The 40KWH Battery Topic

I get why people who do not have LeafSpy look at capacity bars, or look at bars when warranty questions arise; but along the way SOH (or my favorite, drop in Ahr) is really all a LEAF owner should care about.

So 15% drop in capacity in ~ 4 years.

That is really piss poor since it translates into a LEAF getting relegated to errand status in about 8 years from new for the lion's share of car owners. I've always been sensitive to this issue due to car value, but now that I finally convinced my wife that we should be a one car family I think about it even more since we cannot amortize a rapidly degrading EV as part of a 1.5 cars household.

I'm too busy these days to spend anywhere near as much time on car forums as in the past, but the Tesla, Bolt and this LEAF forums are such remarkable microscopes into each car's fault lines:

Tesla: price and autopilot
Bolt: GM, car size, and DC charging
LEAF: Battery degradation and DC charging

knightmb said:

My wife finally managed to torture her Leaf into losing a bar, though it still shows all of them for some reason. Either that or my memory is bad, I thought the first bar dropped after 85% SoH? Yes, her dash is that dirty. I thought mine was bad. :lol:

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You have bad memory but mine is hardly good but I don't remember a single car that dropped at 85%. I do have a list that shows most dropping between 84½ and 83¾%

There are only two in my world who lost a bar on a Gen 2 who had fairly recent LS stats and both were in the mid to low 83's.

DaveinOlyWA said:

There are only two in my world who lost a bar on a Gen 2 who had fairly recent LS stats and both were in the mid to low 83's.

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That tracks nicely with Gen1 losing bar #1 when down 16.5% of capacity. That tidbit suggests that Nissan has not mucked around with the threshold for loss of bar #1

If things are the same as Gen1, then bar #1 and bar #12 are 16.5% each, and the remaining 10 bars are 6.7% each.

Parenthetically, I'm always amused by people who wear the 12th bar as a badge of honor, not realizing that up to ~ 16% of new pack capacity may have already been lost.

DaveinOlyWA said:

You have bad memory but mine is hardly good but I don't remember a single car that dropped at 85%. I do have a list that shows most dropping between 84½ and 83¾%

There are only two in my world who lost a bar on a Gen 2 who had fairly recent LS stats and both were in the mid to low 83's.

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So at 84.29%, she should have dropped a bar then? That is what she has currently.

It's nowhere near that precise a process. It should drop it before it hits 83.0%.

LeftieBiker said:

It's nowhere near that precise a process. It should drop it before it hits 83.0%.

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Oh, didn't know that, thanks for the update!

People waiting to lose 4 bars for a warranty replacement have gotten very frustrated, waiting for the 4th bar to drop after the SOH reaches the minimum. Then there is the occasional bar that drops...and then comes back for a while, sometimes more than once. Like the cinematic watched clock that backs up a second while you're staring at it.

knightmb said:

DaveinOlyWA said:

You have bad memory but mine is hardly good but I don't remember a single car that dropped at 85%. I do have a list that shows most dropping between 84½ and 83¾%

There are only two in my world who lost a bar on a Gen 2 who had fairly recent LS stats and both were in the mid to low 83's.

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So at 84.29%, she should have dropped a bar then? That is what she has currently.

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No. Only in the neighborhood. The bars NEVER represented lines in the sand. I think they drop based on several parameters beyond ahr/SOH including measurements we can't effectively track like resistance or things we can loosely observe like cell balance. As you have probably guessed, resting cell balance is like a coffee table book; for looks only.

But loaded cell balance is something LEAF Spy is not really equipped to show w/o pouring thru the data logs and even then I wonder whether all the measurements are all done at once?

But its appearing that the Gen 2's are dropping a bit lower, maybe ¼ to ½% lower but my guess is that the bars still loosely represent 15% on the top but the reserve is not considered so you are losing the 15% plus the reserve which is likely not only bigger but adjustable which may account for the positive adjustments we see.

There is one LEAFer who hasn't reported in this cycle but he was in the mid 83's and had been for 6+ months and he was my prediction to drop a bar first but it has hung on. He did get a small bump up, likely less than .2% so that gave him extra time.

Some high ish mile 40kWh Leafs and their battery states.

https://medium.com/@eTaxidriver/an%C3%A1lisis-de-las-bater%C3%ADas-del-nissan-leaf-40-kwh-despu%C3%A9s-de-4-a%C3%B1os-22755716ae7c

Pretty definite that the 40 is better than 30.

DougWantsALeaf said:

Some high ish mile 40kWh Leafs and their battery states.

https://medium.com/@eTaxidriver/an%C3%A1lisis-de-las-bater%C3%ADas-del-nissan-leaf-40-kwh-despu%C3%A9s-de-4-a%C3%B1os-22755716ae7c

Pretty definite that the 40 is better than 30.

