Capacity Loss on 2011-2012 LEAFs

[mwalsh]

Any updates on the 5-6 people who in may listed their Leafs with full capacity. It would be nice to note if and when they lose a bar.

I've still got all my bars. SOC (as measured on the Gidometer) is down from high 80s/low 90s in May/June/July to low to high 80s in August and this month. Though I am rather hoping for a bit of a bounce back with cooler weather. I may, emphasize, may have seen stabilization in SOC losses, in that I haven't broken below 80% yet (except for an anomalous 70-something reading in June).

 

[mark1313]

Just from the education that Im getting on the Leaf here in trying to extend the battery life,I went from driving slow to slower(6.1MKW)No AC most of the summer,I still saw 7 temp bars tho,tried to cool the very hot garage a few degrees..So just maybe the 3rd bar will show up later

1. Azdre & Opossum - April 26, 2012. 16.6K miles/13 months ownership. Phoenix (2nd bar loss reported 6/14/2012 @~19K miles) (8/2/2012)
2. bturner - May 12, 2012. 13.6K/12 months. Phoenix (2nd bar loss reported 7/7/2012) (9/1/2012)
3. turbo2ltr - May 18, 2012. 13K/15 months. Phoenix (2nd bar loss reported 6/29/2012) (8/10/2012)
6. Mark13 - May 22, 2012. 15.7K/12 months. Phoenix (2nd bar loss reported 7/1/2012) (8/10/2012)
23. jhm614 - May 15, 2012, 25K/14.5 months, Arlington, TX (2nd bar loss reported on 7/7/2012) (8/29/2012)

I have added a date in red which shows when these cars would lose their third bar assuming it takes exactly the same number of days it took to lose the second one. Of course no one knows if these cars will lose their third bar before, on, or after these dates and there are many factors which will affect that, including the temperatures in Phoenix and Arlington, but I wanted to make some markers that we could track.

Just a quick follow-up on this post. Three of these dates are now in the past and none of those three made it onto the 3-bar loss list yet. So for this small sample, it does not seem like accelerating or even constant loss rate.

We're getting a lot of data recently and Stoaty has done a great job with plotting it, so we should start seeing clear trends in how this loss progresses.

Thanks to Stoaty and Vicki and everyone else for maintaining the data in Wiki!

 

[smkettner]

99 degrees today, and the first day at 7 bars on the temp scale for the year. Supposed to be even hotter tomorrow, but I've nowhere I really need to be, so I'll let the LEAF rest up.

Supposed to cool off to 70 tonight, are you parking outside?
Two days ago I installed a fan to get cool air into my garage from 11p to 6a.
I did not see the dreaded 7th bar today but it must be close.

 

[JPVLeaf]

99 degrees today, and the first day at 7 bars on the temp scale for the year. Supposed to be even hotter tomorrow, but I've nowhere I really need to be, so I'll let the LEAF rest up.

I've still got all my bars. SOC (as measured on the Gidometer) is down from high 80s/low 90s in May/June/July to low to high 80s in August and this month. Though I am rather hoping for a bit of a bounce back with cooler weather. I may, emphasize, may have seen stabilization in SOC losses, in that I haven't broken below 80% yet (except for an anomalous 70-something reading in June).

M, my gids seem to have been tracking similar to yours at 100% (-2/+6) since May '12. Except, my weekday temps are on avg. 10°F more than yours (108°F today), you have 6 mos on me, but I have 2k mi. on you. In an attempt to compensate for the weekday higher inland temps, I started experimenting with a weekday charging routine which I can only speculate has accounted for holding up my gids up by a few compared to the alternative. I hit 7 temp bars just the 3rd time this summer, I like to think thanks to this routine. I would've expected to see 7 at least twice as often otherwise considering the number of 100°F days this summer in DB (16+ in August).

Looking forward to cooler temps for many reasons, not the least of which to see if/how much of a gid rebound there is. Can't come soon enough.

