Capacity Loss on 2011-2012 LEAFs

[Stoaty]

Here is an article in English which includes that picture: Why Did Nissan Develop an EV Battery?. FWIW, the article also says:

A battery that can control its heating without a cooling mechanism is also longer lasting, since the biggest cause of a battery's lifetime being shortened is overheating.

Is this really something Nissan wants to be drawing attention to now? :twisted:

PS jspearman just reported loss of second capacity bar.

 

[Nubo]

***

 

[edatoakrun]

Here is an article in English which includes that picture: Why Did Nissan Develop an EV Battery?. FWIW, the article also says:

A battery that can control its heating without a cooling mechanism is also longer lasting, since the biggest cause of a battery's lifetime being shortened is overheating.

Is this really something Nissan wants to be drawing attention to now? :twisted:

PS jspearman just reported loss of second capacity bar.

What do you suppose "adjustment of the battery’s internal resistance" means?

Could this be the LEAFs means of limiting total charge at higher temperatures, and/or the reason TickTock has observed variability of gid Wh values?

It sounds like Nissan was far more concerned about the effects of heating the battery by internal resistance, than by high ambient temperatures.

A battery without a cooling system?

...When Leaf was released, possibly one aspect of its technology surprised other carmakers’ engineers the most: Nissan Leaf’s battery has no cooling system. To achieve this, the temperature is controlled by adjustment of the battery’s internal resistance, ...

A battery that can control its heating temperature without a cooling mechanism is also longer lasting, since the biggest cause of a battery’s lifespan being shortened is overheating. In other words, having a cooling system to lower the temperature of a battery in case of overheating has adverse effects on the battery’s durability – it’s better to engineer a battery system that works to avoid overheating to begin with...

 

[shrink]

Mark me down as 2 bars lost. 14,180 miles. The band plays on.

That sucks. Sorry to hear that, but the Titanic reference made me smile.

Let me know if you want to test drive my Volt one of these days...

 

[RegGuheert]

Here is an article in English which includes that picture: Why Did Nissan Develop an EV Battery?. FWIW, the article also says:

A battery that can control its heating without a cooling mechanism is also longer lasting, since the biggest cause of a battery's lifetime being shortened is overheating.

What do you suppose "adjustment of the battery’s internal resistance" means?

I suppose it means designing a battery so that it has a very low electrical resistance as well as a low thermal resistance to ambient.

It sounds like Nissan was far more concerned about the effects of heating the battery by internal resistance, than by high ambient temperatures.

Agreed. And I really like this approach, personally. However, the limitation of this approach is that you cannot effectively use the battery chemistry in an ambient environment which, in itself, equates to "overheating".

 

[DaveinOlyWA]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

makes me think that maybe Nissan was unprepared but then again, if the recent weather pushed several cars over the top that would imply that "cooler" areas like CA's LA Valley areas would only be in the "normal" degradation range.

i am running an experiment and since i am leasing i have decided to literally throw my LEAF into the fire and see what comes out on the other end.

the "heat" part of the experiment will be finished tomorrow and wont know much for sure until we get our cool down which might not be for a week or so but since the final phase of the test will be charging when cool which will be done at night hopefully i can sneak something in quickly

 

[vrwl]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

makes me think that maybe Nissan was unprepared but then again, if the recent weather pushed several cars over the top that would imply that "cooler" areas like CA's LA Valley areas would only be in the "normal" degradation range.

i am running an experiment and since i am leasing i have decided to literally throw my LEAF into the fire and see what comes out on the other end.

the "heat" part of the experiment will be finished tomorrow and wont know much for sure until we get our cool down which might not be for a week or so but since the final phase of the test will be charging when cool which will be done at night hopefully i can sneak something in quickly

Good luck, let us know how it all turns out!

 

[DaveinOlyWA]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

makes me think that maybe Nissan was unprepared but then again, if the recent weather pushed several cars over the top that would imply that "cooler" areas like CA's LA Valley areas would only be in the "normal" degradation range.

i am running an experiment and since i am leasing i have decided to literally throw my LEAF into the fire and see what comes out on the other end.

the "heat" part of the experiment will be finished tomorrow and wont know much for sure until we get our cool down which might not be for a week or so but since the final phase of the test will be charging when cool which will be done at night hopefully i can sneak something in quickly

Good luck, let us know how it all turns out!

barely half down but already some interesting results. here's a pic taken after traveling less than one block after a full charge

what is wrong here? i definitely felt it right away which is why i took the picture

 

[RegGuheert]

what is wrong here? i definitely felt it right away which is why i took the picture

I don't see it. It all looks normal to me.

 

[surfingslovak]

what is wrong here? i definitely felt it right away which is why i took the picture

Shouldn't have that many regen bubbles.

 

[RegGuheert]

here's a pic taken after traveling less than one block after a full charge

Did you forget to reset your trip odometer?

 

[jspearman]

Mark me down as 2 bars lost. 14,180 miles. The band plays on.

