Tuning the Battery Aging Model

[Pipcecil]

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

Also for interesting facts - 91 QCs and 3,114 L1/L2

I am assuming days in the sun is just at work (which it sits parked in the sun, sometimes some shade). It is more difficult to account weekend sun loading since its variable along with variable places (the sun loading from Waxahachie [closest to me] is fairly different than Dallas, my in-laws are in Waxahachie but we go closer to dallas for shopping, food, etc. making weekend trips harder to predict]). Although it still probably averages out to a full 5 days give or take in the sun.

Oddly enough, playing around with the model, using the closest city - Waxahachie - had a small % error off (like 2%). Using Dallas (closest to work) the capacity loss was pretty spot on (less than 1% I think). Which really shows that the city of use should be where most of the solar loading is occuring, especially when the solar calculations from Waxahachie to Dallas have a large difference in solar load.

[Stoaty]

Oddly enough, playing around with the model, using the closest city - Waxahachie - had a small % error off (like 2%). Using Dallas (closest to work) the capacity loss was pretty spot on (less than 1% I think). Which really shows that the city of use should be where most of the solar loading is occuring, especially when the solar calculations from Waxahachie to Dallas have a large difference in solar load.

Yup. Although I live next to Santa Monica, CA, my Leaf gets virtually all of its solar loading (and much hotter temperatures) in the San Fernando Valley for 40 hours per week. Using the closest city in the Valley, Van Nuys my current stats are as follows:

Predicted Loss: 17.00%

Actual Loss: 17.38%

If I use Santa Monica instead, the predicted loss is 2.5% too low.

[Pipcecil]

It looks like I am gunning for my 4-bar replacement pack. Based on the model, I should loose the 4th bar @ ~55,000 give or take. Thats 5k miles to spare and would occur end of April beginning of May. The only problem is the non-linear loss over the calender year - slower in winter and faster in the summer. Lets hope I make it!

[hjaime]

Manufactured - 04/11
Delivered - 8/25/11
P3227 update - 7/26/13
Location - San Diego, CA; Leaf spends mostly 6 days a week in a parking garage.
Miles/kwh - 4.1
Odometer - 27,030
Capacity - 53.39 (AHr from Leaf Spy), S0H=81%, Hx=64.79%, 11 bars capacity showing
899 L1/L2 charges, 0 QC
Date - 5/16/2014
Parked in sun - 1 days/week

[ranss12]

Don't know if you are still collecting reports, but I haven't seen one from Upstate New York so I thought I'd throw my data into the ring:

--Date of Manufacture Jan/12
--Date of Delivery April 10th, 2012
--Date of P3227 4/12/2014
--Geographic location - Bloomfield, NY. Daily commute to Rochester, NY (29 miles one way). I expect that the climate of Rochester is similar to Syracuse, NY.
--Average miles/kwh for the life of your Leaf 4.9 estimated
--Current odometer reading 40153
--Current AH capacity reading 57.20 (from LEAFDD)
Exact date you took current odometer reading and current AH capacity 05/31/2014
Days per week parked in the sun 3.5
--No DC quick charges

[DaveEV]

Latest data, just had 3rd annual battery report yesterday:

Manufactured - 4/11
Delivered - 6/7/11
P3227 update - 6/28/13
Location - Encinitas, CA (~3 mi inland)
Miles/kwh - 4.5
Odometer - 29300
Capacity - 53.40
Date - 6/13/13
Parked in sun - 5 days/week in Vista, CA (~7 mi inland).

Chart w/data since I've been able to track GIDs/Ah:

[Stoaty]

Latest data, just had 3rd annual battery report yesterday:

Manufactured - 4/11
Delivered - 6/7/11
P3227 update - 6/28/13
Location - Encinitas, CA (~3 mi inland)
Miles/kwh - 4.5
Odometer - 29300
Capacity - 53.40
Date - 6/13/13
Parked in sun - 5 days/week in Vista, CA (~7 mi inland).

Certainly looks like capacity loss is slowing (which is what I have observed), but need to see another 3-4 months of data (the coming summer) to be sure.

PS The Battery Aging Model shows the following:

Predicted loss - 17.87%
Actual Loss - 19.40%

Actual Minus Predicted - 1.52%

Some of the excess loss is likely to be due to the fact that it is probably a bit hotter 7 miles inland than "San Diego", which was the only choice in the Battery Aging Model in your area. Still, pretty close agreement with the model. I am beating the Battery Aging Model by 0.55% (taken on 3rd birthday of my Leaf).

[thimel]

Had my LEAF for three years now. So time for an update

Manufactured - 05/11
Delivered - 6/11/11
P3227 updte - 9/14/13
Location - Sunnyvale, CA (near San Jose)
Miles/kwh - 4.2
Odometer - 29,453
Capacity - 53.49
Date - 6/15/14
Parked in sun - 5 days/week in Palo Alto

[KJD]

Had my LEAF for three years now. So time for an update

Manufactured - 05/11
Delivered - 6/11/11
P3227 updte - 9/14/13
Location - Sunnyvale, CA (near San Jose)
Miles/kwh - 4.2
Odometer - 29,453
Capacity - 53.49
Date - 6/15/14
Parked in sun - 5 days/week in Palo Alto

Number of capacity bars lost ?
GID count ?

[Weatherman]

Manufactured - 04/12
Delivered - 7/8/12
Date of P3227 update - 7/13/2013
Location – Ft. Lauderdale, FL (temps are pretty uniform across the Miami-Ft. Lauderdale metropolitan area)
Miles/kwh – 4.0
Odometer – 10,300
Capacity – 55.46
Date - 9/9/13
Parked in sun - 5 days/week


Comment: battery temps tend to average, over the course of a 24-hour period, about 5 to 10F warmer than air temp due to battery charging and slow heat dissipation.

Update, as I approach the two-year mark:

Odometer – 14,500
Capacity – 51.80 (78.18%)
Date - 6/16/14
Parked in sun - 7 days/week

Doing just a little bit better than predicted, but that's only because I put so few miles on the car. Expect the second capacity bar to drop any day, now.