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Several "coincidences" to note; There are only 3 in the group that didn't charge regularly to full and their SOH rank?

Thinking a few might be able to guess that

Thanks Doug! I had to use Google Chrome's translate to be able to understand the page. https://translate.google.com/ didn't work for me w/that URL.

What Dave mentioned is no surprise.

Given these are worst case scenario Leafs in terms of use, I think it bodes well for the non commercial Leaf owners.

2018 MY SL
Put into service 2019 MAY
Central NC US
28,300 miles
267 qc 647 l1 l2
SOH 89

SOH first two years dropped by around 3.5 pct per year then appears to slowed to around 1.5 pct in 3rd yr to about 1 pct in current year


Thoughts?

61K miles and & other than losing 11.5% capacity I'm fairly impressed with the battery capacity degradation so far! My biggest disappointment is how much regen capacity I have lost. When the car was new I had all blue regen bars around 90-92% IIRC and now that doesn't happen until I am down to 72-74% depending on pack temp so that's by far the most noticeable 'loss' I have experienced and makes me wonder how much further that will degrade because that's been an ongoing gradual loss of 'performance'

Also interesting to note that the car was 'fully' charged with no blinking dash but LeafSpyPro is reporting 97.2% SOC...

Herding, what are your charging habits?

I looked at a 2018 leaf sl with no blinking dash, not sure why, any comments?

rogersleaf said:

rogersleaf said:

rogersleaf said:

Reached the 3-year anniversary and 60,000 miles.

LS stats:
AHr... 103.21
SOH... 89.41%
Hx... 104.43%
SOC... 98.4% and 449 GID
409.90v, cells balanced between 4.195-4.199v
odo... 60,226
41 QC / 1477 L2’s

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Past 65,000 miles.
Nothing spectacular happening...

LS stats:
AHr... 102.97
SOH... 89.20%
Hx... 95.94%
SOC... 96.9% and 441 GID
402.47v, cells balanced between 4.191-4.194v
odo... 65,114
43 QC / 1626 L2’s

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70,000 mile figures:

LS stats:
AHr... 100.87
SOH... 87.38%
Hx... 88.86%
SOC... 96.7% and 431 GID
403.54v cells balanced between 4..202 and 4.205v
odo... 70,687
43 QC / 1771 L2’s

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Now passing 76,000 miles. Car & battery seems to be stable and working fine. Likely just intuition, but sense the battery capacity is more sensitive to the cold than prior Winters. Thus far it hasn't affected the car's utility for my needs but noticing the usable range is dropping off much faster on those colder days. It's definitely not being left outside this Winter.

LS stats:
AHr... 100.93
SOH... 87.47%
Hx... 91.42%
SOC... 96.2% and 429 GID
402.06v cells balanced between 4.186 and 4.190v
odo... 76,078
45 QC / 1937 L2’s

DougWantsALeaf said:

Herding, what are your charging habits?

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Hey Doug, I missed the notification on your question so sorry about the delayed reply.

Typically try to keep the car between 30-70% although in colder weather I am charging closer to to 80-85% for extra cushion & being down 11% capacity although that limits full regen until I get down to 70-72% SOC nowadays.

I do a full 100% balancing charge every 1-2 months typically but try to do that when I head to a town 30 miles south so I don't stay at 100% for any length of time.

Also last summer I started using a 230V 10A charger so I'm putting less heat in the pack because we saw as high as 117F last summer and multiple 113F days. Zip code 93446 for reference. In this scenario I commence charging around midnight & charge for 4-8 hours depending on SOC when I pull into the garage each night. It really keeps the pack temps from creeping from the charge session as well.

And I use the OEM 6.6kW charge for winter use & try to conclude charging with 1-2 hours of leaving to pre warm the pack for better winter performance.

https://www.facebook.com/groups/NissanLeafOwners/posts/6171238312974106/ in Japan is at 258,624 km (about 160.7K miles). SOH is at 80.65%. They're down a capacity bar and confirmed in a reply w/a pic of their capacity bar display.

HerdingElectrons said:

Also last summer I started using a 230V 10A charger so I'm putting less heat in the pack because we saw as high as 117F last summer and multiple 113F days. Zip code 93446 for reference. In this scenario I commence charging around midnight & charge for 4-8 hours depending on SOC when I pull into the garage each night. It really keeps the pack temps from creeping from the charge session as well.

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These are good charging habits for warm climates (which I live in).
I have kept my original Nissan EVSE (modified for 220v) for the very purpose of "slow" 220v charging (16a). I also typically charge late at night--or at least after the pack has cooled from normal driving/use.
A big (hidden) benefit of the larger battery packs (e.g. not 24 kWh) is that you don't have to keep the SOC high for useful range.