Stoaty
Posts: 4488
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Tuning the Battery Aging Model

Tue Sep 10, 2013 1:45 pm

Edit 10/19/13: Latest version of Battery Aging Model spreadsheet (1.00) is now on the Wiki:

http://www.mynissanleaf.com/wiki/index. ... ging_Model" onclick="window.open(this.href);return false;

Original post:

It has become evident that the battery aging model is probably too optimistic--probably because it was adjusted to match the graph shown to TickTock by one of the Nissan engineers. I have been thinking about how to calibrate the model to more accurately show expected capacity loss in various climates, and believe I have come up with an idea that may allow me to do that. In the past, we didn't have a good measure of capacity, but the recently available Amp-Hour reading obtainable from the LeafDD or Leaf Battery App looks like a pretty accurate measure of capacity. If we can gather enough readings from enough different climates, I may be able to calibrate the model.

Here is the data that is needed. Please post to this thread only if you have and are willing to share all of the data requested; otherwise it won't be useful.

--Date of Manufacture (month and year)
--Date of Delivery (month, day and year)
--Date of P3227 update, if needed (should be at least 6 weeks prior to reading data)
--Geographic location - be specific, must include city and state, otherwise data of no use (also include work location city and state and days Leaf spends at work if climate significantly different than home)
--Average miles/kwh for the life of your Leaf (your best guestimate OK)
--Current odometer reading (i.e. total miles your Leaf has been driven)
--Current AH capacity reading from LeafDD or Leaf Battery App
Exact date you took current odometer reading and current AH capacity
Days per week parked in the sun (fractional days OK)


Here is an example with my data:

Manufactured - 03/11
Delivered - 6/17/11
P3227 updte - 7/15/13
Location - West Los Angeles, CA; Leaf spends 4 days a week in Canoga Park, CA
Miles/kwh - 5.6
Odometer - 20720
Capacity - 57.07
Date - 9/10/13
Parked in sun - 4 days/week
Last edited by Stoaty on Fri Nov 01, 2013 9:54 pm, edited 6 times in total.
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

Weatherman
Posts: 916
Joined: Tue Aug 30, 2011 12:03 pm
Delivery Date: 08 Jul 2012
Leaf Number: 20922
Location: Weston, Florida

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 1:59 pm

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.
Last edited by Weatherman on Tue Sep 10, 2013 3:41 pm, edited 2 times in total.
2013 Crystal Red Volt
2012 SV Glacier Pearl LEAF; turned in 5/12/2015:18.6K Miles:50.13 AHr:10 bars, 24% gone

User avatar
mwalsh
Posts: 9644
Joined: Thu Apr 22, 2010 10:10 am
Delivery Date: 05 Jan 2011
Leaf Number: 0213
Location: Garden Grove, CA

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 2:03 pm

Manufactured - 11/10
Delivered - 1/5/11
P3227 update - No
Location - Garden Grove, CA; Leaf spends 4 days a week at border Redondo Beach/Hawthorne, CA
Miles/kwh - 4.9
Odometer - 33,700
Capacity (AHr) - 52.54
Date - 8/26/13
Parked in sun - 7 days/week

Will be getting a new set of readings tomorrow because I had a rather low gid count on the original Gidometer this morning (just 203/72.2% with a 100% charge).
Last edited by mwalsh on Tue Sep 10, 2013 2:35 pm, edited 1 time in total.
2011 Blue Ocean SL with 84,000 miles
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Stoaty
Posts: 4488
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 2:28 pm

Drees has pointed out that readings should only be included if the P3227 update has already been done at least 3 weeks prior to the reading. The reading will be much more accurate after the update and it takes several weeks for the AH to adjust to the proper level.

Original post updated to include this data. Please update your entry to include this data.
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

kolmstead
Posts: 479
Joined: Mon Aug 09, 2010 9:07 pm
Delivery Date: 15 Jan 2011
Leaf Number: 000257
Location: Ridgecrest, California (100 miles east of Bakersfield)

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 2:54 pm

Manufactured - 11/10
Delivered - 1/15/11
P3227 update - Not done
Location - Ridgecrest, CA. Car spends weekdays at China Lake NAS
Miles/kwh - 5.6 summer, 4.9 winter
Odometer - 23660
Capacity - 49.00 (74.69%)
Date - 9/10/13
Parked in sun - 4.5 days/week

Sorry about P3227; I won't get it until next January when I haul my LEAF
back to Palmdale for battery check.

Down two capacity bars right now. 100% charge 203 gids, 72.2%
Hoping to qualify for warranty battery replacement next fall.

