Lost Battery Capacity and Range / Autonomy, Page 2

[TonyWilliams]

Forgive me for being a new Leaf owner and asking this question, but is the 86 degree a target for air temp while the car is being driven or charged, or apply to while it is parked as well? Should the windows be cracked and a window shade be used to keep in car temps down while parked or am I on the wrong wavelength here? I just leased our 2013 Leaf S 10 days ago, and have it set to charge at 80% during the week, and 100% on fridays when leaving the charging station at work.

And so I'm clear, the 2013 Leaf battery is not liquid cooled?
Also, have there been any software updates or revisions on the 2013's that differ from the orig Leafs? I know my Leaf is supposed to cut power output of the battery pack in higher temps. Was that the case with the orig Leaf in 2011?

We live in San Diego a mile from the beach. Commute in the morn is not a prob, daytime temps at work in summer are approx 80-88 degrees during the summer. By the 5 or 6pm commute even in summer, the temps should have dropped to at least the high 70's. =)

In San Diego coastal areas, I wouldn't spend much time thinking about heat. Yes, the battery will absolutely degrade, but at a much slower rate than Phoenix. My very simple rule of thumb is 10% loss in 6-18 months, then 3-4% each year after for San Diego.

No, the LEAF battery has no cooling system.

 

[scottf200]

April 10, 2013 - http://portal.acs.org/portal/acs/corg/content?_nfpb=true&_pageLabel=PP_ARTICLEMAIN&node_id=222&content_id=CNBP_032579&use_sec=true&sec_url_var=region1&__uuid=59fb4e16-24a7-4200-b6ff-cf3bb98e1607" onclick="window.open(this.href);return false;
"How long a battery pack lasts in an electric or hybrid vehicle depends on many factors. Mikael G. Cugnet, Ph.D, explained that the lifespan depends mainly on the battery’s temperature, state of charge and charge protocol. Battery performance begins to suffer as soon as the temperature climbs above 86 degrees Fahrenheit. “The higher the temperature, the lower the battery service life,” he said. “A temperature above 86 degrees F affects the battery pack performance instantly and even permanently if it lasts many months like in Middle East countries.”

86F matches what one observed the Volt limiting: volt-battery-thermal-management-system-in-the-hot-arizona-sun http://gm-volt.com/2013/05/03/volt-battery-thermal-management-system-in-the-hot-arizona-sun/" onclick="window.open(this.href);return false;

 

[planet4ever]

Forgive me for being a new Leaf owner and asking this question, but is the 86 degree a target for air temp while the car is being driven or charged, or apply to while it is parked as well? Should the windows be cracked and a window shade be used to keep in car temps down while parked or am I on the wrong wavelength here?

Yes, the battery temperature matters when the car is parked, but it changes temperature slowly. So if the battery starts the day at 80°F (for example) and bakes all day when the ambient temperature rises to 90°F in the afternoon, then the battery probably won't get much over 85°F (just a guess on my part).

As for cracking windows or using a shade, those will help the cabin temperature, and so indirectly might put a bit less load on the battery from running the air conditioner, but they won't affect the battery temperature directly. Parking on very hot asphalt would, though.

Ray

 

[thankyouOB]

In San Diego coastal areas, I wouldn't spend much time thinking about heat. Yes, the battery will absolutely degrade, but at a much slower rate than Phoenix. My very simple rule of thumb is 10% loss in 6-18 months, then 3-4% each year after for San Diego.

is this estimate or guesstimate based on data from more than 1 or 2 cars?

 

[DaveinOlyWA]

Forgive me for being a new Leaf owner and asking this question, but is the 86 degree a target for air temp while the car is being driven or charged, or apply to while it is parked as well? Should the windows be cracked and a window shade be used to keep in car temps down while parked or am I on the wrong wavelength here? I just leased our 2013 Leaf S 10 days ago, and have it set to charge at 80% during the week, and 100% on fridays when leaving the charging station at work.

And so I'm clear, the 2013 Leaf battery is not liquid cooled?
Also, have there been any software updates or revisions on the 2013's that differ from the orig Leafs? I know my Leaf is supposed to cut power output of the battery pack in higher temps. Was that the case with the orig Leaf in 2011?

We live in San Diego a mile from the beach. Commute in the morn is not a prob, daytime temps at work in summer are approx 80-88 degrees during the summer. By the 5 or 6pm commute even in summer, the temps should have dropped to at least the high 70's. =)

you want to stay as cool as possible and if targeting a temperature is possible, I would go with 70º as the ultimate.

another thing you want to consider is the difference between the air temperature and surface temperatures. iow, a sunny cool day can raise the temperature of the battery much higher than than the air temperature. so, park in shade as much as possible.

 

[TonyWilliams]

In San Diego coastal areas, I wouldn't spend much time thinking about heat. Yes, the battery will absolutely degrade, but at a much slower rate than Phoenix. My very simple rule of thumb is 10% loss in 6-18 months, then 3-4% each year after for San Diego.

is this estimate or guesstimate based on data from more than 1 or 2 cars?

