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Or we just need better batt chemistries. Waiting for Li-Sulfur, Li-Air with double-triple density.

Then we need those batteries to be available for purchase to be applied into the Leafs by a new breed of electro auto mechanics. And then bye bye Nissan's dummy battery swap plan.

Future. It can't come fast enough.
 
tbleakne said:
I really wish Nissan would offer an active liquid cooling loop option. They could engineer the battery pack with the coolant channels in place, and these would be connected and filled with coolant if you bought the option.
It would be nice to be able to chill the pack to < 75F regardless of ambient temperature like cars with TMS do... In the mean time, you seem to be doing everything possible to keep your pack cool while keeping it garaged. I need to finish up the gable vent install in my garage to let in the cool night air. I might even add an exhaust fan to it to help move more air depending on how much airflow it helps generate. It's a 10F temp difference between the floor and ceiling when it warms up - I'm hoping convection is enough to bring the garage temps down.
 
The heat wave is having a substantial impact.
Late PM, Morning
Ambient. 95-100., 68-72
Garage. 82-85. , 72-75
Battery. 88-93. , 79-82

Very modest driving in afternoons raises battery temperature 10+ deg F.
Maintaining differential between garage and ambient is costing 4-10 kWh per day. Trying to keep the battery somewhat cooler by cooling the whole garage is very inefficient, but it still is an interesting experiment. In a few weeks I should be able to see whether this cooling is helping mitigate capacity loss at all or not.
 
tbleakne said:
The heat wave is having a substantial impact.
Late PM, Morning
Ambient. 95-100., 68-72
Garage. 82-85. , 72-75
Battery. 88-93. , 79-82

Very modest driving in afternoons raises battery temperature 10+ deg F.
Maintaining differential between garage and ambient is costing 4-10 kWh per day. Trying to keep the battery somewhat cooler by cooling the whole garage is very inefficient, but it still is an interesting experiment. In a few weeks I should be able to see whether this cooling is helping mitigate capacity loss at all or not.

Interesting stuff. Yesterday I completed a 200 mile trip. Used the DCQC for the first time. In fact, I visited 3 different DCQC stations, and one Level 2 station to make the 200 mile trip. Battery temps reached around 109F, and pretty much stayed there for a while. I can definitely confirm it takes forever to cool off! Driving through Woodland hills approached 110F ambient temps. Made sure I didn't stop to charge there! Too bad they did have a hose fitting, where you could just hook up your garden hose to cool off the pack when it is heat saturated. At 109F pack temp, the temp gauge read 7 bars. What are the battery temps others have approached? Is 7 bars, really typical, as far as it being far from the max readings on the temp gauge bars? When it was all said and done, I seemed to have lost over 1% capacity yesterday, even after the battery cooled off. There really seems to have been this downhill spiral with capacity. It usually goes down, and rarely goes up for any significant period of time. I was at 96% capacity just the other month. Now I am at 91%. Will post details of my trip, and all my battery readouts before and after each charge session, during my trek.
 
ELROY said:
tbleakne said:
The heat wave is having a substantial impact.
Late PM, Morning
Ambient. 95-100., 68-72
Garage. 82-85. , 72-75
Battery. 88-93. , 79-82

Very modest driving in afternoons raises battery temperature 10+ deg F.
Maintaining differential between garage and ambient is costing 4-10 kWh per day. Trying to keep the battery somewhat cooler by cooling the whole garage is very inefficient, but it still is an interesting experiment. In a few weeks I should be able to see whether this cooling is helping mitigate capacity loss at all or not.



Interesting stuff. Yesterday I completed a 200 mile trip. Used the DCQC for the first time. In fact, I visited 3 different DCQC stations, and one Level 2 station to make the 200 mile trip. Battery temps reached around 109F, and pretty much stayed there for a while. I can definitely confirm it takes forever to cool off! Driving through Woodland hills approached 110F ambient temps. Made sure I didn't stop to charge there! Too bad they did have a hose fitting, where you could just hook up your garden hose to cool off the pack when it is heat saturated. At 109F pack temp, the temp gauge read 7 bars. What are the battery temps others have approached? Is 7 bars, really typical, as far as it being far from the max readings on the temp gauge bars? When it was all said and done, I seemed to have lost over 1% capacity yesterday, even after the battery cooled off. There really seems to have been this downhill spiral with capacity. It usually goes down, and rarely goes up for any significant period of time. I was at 96% capacity just the other month. Now I am at 91%. Will post details of my trip, and all my battery readouts before and after each charge session, during my trek.

Was that 109F pack temp your highest sensor? Now I KNOW the 2013s' battery packs are a lot different! At 95.9F (highest sensor) triggers the 7th bar and 103.5F trips the 8th. When I had 9 TBs, the highest TS was 112F.
 
LEAFfan said:
ELROY said:
tbleakne said:
The heat wave is having a substantial impact.
Late PM, Morning
Ambient. 95-100., 68-72
Garage. 82-85. , 72-75
Battery. 88-93. , 79-82

Very modest driving in afternoons raises battery temperature 10+ deg F.
Maintaining differential between garage and ambient is costing 4-10 kWh per day. Trying to keep the battery somewhat cooler by cooling the whole garage is very inefficient, but it still is an interesting experiment. In a few weeks I should be able to see whether this cooling is helping mitigate capacity loss at all or not.