 

[vrwl]

M, my gids seem to have been tracking similar to yours at 100% (-2/+6) since May '12. Except, my weekday temps are on avg. 10°F more than yours (108°F today), you have 6 mos on me, but I have 2k mi. on you. In an attempt to compensate for the weekday higher inland temps, I started experimenting with a weekday charging routine which I can only speculate has accounted for holding up my gids up by a few compared to the alternative. I hit 7 temp bars just the 3rd time this summer, I like to think thanks to this routine. I would've expected to see 7 at least twice as often otherwise considering the number of 100°F days this summer in DB (16+ in August).

Looking forward to cooler temps for many reasons, not the least of which to see if/how much of a gid rebound there is. Can't come soon enough.

So what's the weekday charging routine you're experimenting with?

 

[edatoakrun]

Looks like the rate of bar losses as reported on the wiki may be slowing, but there have been lulls previously, only to have the rate pick up again.

By my count, six losses of the first bar, and one second bar loss reported (so far) since 9/1.

This compares with ~18 with dates confirmed (and ~4 others with unconfirmed dates) reported over the last 2 weeks of August, and ~24 reported for the first two weeks of August.

Five of of the September seven are from SOCAL.

Been warm down there, over the last few weeks?

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

 

[DaveinOlyWA]

99 degrees today, and the first day at 7 bars on the temp scale for the year. Supposed to be even hotter tomorrow, but I've nowhere I really need to be, so I'll let the LEAF rest up.

Supposed to cool off to 70 tonight, are you parking outside?
Two days ago I installed a fan to get cool air into my garage from 11p to 6a.
I did not see the dreaded 7th bar today but it must be close.

a cool night will yield no results. wait another 3-4 weeks. you must have 2-3 days of cooler weather for it to make a difference i am guessing. and it appears that one warmer day does not affect that much.

we had temps in upper 60's low 70's for about 10 days but one day in mid 80's. previous to that it was warm for us averaging low to mid 80's and i was getting consistent GID readings from 268 to 272 including 5 days in a row where measurements ranged from 270-272 so pretty consistent.

so i figured, "ok, i have 4% loss" since it was 270 3 of those times. then i randomly charged to 100% every few days getting same results. then the weather broke, we had several mornings in the mid to upper 40's. i charged once and got 272 so thinking "ok, close enough to my 270 i call it good". went anther 4 days, charged again and got 275 yesterday and 277 this morning.

garage temp 62º OAT 52º. i have not seen 277 since July (obtw, our warm summer did not start until last week of July and it wasnt very warm either. around here, i consider anything over 75 to be warm)

so, now; after being convinced i knew what i knew and after 19 months and 21,500 miles, it all made perfect sense as well...now i am faced with

**have i only lost temporary capacity? and full charge capacity will come back just in time for cold weather limitations? which i am already comfortable with (actually much much more comfortable with this year now that QC is sitting 2 miles away from longest commute destination?)

** if i am seeing a 3-6% degradation in my relatively mild weather conditions ( Southern CA ALERT i did get readings in the 263 range which i think you will find recognizable when i charged during daylight and temps in the mid 90's which a lot of you would see. it took 4 days for the SOC to get that low despite the 3rd day being the hottest) then to what degree would Phoenix drivers and see and would they ever see a 100% again?

i originally thought AZ owners might see a 7% return on SOC when the weather cools off but now i am thinking it might be more as in nearly double that. i am a bit shocked at how sensitive the battery is to temps and that the optimum point seems to be more in the low 60's range than i previously thought

 

[edatoakrun]

99 degrees today, and the first day at 7 bars on the temp scale for the year. Supposed to be even hotter tomorrow, but I've nowhere I really need to be, so I'll let the LEAF rest up.

Supposed to cool off to 70 tonight, are you parking outside?
Two days ago I installed a fan to get cool air into my garage from 11p to 6a.
I did not see the dreaded 7th bar today but it must be close.

a cool night will yield no results. wait another 3-4 weeks. you must have 2-3 days of cooler weather for it to make a difference i am guessing. and it appears that one warmer day does not affect that much.

we had temps in upper 60's low 70's for about 10 days but one day in mid 80's. previous to that it was warm for us averaging low to mid 80's and i was getting consistent GID readings from 268 to 272 including 5 days in a row where measurements ranged from 270-272 so pretty consistent.

