The 40KWH Battery Topic

My Latest Data:

Date SOH AMPHr Hx
5/3/2019 97.63 112.7 97.5
5/6/2019 97.62 112.69 97.94
5/7/2019 97.61 112.68 98.03
5/10/2019 97.6 112.67 98.39
5/13/2019 97.59 112.66 98.55
5/15/2019 97.58 112.65 98.73
5/19/2019 97.57 112.63 98.84
5/27/2019 97.55 112.61 99.27
6/1/2019 97.53 112.59 99.61
6/4/2019 97.5 112.55 100.12
6/11/2019 97.44 112.48 101.03
6/12/2019 97.43 112.47 101.25
6/13/2019 97.42 112.46 101.25
6/14/2019 96.49 111.39 101.58
6/15/2019 96.28 111.15 101.58
6/16/2019 95.64 110.41 101.67
6/17/2019 95.42 110.15 101.82
6/19/2019 95.4 110.13 102.15
6/20/2019 95.38 110.11 102.25
7/15/2019 95.19 109.89 103.22
7/24/2019 95.1 109.78 104.04
8/11/2019 94.9 109.55 104.95

rogersleaf said:

Mine passed the 5000 mile mark yesterday, 10 weeks of ownership.

LS stats:
AHr... 113.65
SOH... 98.45%
Hx... 115.83%
SOC... 99.2% and 498 GID
403.61v, cells balanced between 4.202-4.206v
odo... 5009
5 QC / 147 L2’s

Should add that L2’s are typically done overnight with charge timers set to not fully charge before I leave in the morning. The car rarely sits on full charge and have yet to reach LBW.

Click to expand...

Reached 10,000 miles at 1 week short of 5 month ownership.

LS stats:
AHr... 111.16
SOH... 96.29%
Hx... 115.17%
SOC... 98.8% and 486 GID
403.75v, cells balanced between 4.202-4.206v
odo... 10002
7 QC / 269 L2’s

2018 Leaf SV leased in March of 2019. 7000 miles on odometer. Build date February 2018.

Date AHr TemperatureF
3/15/19 112.52 69.1
4/15/19 112.45 75.2
5/15/19 112.37 82.2
6/15/19 110.11 90.8
7/15/19 109.64 97.0
8/15/19 109.24 101.8

This might be a dumb question but has anyone actually done some experiments to verify the range is actually dropping with these digital stats?

IN Theory I've lost 3% of my capacity but I haven't noticed any drop in the car's estimated range. Admittedly 3% would be hard to detect so I'm wondering if anyone did / has done an actual experiment? I'm just wondering because the data is so artificial in nature - dropping .01 every day witch bigger drops every 3 months or so. I'm just curious if anyone has verified through actual usage?

Of course the problem with that is finding a repeatable drive - I certainly couldn't do it. With changes in temp and wind where I live, I'd never be able to see a drop in range of probably less than 10%. But some type of experiment where you drive 50 miles, same conditions, and see how much of the battery it uses. I would expect it to use more as the SOH decreases.

I guess I'm just wondering if on 2018's and 2019's anyone has connected these "stats" to the real world.

danrjones said:

This might be a dumb question but has anyone actually done some experiments to verify the range is actually dropping with these digital stats?

IN Theory I've lost 3% of my capacity but I haven't noticed any drop in the car's estimated range. Admittedly 3% would be hard to detect so I'm wondering if anyone did / has done an actual experiment? I'm just wondering because the data is so artificial in nature - dropping .01 every day witch bigger drops every 3 months or so. I'm just curious if anyone has verified through actual usage?

Click to expand...

Interesting you make this observation, my own is similar. The stats don't seem to track with real world range loss. Sometimes even think the loss curve behaves more like an absolute value rather than a relative value percentage of the battery size like the 24KWh LEAF. To me, range loss thus far feels so insignificant it's not noticeable... then again, ask me this in January when it's -5F and need all the capacity possible to get home from work.

