps above 100 F and often above 110 F. This summer has been a bit hotter and longer than usual, but I'll have to wait until it's over to know for sure.

Date - 8/18/2014
11 capacity bars
Delivered - 8/18/11
P3227 update - 1/10/14
Location - Pasco, WA
Miles/kwh - 4.7 (I normally get 5.2 in summer and 2.5-4.0 in winter)
Odometer - 20,700
Capacity - 54.38 AHr
SOH - 82%
Hx - 67.29%
Parked in sun - 3 days/week (this one is tough since I normally bicycle through the summer and the car sits in an uninsulated garage. However, I still drive it for errands and get lazy at times. I also park outside at night in the summer to help cool the battery as much as possible. I also keep the battery between 40-60% SOC most of the time. However, now that I have LeafSpy, it appears that the outside cooling doesn't really help much, and the %SOC is higher than it would appear from just the number of battery bars)

I have no idea how this might help the Battery Aging Model since any close city (Seattle/Portland/Spokane) has a completely different thermal environment. If I were to guess, maybe I'm closer to Sacramento.
 
RegGuheert said:
Manufactured - 06/11
Delivered - 3/16/12
Miles/kwh - 4.8
Odometer - 20,361
Capacity - 55.55
Hx - 70.24
Reddy said:
Delivered - 8/18/11
Miles/kwh - 4.7 (I normally get 5.2 in summer and 2.5-4.0 in winter)
Odometer - 20,700
Capacity - 54.38 AHr
Hx - 67.29%
It's interesting how close our numbers are. Your VIN is about 900 cars newer than mine and our mileage is about the same. Your capacity is about 1Ah lower which is almost certainly due to higher temperatures and more time in the sun. The summer of 2012 was very hot here, but it was more moderate in 2013 and downright cool this summer.
 
Reddy said:
I'm not very knowledgeable about this stuff, but since it was my 3 year ownership anniversary this week, I decided to get the Leaf Spy (lite version only) so I could put out some info about my car/area. For those not familiar with WA state, Pasco is in the hottest, driest part and routinely gets temps above 100 F and often above 110 F. This summer has been a bit hotter and longer than usual, but I'll have to wait until it's over to know for sure.

Date - 8/18/2014
11 capacity bars
Delivered - 8/18/11
P3227 update - 1/10/14
Location - Pasco, WA
Miles/kwh - 4.7 (I normally get 5.2 in summer and 2.5-4.0 in winter)
Odometer - 20,700
Capacity - 54.38 AHr
SOH - 82%
Hx - 67.29%
Parked in sun - 3 days/week (this one is tough since I normally bicycle through the summer and the car sits in an uninsulated garage. However, I still drive it for errands and get lazy at times. I also park outside at night in the summer to help cool the battery as much as possible. I also keep the battery between 40-60% SOC most of the time. However, now that I have LeafSpy, it appears that the outside cooling doesn't really help much, and the %SOC is higher than it would appear from just the number of battery bars)

I have no idea how this might help the Battery Aging Model since any close city (Seattle/Portland/Spokane) has a completely different thermal environment. If I were to guess, maybe I'm closer to Sacramento.
Strange update: I just returned from a 1200 mi week long trip down the Oregon Coast using 25 quick charging events (most were from LBW to 70% or so). My LeafSpy data are now 55.16 AHr, 84% SOH and 69.27% Hx. I don't know if all of the "exercise" increased the battery capacity, but I cooked it pretty good on the first day of the trip from Kennewick to Astoria.
 
Date: 13 Sept 14
10 Capacity bars
Manf: 8/11
Delivered: 9/9/11
P3227 Update: ~July 13
Location: Palmdale CA (N. LA Co.)
Miles: 45,525
Miles/kWh: 3.7 summer with extensive A/C, 4.1 winter with occasional heating.
95.0000%
Capacity: 47.5731
H: 51.93
Parked in Sun: 3 days/wk 6 hrs during school term, 3 days/week ~2 hrs, 1 day/wk ~3 hrs. Balance of time in garage. Now always charge to 100% when in garage. Until losing the second capacity bar, 75% of time at 80%, 25% at 100%. QC appx 6 times to 90%.
 
Reddy said:
Strange update: I just returned from a 1200 mi week long trip down the Oregon Coast using 25 quick charging events (most were from LBW to 70% or so). My LeafSpy data are now 55.16 AHr, 84% SOH and 69.27% Hx. I don't know if all of the "exercise" increased the battery capacity, but I cooked it pretty good on the first day of the trip from Kennewick to Astoria.
Now our numbers are even closer. Mileage, capacity, everything. I'm at 21,900 miles and 55.22Ah. I still have all 12 capacity bars, but I don't think I'll keep the top one much longer.

FWIW, some of the MY2013 owners are reporting their capacity goes up after QCs:
DaveinOlyWA said:
i drive roughly 25-50 miles day for a week. each day, my ahr drops going from upper 66's to mid 63's. Each time, my SOC never drops below 50 %.

then next week comes. have 3 days of 90+ mile commutes. see small increase in ahr every day with big jump (1.81 ahr) happening on warmest day which also was day after longest commute (96 miles) Shortest commute for the week was 74 miles. I end up at 66.81 ahr from 63.73 ahr.

then comes 3 day weekend. back to driving 25- 40 miles a day and today my ahr is... hold on

is 64.24 ahr. now am i worried at the seemingly 4.6% loss of capacity? or actually not sure how we would measure this because one method would be ahr from 67.36 for new to 64.24 or we could use a much nicer option of 3.1 % loss due to having only 22 kwh instead of the new 22.7 kwh?

now, I present this as information and contend nothing simply because I really don't know what all this means
Computerizer said:
I just did a long trip (1,500 miles in total over 2 weeks) in my 2013 and observed the impact on my AHr / Hx / SOH / etc via Leaf Spy Pro.

