2016-2017 model year 30 kWh bar losers and capacity losses

[DaveinOlyWA]

Below was posted at http://www.mynissanleaf.com/viewtopic.p ... 04#p499004 on July 7, 2017:

2016 SV 7293 miles lost first bar, seems early to me based on other posts. 11/15 manufacture, 10/16 lease start for me, so do not know what the dealership did to the vehicle here in Orlando, FL between those two dates. Fortunately a leased car, so there is an end in sight.

I'm assuming this post at http://www.mynissanleaf.com/viewtopic.p ... 75#p499675 on July 16, 2017 from another thread is for the same vehicle.

Just lost my second bar as well, but at about 7,500 miles. 77% SOH

Ouch!

Would be interesting to know if his battery is defective and/or has bad cells.

2 bars lost in a few hundred miles?

This is an interesting case for sure.

[Oils4AsphaultOnly]

Just throwing some data out that I noticed today.

After 11k miles of 100% SOH, I lost 2% last night. I did keep my battery below 25% SOC these past few days and it seems to have affected the SOH reading. There have been a few days before where I left the car parked with an 87% SOC for the day and the SOH never went down. But after being under 22% last night (I park at 6pm, and the car doesn't start charging until 5am due to the charge timer) and I've dropped 2%.

Will charge to full in the next few days to see if the SOH recovers.

[Scaramanga]

I should like to point out that in January / February just after I took delivery of my '16 back in December (Happy Birthday to me!), my SOH% dropped to as low as 91% over a couple of months, I thought the whole thing was headed south, built a spreadsheet, got upset, etc.

I was only commuting 2 - 4 miles to work to the train station, and driving a bit on the weekends to Home Depot and such, still languishing in the 91 - 95% range.

Then my wife got a new job where I work in Bellevue and we've mixed up our commute to where sometimes I drive her and I all the way to Bellevue from Tacoma a couple times a month. About a 78 mile round trip on the freeway, in the HOV.

Lo and behold, my SOH% has returned to 100% and has stayed there for over a month consistently.

I don't know (okay I doubt) that the battery had just improved miraculously, it's likely just fat fingered instrumentation, but it's interesting from LeafSpy's point of view, the battery LIKES to be driven long distances where it starts at 100% full charge, get's driven at freeway speeds down to sub 20% and charged again on a timer the night before we take off again finishing at 100% within 20 minutes of departure.

Go figure, my spreadsheet has taken a u-turn and with less than 2k on the odometer things don't look so black.

[jbuntz]

Lost first bar briefly this morning. Stats are 61.83Ah 77% SOH 75.97 hx 9186 mi 283 GID 71.3 mi to LBW @ 3.9 m/kWh.

Been expecting it to go for a while, surprised it got this low before it dropped the first bar.

[jhm614]

Lost first bar briefly this morning. Stats are 61.83Ah 77% SOH 75.97 hx 9186 mi 283 GID 71.3 mi to LBW @ 3.9 m/kWh.

Been expecting it to go for a while, surprised it got this low before it dropped the first bar.

Ugh. Sorry for your loss. Did you buy new?

[jbuntz]

Lost first bar briefly this morning. Stats are 61.83Ah 77% SOH 75.97 hx 9186 mi 283 GID 71.3 mi to LBW @ 3.9 m/kWh.

Been expecting it to go for a while, surprised it got this low before it dropped the first bar.

Ugh. Sorry for your loss. Did you buy new?

New Dec 2016

[DaveinOlyWA]

I should like to point out that in January / February just after I took delivery of my '16 back in December (Happy Birthday to me!), my SOH% dropped to as low as 91% over a couple of months, I thought the whole thing was headed south, built a spreadsheet, got upset, etc.

I was only commuting 2 - 4 miles to work to the train station, and driving a bit on the weekends to Home Depot and such, still languishing in the 91 - 95% range.

Then my wife got a new job where I work in Bellevue and we've mixed up our commute to where sometimes I drive her and I all the way to Bellevue from Tacoma a couple times a month. About a 78 mile round trip on the freeway, in the HOV.

Lo and behold, my SOH% has returned to 100% and has stayed there for over a month consistently.

I don't know (okay I doubt) that the battery had just improved miraculously, it's likely just fat fingered instrumentation, but it's interesting from LeafSpy's point of view, the battery LIKES to be driven long distances where it starts at 100% full charge, get's driven at freeway speeds down to sub 20% and charged again on a timer the night before we take off again finishing at 100% within 20 minutes of departure.