so i figured, "ok, i have 4% loss" since it was 270 3 of those times. then i randomly charged to 100% every few days getting same results. then the weather broke, we had several mornings in the mid to upper 40's. i charged once and got 272 so thinking "ok, close enough to my 270 i call it good". went anther 4 days, charged again and got 275 yesterday and 277 this morning.

garage temp 62º OAT 52º. i have not seen 277 since July (obtw, our warm summer did not start until last week of July and it wasnt very warm either. around here, i consider anything over 75 to be warm)

so, now; after being convinced i knew what i knew and after 19 months and 21,500 miles, it all made perfect sense as well...now i am faced with

**have i only lost temporary capacity? and full charge capacity will come back just in time for cold weather limitations? which i am already comfortable with (actually much much more comfortable with this year now that QC is sitting 2 miles away from longest commute destination?)

** if i am seeing a 3-6% degradation in my relatively mild weather conditions ( Southern CA ALERT i did get readings in the 263 range which i think you will find recognizable when i charged during daylight and temps in the mid 90's which a lot of you would see. it took 4 days for the SOC to get that low despite the 3rd day being the hottest) then to what degree would Phoenix drivers and see and would they ever see a 100% again?

i originally thought AZ owners might see a 7% return on SOC when the weather cools off but now i am thinking it might be more as in nearly double that. i am a bit shocked at how sensitive the battery is to temps and that the optimum point seems to be more in the low 60's range than i previously thought

Every time I see a post about gid count like yours Dave, I have to ask, are you sure your variable gid counts are showing variable battery capacity, or are you actually seeing variable Wh capacity per gid?

If varying gid counts aren't causing the variable charged bar displays that I've described below, what is?

edatoakrun wrote:

"On the afternoon of 9/6 (following a period of the tenth bar disappearing and reappearing on the same "80%" charge, correlating with temperature changes) my 6th temp bar appeared, but for the first time in a few weeks, the 10th charge bar did not disappear. And I have had 10 bars when charging to 80% and they all stayed there, even after the 6th temp bar came on (every day I checked) ever since. So I know that 9/10 bar display change point does not represent an actual fixed amount of kWh charge."


planet4ever wrote:

"I'm afraid I don't follow your argument as to why the change point is not a fixed amount of kWh, but I have no doubt as to the accuracy of the conclusion. Consider a battery so degraded that it now has only 50% of its original capacity. You will still see 12 bars if you charge it completely, but obviously 10 bars will represent far less energy that it did when the battery was new.

Ray"


Edatoakrun wrote

"Because the same amount of kWh, was represented by a variable number of capacity bars, apparently dependent on the battery temperature.

There are multiple possible explanations for this. Two of them (which are not mutually exclusive BTW) are:

This could be because as warmer battery warms it now has a larger capacity (as expected) and each one of the bars in the display now represents the same amount of kWh, but rounded to the nearest ~12th of the total capacity available (or maybe more like ~14th, taking into account the kWh available after the last bar disappears?) it now displays one less bar.

It also could be because the gid count which is (apparently) expressed by the bar display, itself is variable for temperature, and so each gid contains more Wh as the battery warms.

That is why I think those who rely on gid counts for Wh values, could eliminate Wh/gid variability for the same charge (but not for longer term changes in Wh/gid) by watching the gid count of a constant charge level, of a fixed kWh amount, as the battery warms and cools significantly."

http://www.mynissanleaf.com/viewtopic.php?f=30&t=8765&start=200

 

[DaveinOlyWA]

Every time I see a post about gid count like yours Dave, I have to ask, are you sure your variable gid counts are showing variable battery capacity, or are you actually seeing variable Wh capacity per gid?

If varying gid counts aren't causing the variable charged bar displays that I've described below, what is?

take your pick. i personally dont see what the difference is. i guess i am missing something here because the only thing i really see is that the charge level is temperature based. now is that BMS adjusting charge to protect pack? or is it permanent loss due to heat, age, cycling?