Interesting stuff. Yesterday I completed a 200 mile trip. Used the DCQC for the first time. In fact, I visited 3 different DCQC stations, and one Level 2 station to make the 200 mile trip. Battery temps reached around 109F, and pretty much stayed there for a while. I can definitely confirm it takes forever to cool off! Driving through Woodland hills approached 110F ambient temps. Made sure I didn't stop to charge there! Too bad they did have a hose fitting, where you could just hook up your garden hose to cool off the pack when it is heat saturated. At 109F pack temp, the temp gauge read 7 bars. What are the battery temps others have approached? Is 7 bars, really typical, as far as it being far from the max readings on the temp gauge bars? When it was all said and done, I seemed to have lost over 1% capacity yesterday, even after the battery cooled off. There really seems to have been this downhill spiral with capacity. It usually goes down, and rarely goes up for any significant period of time. I was at 96% capacity just the other month. Now I am at 91%. Will post details of my trip, and all my battery readouts before and after each charge session, during my trek.

Was that 109F pack temp your highest sensor? Now I KNOW the 2013s' battery packs are a lot different! At 95.9F (highest sensor) triggers the 7th bar and 103.5F trips the 8th. When I had 9 TBs, the highest TS was 112F.

I flirted with 37.0C (98.6F) yesterday on my max temp and never saw the 7th TB (2012 SL 94% health)
 
2013 SL delivered 3/15. ~7400 miles. Charged to 100%...sit 4 hours...charge to 100% Plug in ELM.....

Ahr=67.36
CAP= 101.67
SOC=96.7
23.4kWh
293 gids
 
That doesn't necessarily mean the packs are any different, just that they changed the temperature gauge or sensor calibration... Or that the data that is coming back from the 2013s is different and not indicating the temperature we think it is... The 2013 service manual should have the answer to gauge calibration...

LEAFfan said:
Was that 109F pack temp your highest sensor? Now I KNOW the 2013s' battery packs are a lot different! At 95.9F (highest sensor) triggers the 7th bar and 103.5F trips the 8th. When I had 9 TBs, the highest TS was 112F.
 
We got 2 Leafs a month ago:

2013 S (made May 2013) 1100 miles 60.79 AHr (never QC, mostly 80% L2)
2013 SV (made May 2013) 950 miles 60.31 AHr (Mostly 80% L2. A few QC, mostly to less than 80% to get home. )

Not very happy there has been so much loss. Perhaps we got a weak batch of batteries to start with.
 
So I was at Tustin Nissan and had a chance to check a few 2013s that came in to use the DCQC..
My 2013 rental 67.362Ah 110.48% H
Another 2013 65.02Ah 99.5% H
Another 2013 65.707Ah 100.58% H

I think 67.3620 is a cap on Ah capacity in the 2013s... Although I found an early screen shot of group 1 data from my first experiments with active sampling (late February?). The car (2012) was probably just a few weeks old. Health 0x28E9 (104.73%) and Ah capacity 0x0A4F60 (67.568Ah) !!!
Those were the days.. Last I checked (about 8800mi) it was already down to 61.808Ah 92.92%H
 
GregH said:
So I was at Tustin Nissan and had a chance to check a few 2013s that came in to use the DCQC..
My 2013 rental 67.362Ah 110.48% H
Another 2013 65.02Ah 99.5% H
Another 2013 65.707Ah 100.58% H

I think 67.3620 is a cap on Ah capacity in the 2013s... Although I found an early screen shot of group 1 data from my first experiments with active sampling (late February?). The car (2012) was probably just a few weeks old. Health 0x28E9 (104.73%) and Ah capacity 0x0A4F60 (67.568Ah) !!!
Those were the days.. Last I checked (about 8800mi) it was already down to 61.808Ah 92.92%H
Wow. I wish.
My brand new 2013 only reported 95% (63.10Ahr) the first time I checked. Now it's already down to 92% (61.50 Ahr) and it's a little over a month old.
How can there be such a wide range in new vehicle capacities. Ranging from 92-110%.
 
After one year and 9,600 miles:

57.22 AHr (86.36%)

Curiously enough, I'm already down to 11 bars. The only explanation I've been able to come up with is that I've seen a 100% charge end at only 91-92%. I'm thinking this must have to do with the battery's high temperature. It's hovering around 90F at this time of year.
 
Weatherman said:
After one year and 9,600 miles:

57.22 AHr (86.36%)

Curiously enough, I'm already down to 11 bars. The only explanation I've been able to come up with is that I've seen a 100% charge end at only 91-92%. I'm thinking this must have to do with the battery's high temperature. It's hovering around 90F at this time of year.
Wow.. is that the highest Ah capacity we've seen for an 11 bar car? I thought it was more like 54Ah to lose a bar...
Based on my experiences with both my 2011 and 2012 cars even sustained moderate heat (low 6 TBs.. 25-30C (77-86F)) can degrade the pack. Not cool (in more ways than one).
 
GregH said:
Based on my experiences with both my 2011 and 2012 cars even sustained moderate heat (low 6 TBs.. 25-30C (77-86F)) can degrade the pack. Not cool (in more ways than one).
Yes, indeed. The aging model Stoaty refined and several posters contributed to last year, predicted this outcome. That said, the model did not predict eight pack replacements under the new capacity in Phoenix after little more than two years of use :-(
 
I was thinking last night... what if I could, magically, snap my fingers and instantly transport my car to Eureka, CA and drive it there for a week? Would the 12th bar come back? Would the end point on a 100% charge be closer to 95%, than 90%?

We'll never know.

By the time temperatures cool off enough, down here (sometime in December), to allow the battery temp to drop into the lower 70s, it will have long since degraded below the typical 11 bar threshold.
 
What is AHr and how do you measure it ? I have a GID meter and that tells me the GID count aand the kWh. Is AHr a better parameter than kWh or GIDs ?

thanks
 
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