It's pure SWAG based on anecdotes.

The "Sloaty" model is far better.

 

[Stoaty]

It's pure SWAG based on anecdotes.

The "Stoaty" model is far better.

You can read about and download the Battery Aging Model ("Stoaty" model - developed by Surfingslovak, refined and fleshed out by Stoaty) here:

http://www.mynissanleaf.com/wiki/index.php?title=Battery_Capacity_Loss#Battery_Aging_Model" onclick="window.open(this.href);return false;

 

[DaveEV]

So if the battery starts the day at 80°F (for example) and bakes all day when the ambient temperature rises to 90°F in the afternoon, then the battery probably won't get much over 85°F (just a guess on my part).

In my experience (using ELM327 to monitor temps), it seems that the battery follows ambient temps plus a few degrees pretty easily with the car sitting in the sun. It seems to take much longer to cool off. Parking in the shade will probably keep the car from exceeding daytime maximum temperature.

Not sure how much cracking the windows open when parked in the sun will help, but it certainly can't hurt.

 

[DaveinOlyWA]

It's pure SWAG based on anecdotes.

The "Stoaty" model is far better.

You can read about and download the Battery Aging Model ("Stoaty" model - developed by Surfingslovak, refined and fleshed out by Stoaty) here:

http://www.mynissanleaf.com/wiki/index.php?title=Battery_Capacity_Loss#Battery_Aging_Model" onclick="window.open(this.href);return false;

early results in but Steve Marsh first GID reading 231 @ 76,000 miles. to compare in Nov, 2012 he averaged 251 @ 56,000 miles so a loss of 6.8% in 20,000 miles which is higher than I was expecting. he mentioned he thought his loss accelerated when he started relying on QC more to make his commute.

There will be a change in the weather in the next few days which "should" boost his GID count slightly so a real comparison of degradation from Nov should be more accurate then even if the actual number is a bit misleading. will keep you posted

 

[Stoaty]

early results in but Steve Marsh first GID reading 231 @ 76,000 miles. to compare in Nov, 2012 he averaged 251 @ 56,000 miles so a loss of 6.8% in 20,000 miles which is higher than I was expecting. he mentioned he thought his loss accelerated when he started relying on QC more to make his commute.

With a bit more info I can see how the battery aging model prediction compares. Still need:

--months owned (to nearest half month)
--average miles per kwh
--how many days a week parked in the sun

 

[DaveinOlyWA]

early results in but Steve Marsh first GID reading 231 @ 76,000 miles. to compare in Nov, 2012 he averaged 251 @ 56,000 miles so a loss of 6.8% in 20,000 miles which is higher than I was expecting. he mentioned he thought his loss accelerated when he started relying on QC more to make his commute.

With a bit more info I can see how the battery aging model prediction compares. Still need:

--months owned (to nearest half month)
--average miles per kwh
--how many days a week parked in the sun

may 15th is his 2 year anniversary and his parking space at work is out in the open so 5 days a week all day but does have trees in the vicinity so "should" be partly shaded. keep in mind, he is on the shore of Puget Sound so it is significantly cooler than the surrounding area

averages low 4's for efficiency per dash
nov stats

https://docs.google.com/spreadsheet/ccc?key=0ArmkVCszTek9dC16a1Q4MjYxNHdJOWJva2s3NGViSnc&usp=sharing" onclick="window.open(this.href);return false;

I will ask him how he does in Summer for efficiency but guessing its the mid 4's as he probably does not drive as carefully because of the added range (I don't either. its cruise at 60-65 with A/C BLASTING away )

 

[TaylorSFGuy]

early results in but Steve Marsh first GID reading 231 @ 76,000 miles. to compare in Nov, 2012 he averaged 251 @ 56,000 miles so a loss of 6.8% in 20,000 miles which is higher than I was expecting. he mentioned he thought his loss accelerated when he started relying on QC more to make his commute.

With a bit more info I can see how the battery aging model prediction compares. Still need:

--months owned (to nearest half month)
--average miles per kwh
--how many days a week parked in the sun

24 months on Monday 13th
use 4.2 overall. Best run 63 miles freeway 4.8.
kept outside. In Seattle area. Your guess on days of sun that makes a difference. 15?

just leaving dealer. Dave beat me to it

 

[Stoaty]

may 15th is his 2 year anniversary and his parking space at work is out in the open so 5 days a week all day but does have trees in the vicinity so "should" be partly shaded. keep in mind, he is on the shore of Puget Sound so it is significantly cooler than the surrounding area

averages low 4's for efficiency per dash
nov stats

https://docs.google.com/spreadsheet/ccc?key=0ArmkVCszTek9dC16a1Q4MjYxNHdJOWJva2s3NGViSnc&usp=sharing" onclick="window.open(this.href);return false;

I will ask him how he does in Summer for efficiency but guessing its the mid 4's as he probably does not drive as carefully because of the added range (I don't either. its cruise at 60-65 with A/C BLASTING away )

Battery Aging Model Predicts 237 Gids given above info, so at 231 Gids he is 2.1% below what the model predicts. Still pretty close.