** its obvious that GIDs are a representation of charge level and measuring them is not an exact science. well it is, but we dont know the other component effects of that measurement

** its obvious that any temperature variation from the "perfect" temperature has a measurable effect no matter how small

** the TBs are meant to placate the user and should not be used for anything else. the fact that each bar represents different temperature ranges should make that point obvious. its a gauge which historically allows one to glance at it to assess a situation quickly which is nice while driving in traffic. this gauge fails to do so. 6 TBs can mean anything from just above ideal to nearing a level of concern...

** it has already been noticed that reports of bars being lost have slowed considerably and guessing the slightly cooler temps are playing a large part in this.

which if dissecting Nissan's random public comments on the situation could loosely be construed as saying that cooler temps will bring some of those bars back which is something Nissan was obviously well aware of.

the lack of information concerning this phenomena is confusing to me. Nissan must have known that techies, scientists, engineers and DIY'ers would be their primary first user market. to hide something that is so easy to reverse engineer on our own and then continue to cover up after being exposed is weird.

i wish i could say i know what Nissan plans to do. i can only guess the solution will be good enough for us to forget all the stress, hand wringing and bad thoughts that have built up over the past 3 months.

it is well known that we as Humans are reward-oriented and a good enough reward will do exactly that. but during this "black out" period of inaction, Nissan is losing customers. so i am guessing this solution is good enough to bring them back plus a flood of new ones.

the wait is killing me.

 

[edatoakrun]

Every time I see a post about gid count like yours Dave, I have to ask, are you sure your variable gid counts are showing variable battery capacity, or are you actually seeing variable Wh capacity per gid?...

Take your pick. i personally dont see what the difference is...

If you have variable Wh capacity per gid, it is entirely possible you never "lost" much capacity at all.

So there will be none for you to "recover", in the future.

Tick tock has reported gid variability as "...although 80Wh may be the nominal target for 1 gid, it can be off by as much as 10%..."

http://www.mynissanleaf.com/viewtopic.php?f=44&t=9689&hilit=+ticktock" onclick="window.open(this.href);return false;

And I have seen ~11% reduction in my reported battery capacity over the last year, even though actual range tests and recharge times both seem to indicate little or no (observable) loss of battery capacity, over the same time.

http://www.mynissanleaf.com/viewtopic.php?f=31&t=9064&start=30" onclick="window.open(this.href);return false;

So, I wouldn't be at all surprised if my car also had something near an 11% reduction in gid count, which seems to be pretty close to the average reported by gid counters with battery use histories similar to my own.

I'm looking forward to the Phoenix range test results, to see what the range of gid Wh and kW use report variability (if any) is, for a number of different LEAFs with varying gid counts and bar losses.

"DaveinOlyWA"

...the wait is killing me

If many or all other LEAFs' dash, nav screen, and CW energy consumption reports are varying over time, and drifting towards under-reporting energy use, as I believe mine are, I think Nissan has a real PR mess on their hands, which will probably take a long time to straighten out.

Of course, I think this possibility is far preferable to the other one, that LEAF batteries really are losing capacity as rapidly as gid counts and bar displays indicate.

Meanwhile, I'm just enjoying (what I believe, so far...) is my LEAFs ~full battery capacity, whatever the damn numbers say.

 

[DaveinOlyWA]

If you have variable Wh capacity per gid, it is entirely possible you never "lost" much capacity at all.

gee Ed that would be backwards would it not?

if reading say 281 GIDs at 80 watts each = 22480 KW which inself is a question since i dont now or have ever had access to that much. more like 21,250 or so which at 281 GIDs would make a GID = 75.6 watts so when it gets hot and GID count drops but resistance also drops and so when seeing 250 GID its really still

20000 watts because the GID is 80 watts when its hot?

now, that is possible because there is an obvious temperature adjusted "full charge" going on and that makes sense. this is internal circuitry either self adjusting or trying to trick the pack into thinking its fuller than it really is so overcharging does not happen when its hot out.

in the experiment i ran, i tried to plot a trend line but was difficult to extrapolate since i cannot determine internal battery temps and i found that the battery pack reacts relatively slowly to temperature changes that are relatively mild in my case since i could get nothing more than about the mid 90's in ambient temps.

but guessing that most in Phoenix should see at least 7% back when temps mellow into the 70's and could be as much as 12% but with so few data points to consider and a relatively large percentage change within a few i have in the same temperature range could we see ones with the most loss getting most of it back?