We at this site found that with the 24kwh pack that the first 5% or so of capacity loss wasn't usually noticed. My theory on that is that the driver is learning to drive more efficiently at the same rate as the loss, so until it approaches 10% or so it isn't noticed as range loss. My 40kwh GOM is showing slightly lower numbers than when the car was new, but I use so little of the capacity that I won't notice actual range loss for a long time, if ever. Our 2013 PIP, OTOH, has lost about a third of its original EV capacity, and that has become noticeable.

That would support the Theory that Tesla drivers (early ones) claimed to have almost no range loss, and only started to complain when this losses became sizable (as in last software update). As most drivers were using much less than their range, the small losses were not noticeable. When you need 85 of your original 84 miles of range, every mile hurts.

All that said, the first leaf owner to hit 100k miles (I think in late 2013..maybe 2014) still had 12 bars at 100k miles. My experience is time more than use drives the degradation. It’s why I want to get all my road trips in this year in the plus.

I agree with the balance of first 5% with driver efficiency. Also your tires get a little more efficient during first 10k miles as they get smoother.

I agree with the balance of first 5% with driver efficiency. Also your tires get a little more efficient during first 10k miles as they get smoother.

Click to expand...

Also drivetrain bearings wearing in and loosening a little.

danrjones said:

This might be a dumb question but has anyone actually done some experiments to verify the range is actually dropping with these digital stats?

IN Theory I've lost 3% of my capacity but I haven't noticed any drop in the car's estimated range. Admittedly 3% would be hard to detect so I'm wondering if anyone did / has done an actual experiment? I'm just wondering because the data is so artificial in nature - dropping .01 every day witch bigger drops every 3 months or so. I'm just curious if anyone has verified through actual usage?

Of course the problem with that is finding a repeatable drive - I certainly couldn't do it. With changes in temp and wind where I live, I'd never be able to see a drop in range of probably less than 10%. But some type of experiment where you drive 50 miles, same conditions, and see how much of the battery it uses. I would expect it to use more as the SOH decreases.

I guess I'm just wondering if on 2018's and 2019's anyone has connected these "stats" to the real world.

Click to expand...

On paper, I have lost 7% and TBH, don't know what my new range was. I did 181 miles once but that included 60 miles of 35-40 mph driving around town stuff. Friday, I went to the Dungeness Spit to hike it to the lighthouse and back (its one of the longest spits in the World) 5.71 miles EACH way with my Son (he hates me now ...)

But I drove from Lacey to Port Angeles to charge; 128.3 miles driving 50-70 mph (most of it at 65 mph) averaging a very pedestrian 4.8 miles/kwh and still had 40 miles of range left. So I "maybe" have lost "some" but I would not quantify it as 7%

I should add, my 181 mile jaunt averaged in the mid 5's.

danrjones said:

This might be a dumb question but has anyone actually done some experiments to verify the range is actually dropping with these digital stats?

Click to expand...

My 24kWh Leaf did start to show some noticeable range loss when I got below 85 - 90% SOH. I could tell that because I had a 55 mile round trip commute so I was charging to 100% each night and hitting LBW every day in the winter. Whether or not it was 15% is hard to say because there are so many variables like heat use, ambient temperature, wind, and traffic... but the loss was definitely there. It was like a climate record, I started recording a lot more low end values and a lot fewer high end values in terms of my SOC level when I got home from work.

The 40kWh Leaf has too much range for me to notice any losses. I rarely go above 90% or below 20% SOC now, even if I have to cart my kid to some after school activity, so there is just no way for me to tell what my actual range is. I honestly don't know if I've even hit the LBW on this car yet come to think of it (after 7000 miles of driving).

I suppose if I was really curious I could consistently record temperature and set the cruise control at a fixed value while leaving the cabin heat off. With a very standard work commute, a bunch of data points would beat down the noise and converge on a realistic range. Then I could do the same thing next year, and the next, and the next to establish a trend... honestly I don't care enough to do that though I just want to drive my car to work and take care of whatever errands I need to do.

I'm the same way, I don't drive enough to notice losses if they are real. In fact I tend to charge about every other night for 2 hrs only on lvl 2. That's all I need. I get down to about 50% and charge back to about 80%.