 

[QueenBee]

Battery Aging Model Predicts 237 Gids given above info, so at 231 Gids he is 2.1% below what the model predicts. Still pretty close.

Nice job on that model! From an outsider of such science and the model itself that seems dang accurate.

 

[DaveinOlyWA]

may 15th is his 2 year anniversary and his parking space at work is out in the open so 5 days a week all day but does have trees in the vicinity so "should" be partly shaded. keep in mind, he is on the shore of Puget Sound so it is significantly cooler than the surrounding area

averages low 4's for efficiency per dash
nov stats

https://docs.google.com/spreadsheet/ccc?key=0ArmkVCszTek9dC16a1Q4MjYxNHdJOWJva2s3NGViSnc&usp=sharing" onclick="window.open(this.href);return false;

I will ask him how he does in Summer for efficiency but guessing its the mid 4's as he probably does not drive as carefully because of the added range (I don't either. its cruise at 60-65 with A/C BLASTING away )

Battery Aging Model Predicts 237 Gids given above info, so at 231 Gids he is 2.1% below what the model predicts. Still pretty close.

throw in the fact that he does not park in the garage at home or work, could the extra solar loading (as little as it has been in the past but looks like will more than make up for that shortcoming this year) account for that 2.1%? Also, he may work on the shore but lives in Kent which is still close to the water but most of the area lies in the Kent Valley which means usually warmer than the surrounding areas. I am pretty sure he says he drives the LEAF very little on weekends, so it would be sitting out in the Sun most of the time

 

[user 11773]

I just had the battery tested again and the dealer is saying 11/12 bars. So, using the EPA mileage of 92 hwy, I should be able to get 91.7% of this or 84 miles? It shows 77 miles on the dash. I am going to my wife's office today; it is 64 miles roundtrip, at slower speeds than the limit, and run this thing until I get home and if it runs out, I will call for tow service paid for by Nissan. In another document, on this forum, it said 15% loss for first bar, so I should get 78 miles hwy. I turned off the warning indicators and also read the last bar has more power left than other bars and even on empty, there is a reserve. Any input?

 

[kolmstead]

Where'd you see an EPA range of 92 miles? I believe that the number was 73 for 2011-2012 Leafs. If you take off expecting 80+ miles from your 2011 Leaf, you're going to be stranded. If you really want to push to the limit, get one of the battery monitors available.... LeafDD, LeafSpy, or whatever. The fuel gauge on the dash is worse than useless. The bars mean whatever Nissan wants them to, and that changes as they tinker with the firmware.

-Karl

 

[DaveEV]

Any input?

11 capacity bars visible means you have between ~15-21% capacity loss. The first bar lost represents 15%, the rest represent an additional 6.25%. See wiki article: http://www.mynissanleaf.com/wiki/index.php?title=Battery_Capacity_Loss" onclick="window.open(this.href);return false;

EPA hwy range is more like 74 miles, not 92. Either way, YMMV, the Range Chart is a better estimate of actual range at various constant speeds.

Let's say you will be driving 64 miles today at 60 mph. The range chart says 82 miles until empty, but you are down around 18%, so that gives you 67 miles range (in 70F weather). Kansas is pretty damn cold today with temps around freezing. You can expect to lose at least another 10% range due to that (again, according to range chart), so now you're down to ~60 miles range.

Don't forget none of that accounts for HVAC draw, and you will very likely need to at least run the defroster a bit in those temps.

Personally, I wouldn't expect to get much more than 50 miles out of your car in those conditions. I estimate you'll have to drive no more than 55 mph to make it with minimal use of the HVAC.

 

[user 11773]

I am in San Luis Obispo, CA, Not sure where you got Kansas from. About 60 degrees, I got 92 miles from EPA data that was referenced in my sales brochure that said 100*. I am trying to make a point to NIssan, that they told us 100 and referenced EPA who said 92 hwy, and we will see what it actually is today.

 

[DaveEV]

I am in San Luis Obispo, CA, Not sure where you got Kansas from. About 60 degrees, I got 92 miles from EPA data that was referenced in my sales brochure that said 100*. I am trying to make a point to NIssan, that they told us 100 and referenced EPA who said 92 hwy, and we will see what it actually is today.

Hah, well, I read your user-name as LesKansas. Anyway, at 60F you have a chance of making it at 60 mph. Keep your mi/kWh over 4.0 and I think you can do it.

Still not sure were you are getting 92 miles - Nissan said 100 miles on the LA4 cycle, which is nothing like freeway/highway driving in terms of energy consumption.