 

[mksE55]

If you have variable Wh capacity per gid, it is entirely possible you never "lost" much capacity at all.

gee Ed that would be backwards would it not?

if reading say 281 GIDs at 80 watts each = 22480 KW which inself is a question since i dont now or have ever had access to that much. more like 21,250 or so which at 281 GIDs would make a GID = 75.6 watts so when it gets hot and GID count drops but resistance also drops and so when seeing 250 GID its really still

20000 watts because the GID is 80 watts when its hot?

now, that is possible because there is an obvious temperature adjusted "full charge" going on and that makes sense. this is internal circuitry either self adjusting or trying to trick the pack into thinking its fuller than it really is so overcharging does not happen when its hot out.

in the experiment i ran, i tried to plot a trend line but was difficult to extrapolate since i cannot determine internal battery temps and i found that the battery pack reacts relatively slowly to temperature changes that are relatively mild in my case since i could get nothing more than about the mid 90's in ambient temps.

but guessing that most in Phoenix should see at least 7% back when temps mellow into the 70's and could be as much as 12% but with so few data points to consider and a relatively large percentage change within a few i have in the same temperature range could we see ones with the most loss getting most of it back?

I wish I was as optimistic as yourself. but we have had significant temps. drop here in TX and I dont see any improvement in range. temps were 104-108 6 bars rare 7, now temps 85 and even 60s at night for 2 weeks, still 6 bars and still only getting 55 miles out of 100% charge to LBW with 3.9Kwh driving. So for your theory to hold true. the software must have multiple limiting factors , set Temp to go under and a set amount of time to be under those temps. Seems like wishful thinking. I hate to rain on your parade but to many variables to be possible , and as others have mentioned then why isnt every Leaf affected. seem more plausible that the Heat is hard on the battery chemistry and while some have done ok, others not. maybe the few test batteries were the better ones and now with mass production, the QC of battery maker is less than Stellar. this would fit with less variable. Would be happy to see any improvement in the cooler months but I didnt like the 15% loss with winter as the total affect on the battery now will be 30%, (albeit for just 2 months here in TX,).

 

[TickTock]

I have enough data that a believable trendline is forming (no easy way to plot in google - switch to the compute tab to see/check the linear fit calculations). It looks like on 10/8/2012, I will be at 19.67 capacity which is 7.6% lower then I had on 10/8/2011. This is filtering all the noise and plotting a best-fit linear trendline on the data. I cannot say with surety how much I had lost by 10/8/2011 (it was 4 months old by then) but based on Collected Data, I was down 18% from the numbers reported by new Leaf owners. Note that none of this is dependent on gid accuaracy - just data measured from the wall (the gid-based data is showing a lot of seasonal fluctuations).

 

[edatoakrun]

"mksE55"

I wish I was as optimistic as yourself. but we have had significant temps. drop here in TX and I dont see any improvement in range. temps were 104-108 6 bars rare 7, now temps 85 and even 60s at night for 2 weeks, still 6 bars and still only getting 55 miles out of 100% charge to LBW with 3.9Kwh driving...

Nearly all LEAF owners (except for those who use a great deal of AC in summer, and little heat in winter) will see their range drop as the weather cools, due to the battery's loss of capacity due to the colder battery temperatures while charging, and also due to the lower efficiency factors of driving in colder temperatures.

IMO, despite much speculation, we really don't know if the LEAFs BMS is operating as intended and limiting maximum and minimum charge levels seasonally, or malfunctioning and restricting charging to too low a capacity. There may not even be a seasonal/temperature adjustment, but that would seem to be a poor decision made by Nissan, for a BEV without ATM, designed for the US Southwest market, IMO

And my own observations on my car have pretty well convinced me that the m/kWh and kWh use reports from my LEAF (~11% loss of reported capacity over the last year, but no loss of range) are not accurate. But there could be other explanations for what I've seen. When we get the Phoenix range test results, and other future range test reports, we should know a lot more on this subject.

And only when we find out what the effects of those factors are, will we have much idea of what capacity bar loss means, either in variable capacity of the kWh charge allowed by the BMS, or the underlying rate of battery degradation.