Go figure, my spreadsheet has taken a u-turn and with less than 2k on the odometer things don't look so black.

As you well know, this is quite normal. The real question is do the higher numbers mean higher range? I have not found any evidence to the contrary as of yet. So wondering how those 200,000 mile Tesla's did it? Its because they were driven!

So why did the numbers improve? Well, part of the reason is your cells are better matched to each other. Cells balance ALL the time but if not full, there is nothing stopping top cells from continuing to take a charge and the balancing charge is very weak. But as cells approach the max voltage cut off, they stop taking a charge allowing lower cells to catch up much more effectively.

So short drives means shorter charging time and in most cases, less time for lower cells to balance with the higher cells. Longer drives means longer charging time, longer balancing time.

There is undoubtedly other forces at work here, but the results are very repeatable which I have reported on several times in my blog. Right now, I am at 100% after 19,000 miles and UNDOUBTEDLY because I am averaging 80+ miles per day

[DaveinOlyWA]

Lost first bar briefly this morning. Stats are 61.83Ah 77% SOH 75.97 hx 9186 mi 283 GID 71.3 mi to LBW @ 3.9 m/kWh.

Been expecting it to go for a while, surprised it got this low before it dropped the first bar.

Ugh. Sorry for your loss. Did you buy new?

New Dec 2016

A year on the lot... not surprised. We need to add build date to profile. Its a too reoccurring issue sadly

[SageBrush]

I should like to point out that in January / February just after I took delivery of my '16 back in December (Happy Birthday to me!), my SOH% dropped to as low as 91% over a couple of months, I thought the whole thing was headed south, built a spreadsheet, got upset, etc.

I was only commuting 2 - 4 miles to work to the train station, and driving a bit on the weekends to Home Depot and such, still languishing in the 91 - 95% range.

Then my wife got a new job where I work in Bellevue and we've mixed up our commute to where sometimes I drive her and I all the way to Bellevue from Tacoma a couple times a month. About a 78 mile round trip on the freeway, in the HOV.

Lo and behold, my SOH% has returned to 100% and has stayed there for over a month consistently.

I don't know (okay I doubt) that the battery had just improved miraculously, it's likely just fat fingered instrumentation, but it's interesting from LeafSpy's point of view, the battery LIKES to be driven long distances where it starts at 100% full charge, get's driven at freeway speeds down to sub 20% and charged again on a timer the night before we take off again finishing at 100% within 20 minutes of departure.

Go figure, my spreadsheet has taken a u-turn and with less than 2k on the odometer things don't look so black.

Very interesting -- thanks.
I've also noticed a 10% drop in estimated capacity, SOH and history during the six months we have owned and babied the car, and mostly used it for 3 mile drives ... yet the range has stayed about the same. I'm inclined to think that measuring artefacts are in play here too, so I'm trying to not extrapolate a poor future.

[DaveinOlyWA]

I should like to point out that in January / February just after I took delivery of my '16 back in December (Happy Birthday to me!), my SOH% dropped to as low as 91% over a couple of months, I thought the whole thing was headed south, built a spreadsheet, got upset, etc.

I was only commuting 2 - 4 miles to work to the train station, and driving a bit on the weekends to Home Depot and such, still languishing in the 91 - 95% range.

Then my wife got a new job where I work in Bellevue and we've mixed up our commute to where sometimes I drive her and I all the way to Bellevue from Tacoma a couple times a month. About a 78 mile round trip on the freeway, in the HOV.

Lo and behold, my SOH% has returned to 100% and has stayed there for over a month consistently.

I don't know (okay I doubt) that the battery had just improved miraculously, it's likely just fat fingered instrumentation, but it's interesting from LeafSpy's point of view, the battery LIKES to be driven long distances where it starts at 100% full charge, get's driven at freeway speeds down to sub 20% and charged again on a timer the night before we take off again finishing at 100% within 20 minutes of departure.

Go figure, my spreadsheet has taken a u-turn and with less than 2k on the odometer things don't look so black.

Very interesting -- thanks.
I've also noticed a 10% drop in estimated capacity, SOH and history during the six months we have owned and babied the car, and mostly used it for 3 mile drives ... yet the range has stayed about the same. I'm inclined to think that measuring artefacts are in play here too, so I'm trying to not extrapolate a poor future.

It does lend some credence to "stretching the LEAF legs" every once in a while where you take a drive, run it down to 20% then do a full overnight charge.

Not sure if its wise but taking another route might be looking at increasing the balancing current but there is likely a risk from increased heat and loss that might not be in our best interests.