-Karl

Stoaty
Posts: 4488
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 3:03 pm

Please don't enter your reading unless you have all of the requested data, including the P3227 update done at least 3 weeks ago (if it applies to your Leaf). I am not going to include data that uses the old and imprecise algorhythm to calculate capacity (and thus capacity bars).
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

ColumbiaRiverGorge
Posts: 200
Joined: Fri May 28, 2010 2:50 pm
Delivery Date: 06 Jul 2011
Leaf Number: 4992
Location: Hood River, OR

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 4:59 pm

Manufactured – 05/11
Delivered – 07/06/11
P3227 updte - 06/21/13
Location - Odell, OR (50-65 degree summer night time temps.); Leaf spends 5 days a week in The Dalles, OR (at least 10 degrees hotter, 80-100’s summer day time temps.)
Miles/kwh – 3.9 by Carwings (way too optimistic)
Odometer - 40,402
Capacity – 54.60, 12 bars
Date - 9/10/13
Parked in sun - 5 days/week

The last two summers I have had two ground fans blowing underneath the car all night long. This summer I have been parking outside from 7 PM to 7 AM with fans to get the battery temperatures down. 58 mile commute. 65 mph commute with 2000' up and down a day. 40 miles @ 65 mph, 10 miles @ 55 mph, & 8 miles at 25-40 mph.
VEGAN & 2011 LEAF Tesla M3 reserved.

opencar
Posts: 177
Joined: Thu Aug 19, 2010 7:31 am
Delivery Date: 01 Jun 2011
Location: San Diego Coastal

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 6:06 pm

thanks for doing this Stoaty, i think it will be very enlightening. unfortunately, i'll have to wait 3 wks before I report to you since i just had my P3227 update and temporarily gained 5 Ahr.
Stoaty wrote:Please don't enter your reading unless you have all of the requested data, including the P3227 update done at least 3 weeks ago (if it applies to your Leaf). I am not going to include data that uses the old and imprecise algorhythm to calculate capacity (and thus capacity bars).

Stoaty
Posts: 4488
Joined: Fri Jun 18, 2010 9:50 pm
Delivery Date: 12 Jun 2011
Leaf Number: 3871
Location: West Los Angeles

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 7:11 pm

opencar wrote:thanks for doing this Stoaty, i think it will be very enlightening. unfortunately, i'll have to wait 3 wks before I report to you since i just had my P3227 update and temporarily gained 5 Ahr.
I will try to calibrate the model if I can collect a total of about 40 reports (perhaps 10 each from 4 different climate zones: Seattle/Northeast, Los Angeles/Tennessee, Texas/Florida and good old Phoenix metro area). That doesn't mean I want to limit the data to certain locales, only that I need a good spread of climates to make sure it accurately predicts each area. Although my method suffers from having partial year data, meaning for example that 15 months could include 2 hot summers, I can expect that point to fall below the prediction, while 15 months including 2 winters should fall above the prediction. It isn't perfect, but I hope to be able to improve the accuracy of the model in places where it falls short. As I recall, the model very accurately predicted the capacity for the guy with 80,000 miles in Washington state. It seems to get less and less accurate as the average temperature goes up.
2011 Leaf with 62,000 miles given to Nephew
2013 Tesla Model S85 with 251 miles rated range at full charge
Leaf Spy Manual
Battery Aging Model Spreadsheet

User avatar
TomT
Posts: 10642
Joined: Sun Aug 08, 2010 12:09 pm
Delivery Date: 01 Mar 2011
Leaf Number: 000360
Location: California, now Georgia
Contact: Website

Re: Tuning the Battery Aging Model

Tue Sep 10, 2013 7:27 pm

Date of Manufacture: 1/11
Date of Delivery: 3/1/11
Date of P3227 update: 6/3/13
Geographic location: Garage and weekends: Granada Hills, CA 91344; Work (Mon-Fri 8am-5p) Santa Monica, CA
Average miles/kwh for the life of your Leaf: 4.4
Current odometer reading: 37,512
Current AH capacity reading from LeafDD or Leaf Battery App: 52.47
Exact date you took current odometer reading and current AH capacity: 9/10/13
Days per week parked in the sun (fractional days OK): 5 days for 8 hours each day (see work above)
Leaf SL 2011 to 2016, Volt Premier 2016 to 2019, and now:
2019 Model 3; LR, RWD, FSD, 19" Sport Wheels, silver/black; built 3/17/19, delivered 3/29/19.

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