Oh yeah, we also may also hear something on the subject from Nissan, someday...

 

[TickTock]

This morning i re-lost my #12 capacity bar. I had charged to 80% overnight and had all 12 at the end of that charge when I hit the timer override to get a full charge so the bar was lost during the 80-100 charge.

 

[DaveinOlyWA]

If you have variable Wh capacity per gid, it is entirely possible you never "lost" much capacity at all.

gee Ed that would be backwards would it not?

if reading say 281 GIDs at 80 watts each = 22480 KW which inself is a question since i dont now or have ever had access to that much. more like 21,250 or so which at 281 GIDs would make a GID = 75.6 watts so when it gets hot and GID count drops but resistance also drops and so when seeing 250 GID its really still

20000 watts because the GID is 80 watts when its hot?

now, that is possible because there is an obvious temperature adjusted "full charge" going on and that makes sense. this is internal circuitry either self adjusting or trying to trick the pack into thinking its fuller than it really is so overcharging does not happen when its hot out.

in the experiment i ran, i tried to plot a trend line but was difficult to extrapolate since i cannot determine internal battery temps and i found that the battery pack reacts relatively slowly to temperature changes that are relatively mild in my case since i could get nothing more than about the mid 90's in ambient temps.

but guessing that most in Phoenix should see at least 7% back when temps mellow into the 70's and could be as much as 12% but with so few data points to consider and a relatively large percentage change within a few i have in the same temperature range could we see ones with the most loss getting most of it back?

I wish I was as optimistic as yourself. but we have had significant temps. drop here in TX and I dont see any improvement in range. temps were 104-108 6 bars rare 7, now temps 85 and even 60s at night for 2 weeks, still 6 bars and still only getting 55 miles out of 100% charge to LBW with 3.9Kwh driving. So for your theory to hold true. the software must have multiple limiting factors , set Temp to go under and a set amount of time to be under those temps. Seems like wishful thinking. I hate to rain on your parade but to many variables to be possible , and as others have mentioned then why isnt every Leaf affected. seem more plausible that the Heat is hard on the battery chemistry and while some have done ok, others not. maybe the few test batteries were the better ones and now with mass production, the QC of battery maker is less than Stellar. this would fit with less variable. Would be happy to see any improvement in the cooler months but I didnt like the 15% loss with winter as the total affect on the battery now will be 30%, (albeit for just 2 months here in TX,).

maybe every LEAF is not affected but mine certainly is

http://www.mynissanleaf.com/blog.php?u=291&b=171&r=40&start=0" onclick="window.open(this.href);return false;

55 miles @ 3.9 M/k is a GOM figure of 14 usable KW

now i really need to wait until mon or tues to comment, but its looking like the GOM is misleading you as to your real range based on prelim info from the AZ tests that may have proved you have more range than your car is telling you but suppose you dont.

i have weak personal evidence that the car's ability to accept a charge is very dependent on temperatures and you are losing a lot of capacity temporarily because of that high heat.

now, the big question; what can you do about it?

who knows? maybe nothing. if shade is not an option (i dont have it away from home) covered parking, etc.

drive slower. i know you think you will get run over but there are few rear enders that happen from driving 20 mph slower than the rest of the cars on the freeway. your 3.9 miles per KW is not good. i get at least 4.5 miles per k on the freeway by driving 60 mph (which is pretty much the speed limit here but its 70 going south and i still drive 60)

and the temperature thing is still something i am trying to figure out. it does appear to react quickly in some instances, slowly in others and the temperature range that affects charge is MUCH lower than most have anticipated. so in essence, the statement by Nissan that its a "gauge error" can be loosely interpreted as correct.

i fully expect a software adjustment to help address the issue (hopefully soon) but unfortunately, unlike hardware issues, SW adjustments take a lot more time but...


all i can say is if you live in the Pacific Northwest or San Diego or any other mild weather areas and you think you are unaffected, you are dead wrong

**edit**

oh crap. posted wrong link. (too many windows open at one time i guess...) that post was for FB. got right post now

 

[edatoakrun]

I have enough data that a believable trendline is forming (no easy way to plot in google - switch to the compute tab to see/check the linear fit calculations). It looks like on 10/8/2012, I will be at 19.67 capacity which is 7.6% lower then I had on 10/8/2011. This is filtering all the noise and plotting a best-fit linear trendline on the data. I cannot say with surety how much I had lost by 10/8/2011 (it was 4 months old by then) but based on Collected Data, I was down 18% from the numbers reported by new Leaf owners. Note that none of this is dependent on gid accuaracy - just data measured from the wall (the gid-based data is showing a lot of seasonal fluctuations).