I started out with AHr=62.13, SOH=95%, Hx=95.69%.

After two days with 4 or 5 short quick charges each, and about 400 miles of driving, I was at AHr=65.54, SOH=100%, Hx=100.26%.

Then I drove one or two quick charges per day for several days, and noticed the numbers going back down a bit.

Finally, a couple days ago I performed 7 quick charge sessions in less than 12 hours (and drove 275 miles in between). Then the next morning I did another 100 miles or so with 2 short quick charges. I ended up with AHr=64.93, SOH=99%, Hx=100.25%

Now that we're back home, I'm going to be driving my normal 25-30 miles per day and expect to see it fall quickly back to the 92-95% ranges.
stjohnh said:
My wife's early MY2013 jumped from 62.02 to 64.25 AHr after a QC in June this year. Over the next few days fell down to its usual 60-62 range. However, multiple QCs on other occasions have not resulted in any bump in AHr capacity. I don't have QC in my 2013 S, so don't have post QC data for that car, however, in May this year, my S did have an unexpected jump in AHr capacity, also from 60.87 to 64.33. Completely unexpected and capacity also dropped to the usual 60.5-62 range afterwards. Maybe some freak bug in a version of LeafSpy, since the bumps were about 1 month apart?
 
I believe that there is no real increase in capacity but rather that such activity temporarily creates an instrumentation error in the BMS... Experience has shown that the values will quickly return to what they were prior as the BMS relearns...

Reddy said:
I just returned from a 1200 mi week long trip down the Oregon Coast using 25 quick charging events (most were from LBW to 70% or so). My LeafSpy data are now 55.16 AHr, 84% SOH and 69.27% Hx. I don't know if all of the "exercise" increased the battery capacity, but I cooked it pretty good on the first day of the trip from Kennewick to Astoria.
 
It's definitely just instrumentation error. Either the car is reading low without QC, or it's reading high with QC.

I have noticed a small jump in Ah readings on my '11 after a QC, though nothing like what the later LEAFs seem to see - only 0.5 Ah at the most.
 
I've seen my SOH number go from 79% to 80% after a qc (as well as a small ~0.2Ah bump in capacity). I guess you could argue it's spilling over into stuff that's not "engineering data" but due to the large hysteresis I haven't lost my second bar yet. I came back down to the "regular" numbers after a few days.
 
Reddy said:
Reddy said:
I'm not very knowledgeable about this stuff, but since it was my 3 year ownership anniversary this week, I decided to get the Leaf Spy (lite version only) so I could put out some info about my car/area. For those not familiar with WA state, Pasco is in the hottest, driest part and routinely gets temps above 100 F and often above 110 F. This summer has been a bit hotter and longer than usual, but I'll have to wait until it's over to know for sure.

Date - 8/18/2014
11 capacity bars
Delivered - 8/18/11
P3227 update - 1/10/14
Location - Pasco, WA
Miles/kwh - 4.7 (I normally get 5.2 in summer and 2.5-4.0 in winter)
Odometer - 20,700
Capacity - 54.38 AHr
SOH - 82%
Hx - 67.29%
Parked in sun - 3 days/week (this one is tough since I normally bicycle through the summer and the car sits in an uninsulated garage. However, I still drive it for errands and get lazy at times. I also park outside at night in the summer to help cool the battery as much as possible. I also keep the battery between 40-60% SOC most of the time. However, now that I have LeafSpy, it appears that the outside cooling doesn't really help much, and the %SOC is higher than it would appear from just the number of battery bars)

I have no idea how this might help the Battery Aging Model since any close city (Seattle/Portland/Spokane) has a completely different thermal environment. If I were to guess, maybe I'm closer to Sacramento.
Strange update: I just returned from a 1200 mi week long trip down the Oregon Coast using 25 quick charging events (most were from LBW to 70% or so). My LeafSpy data are now 55.16 AHr, 84% SOH and 69.27% Hx. I don't know if all of the "exercise" increased the battery capacity, but I cooked it pretty good on the first day of the trip from Kennewick to Astoria.

your battery simply realized that you needed more range due to your increased driving and was more than willing to oblige!

http://daveinolywa.blogspot.com/2014/09/manipulating-battery-stats.html" onclick="window.open(this.href);return false;
 
DaveinOlyWA said:
your battery simply realized that you needed more range due to your increased driving and was more than willing to oblige!
Ha! I certainly needed it on the trip back, 85 mi from Arlington, OR to the Tri-Cities! I skipped my backup charge at 70 mi (and 4 mi past LBW) and cruised back down hill to the river, drove 25 mph in the park and arrived home about 6 mi past VLBW. I think I was still around 9% SOC on LeafSpy so wasn't "too" worried. It would have been fairly ironic to finish a 1200 mi trip and fall short a mile or two from home.
 
Update on my 3 year old leaf:
Date - 9/22/2014
10 capacity bars as of 9/01/2014

Delivered - August 2011

Location - San Diego, CA
Miles/kwh - 3.8 (normally get 4.1 in winter)
Odometer - 30,655
Capacity - 51.35 AHr
SOH - 78%
Hx - 59.87%

Parked in sun occasionally on weekends. Hot summer this year seems to have accelerated capacity loss by a bar. Lost first bar in Dec 2013, since then, mostly charge to 80% and rarely drop below 20% charge.

Glad to hear we can purchase a new battery now!
 
Back
Top