Though twice a year I'll need to drive a round trip of about 180 miles to get it "serviced". With the chargers popping up it really shouldn't be an issue,

Same with us with our 2016 SV. No noticeable range loss. Every couple weeks we have a road trip so we do a full overnight L2. GOM still usually around 204 km.

I wonder if you could build in a small algorithm which undershoots efficiency to start, then slowly ramps it up over a few years (and maybe shrinking a reserve). This would give you the feeling of a stable usable range, and manage the battery decline for say 3 years, which would give people a good feeling. Then a gentle decline would be considered acceptable as the car would no longer be "new". It would also manage through most lease agreements.

I follow some of the Tesla boards, and the amount of screaming after the software change has been deafening (and as they are well healed lawsuits are following). Also, there are a growing number of Bolt drivers reporting 10% range drops and more after 2-3 years of driving. While I would put both at rates less than what most (now not all) leaf drivers experience, its not 0. Maybe 3% a year across it all. Our 13 leaf, which was at the center of the curve, lost about 20% after 6 years, 11 of 12 bars, but we only put on 6K miles a year (traded it in at 37K miles).

My 2018 has in theory lost almost 6% but the first 3% was before I bought it, as it sat around for a full year on a hot dealer lot.

But the second part of that is how that loss curve changes over time - will it be linear? Will it level off over time?

Assuming the loss is real, I could see 8% by the end of my first year (two years including the time on the lot)
But the next two years after that could be 4%.

https://www.independent.co.uk/life-style/electric-car-volkswagen-e-golf-london-cornwall-drive-a9056226.html

Looks like the eGolf has similar GOM dynamics to the Leaf. Maybe a bit worse.

I still advocate for a kWh remaining on the dash. Its like gallons remaining in the tank. Based on weather, speed, etc. you can you use your super computer on your shoulder to determine remaining range.

I still advocate for a kWh remaining on the dash. Its like gallons remaining in the tank. Based on weather, speed, etc. you can you use your super computer on your shoulder to determine remaining range.

Click to expand...

How would that be different from a SOC display? If I see kwh remaining, I will convert to fractions of full/SOC% in my (formerly) supercomputer.

DougWantsALeaf said:

I follow some of the Tesla boards, and the amount of screaming after the software change has been deafening

Click to expand...

Err .... what are you talking about ?

danrjones said:

My 2018 has in theory lost almost 6% but the first 3% was before I bought it, as it sat around for a full year on a hot dealer lot.

But the second part of that is how that loss curve changes over time - will it be linear? Will it level off over time?

Assuming the loss is real, I could see 8% by the end of my first year (two years including the time on the lot)
But the next two years after that could be 4%.

Click to expand...

If it were linear in time or distance, I would be over 10% by now. As reported, I get large adjustments to the BMS every 90 days which have all gone down except the last one which went up. If the next one goes down, that essentially means 6 months of negated changes with a net result near zero.

Latest Data

Date SOH AMPHr Hx
5/03/2019 97.63 112.70 97.50
5/06/2019 97.62 112.69 97.94
5/07/2019 97.61 112.68 98.03
5/10/2019 97.60 112.67 98.39
5/13/2019 97.59 112.66 98.55
5/15/2019 97.58 112.65 98.73
5/19/2019 97.57 112.63 98.84
5/27/2019 97.55 112.61 99.27
6/01/2019 97.53 112.59 99.61
6/04/2019 97.50 112.55 100.12
6/11/2019 97.44 112.48 101.03
6/12/2019 97.43 112.47 101.25
6/13/2019 97.42 112.46 101.25
6/14/2019 96.49 111.39 101.58
6/15/2019 96.28 111.15 101.58
6/16/2019 95.64 110.41 101.67
6/17/2019 95.42 110.15 101.82
6/19/2019 95.40 110.13 102.15
6/20/2019 95.38 110.11 102.25
7/15/2019 95.19 109.89 103.22
7/24/2019 95.10 109.78 104.04
8/11/2019 94.90 109.55 104.95
8/30/2019 94.73 109.36 106.05
9/05/2019 94.68 109.30 106.27

Where are the temp sensors on the battery?

Last night I went to bed the temps were 97.7 max and 96.2 min, not a big spread.

This am the temps were 87.4 and 80.6. Pretty big spread?