But you seem to report that you got 74 miles at 64 mph on yesterday's range test?

https://docs.google.com/spreadsheet/ccc?key=0An7gtcYL2Oy0dHNwVmRkNkFnaEVOQTVENW5mOTZlb0E#gid=1" onclick="window.open(this.href);return false;

 

[TickTock]

That's correct. What's more, my gid count after the 100% charge on the PADT L2 was noticably lower then I get at home. I'll leave it at that - a little teaser until Tony compiles and presents the data. :twisted:

I have enough data that a believable trendline is forming (no easy way to plot in google - switch to the compute tab to see/check the linear fit calculations). It looks like on 10/8/2012, I will be at 19.67 capacity which is 7.6% lower then I had on 10/8/2011. This is filtering all the noise and plotting a best-fit linear trendline on the data. I cannot say with surety how much I had lost by 10/8/2011 (it was 4 months old by then) but based on Collected Data, I was down 18% from the numbers reported by new Leaf owners. Note that none of this is dependent on gid accuaracy - just data measured from the wall (the gid-based data is showing a lot of seasonal fluctuations).

But you seem to report that you got 74 miles at 64 mph on yesterday's range test?

https://docs.google.com/spreadsheet/ccc?key=0An7gtcYL2Oy0dHNwVmRkNkFnaEVOQTVENW5mOTZlb0E#gid=1" onclick="window.open(this.href);return false;

 

[edatoakrun]

I have enough data that a believable trendline is forming (no easy way to plot in google - switch to the compute tab to see/check the linear fit calculations). It looks like on 10/8/2012, I will be at 19.67 capacity which is 7.6% lower then I had on 10/8/2011. This is filtering all the noise and plotting a best-fit linear trendline on the data. I cannot say with surety how much I had lost by 10/8/2011 (it was 4 months old by then) but based on Collected Data, I was down 18% from the numbers reported by new Leaf owners. Note that none of this is dependent on gid accuaracy - just data measured from the wall (the gid-based data is showing a lot of seasonal fluctuations).

I am a bit skeptical (or maybe just jealous...) of those "normalized" results of up to 27kWh capacity.

If capacity varied that much between batteries, Nissan really missed the boat, IMO in not charging for the "optional" higher capacity battery, for those LEAFs...

="TickTock"

This morning I re-lost my #12 capacity bar. I had charged to 80% overnight and had all 12 at the end of that charge when I hit the timer override to get a full charge so the bar was lost during the 80-100 charge.

Interesting.

I'll leave it to you, to summarize what your present and past 12th bar loss results indicate about what range of percentage of actual capacity loss, the loss of that capacity bar may actually represent.

 

[TonyWilliams]

Yes, I will be working on the data compilation from our Sept 15 tests Monday and probably Tuesday. Today, I'm lounging.

I will offer that the data, at a casual glance, suggests that the Gid measurements are flawed between cars. That doesn't mean that our "homemade" devices are wrong, as they merely mimic what the LEAF's automation reports. But, with all cars at the same temperature, at the same place, and the same time, all charged to 100%, that the range for all 12 tested cars failed to accurately reflect that Gid readings are dependable for this job. Whatever instrumentation that Nissan uses (no doubt, the cheapest product they could source for the job) is not a dependable tool for this job, or the programming is suspect, or both.

This should not be a huge surprise. The GoM isn't the only instrument to be proven to not be accurate. Before somebody gets their underwear all bunched up with some "counterpoint" that their back-of-the-napkin calculation, or their breathless starry eyed called to a big wig Nissan exec, says otherwise, I would just ask that you wait a few days for the data from our test. Thanks.