That sucks. Sorry to hear that, but the Titanic reference made me smile.

Let me know if you want to test drive my Volt one of these days...

My wife wrote a book on Titanic, and it seems sadly apropos.

Thanks for the Volt offer, but I test drove one right after they arrived in Phoenix and I liked it, but we had just bought the Leaf a couple of months earlier. I think we'll be trading in our Honda soon for one, but I'll ride out the Leaf situation until some sort of resolution, then we'll probably trade it, too.

 

[DaveinOlyWA]

what is wrong here? i definitely felt it right away which is why i took the picture

Shouldn't have that many regen bubbles.

on a 100% charge i am usually almost to Pacific Ave before i get "any" regen bubbles.

i reset my trip odometer daily. the miles are what was driven in the morning before the charge session was started

details

http://www.mynissanleaf.com/blog.php?u=291&b=171&r=41#r41" onclick="window.open(this.href);return false;

 

[LEAFfan]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

Last year, we had 33 days of 110 or higher which was a record. This year, it's only 22 so far. The 30-year average is 19.

 

[shrink]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

Last year, we had 33 days of 110 or higher which was a record. This year, it's only 22 so far. The 30-year average is 19.

I'm not sure if he was referring to mine or not, but I posted something a few days ago about the heat. I linked to a different article, but here's a similar one that was published on 8/14/2012:

http://www.azcentral.com/news/articles/20120814phoenix-area-record-breaking-heat-wave-to-continue-abrk.html" onclick="window.open(this.href);return false;

Aug. 7, Phoenix Sky Harbor International Airport, where the official temperatures are tracked, hit 112, which tied the previous record set in 1905.

On Wednesday, the Valley was 3 degrees hotter than the previous record set at 113 degrees in 1991.

On Thursday, the official temperature crept past the record from 2003 when it hit 114.

On Sunday, the recorded temperature of 115 surpassed the record of 114 set in 2007.

On Monday, the Valley felt a high of 115, which is 2 degrees warmer than the previous record of 113 set in 2003, Kuhlman said.

But we're talking 130-140, like Dubai, right. TMS? We don't need no stinking TMS.

 

[Weatherman]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

Last year, we had 33 days of 110 or higher which was a record. This year, it's only 22 so far. The 30-year average is 19.

Here's another reference for this year's excessive heat event:

http://www.wrh.noaa.gov/psr/pns/2012/August/augheat_2012.php" onclick="window.open(this.href);return false;

 

[Soviet]

I'm in San Antonio, Texas & one week after I came back from Central Asia last month, I noticed that we lost 1 battery capacity bar at just short of 16,000 miles. It's been holding steady since & I hope it stays there, quite frankly.

No discernible loss in actual range....it's still working well for my mom's commute.

We charge to 100%.

 

[DaveinOlyWA]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

Last year, we had 33 days of 110 or higher which was a record. This year, it's only 22 so far. The 30-year average is 19.

Here's another reference for this year's excessive heat event:

http://www.wrh.noaa.gov/psr/pns/2012/August/augheat_2012.php" onclick="window.open(this.href);return false;

yep that the one!! 7 daily high records set in 15 days and its not like any of them were abnormally low to begin with!

 

[ALLWATZ]

Aug. 7, Phoenix Sky Harbor International Airport, where the official temperatures are tracked, hit 112, which tied the previous record set in 1905.

On Wednesday, the Valley was 3 degrees hotter than the previous record set at 113 degrees in 1991.

On Thursday, the official temperature crept past the record from 2003 when it hit 114.

On Sunday, the recorded temperature of 115 surpassed the record of 114 set in 2007.

On Monday, the Valley felt a high of 115, which is 2 degrees warmer than the previous record of 113 set in 2003, Kuhlman said.

But we're talking 130-140, like Dubai, right. TMS? We don't need no stinking TMS.

Ahh, to be that cool. Temps in the Coachella Valley:
Aug 7-113
Weds-114
Thurs-110
Sunday-116
Monday-119
All but one higher than Phoenix and those highs didn't even set records. Lightweights!

 

[vrwl]

just a note; someone posted somewhere else that Phoenix went thru hottest 15 days of August in their history with SEVERAL daily highs set during the period.

makes me think that maybe Nissan was unprepared but then again, if the recent weather pushed several cars over the top that would imply that "cooler" areas like CA's LA Valley areas would only be in the "normal" degradation range.

i am running an experiment and since i am leasing i have decided to literally throw my LEAF into the fire and see what comes out on the other end.

the "heat" part of the experiment will be finished tomorrow and wont know much for sure until we get our cool down which might not be for a week or so but since the final phase of the test will be charging when cool which will be done at night hopefully i can sneak something in quickly

Good luck, let us know how it all turns out!

barely half down but already some interesting results. here's a pic taken after traveling less than one block after a full charge

what is wrong here? i definitely felt it right away which is why i took the picture

If it's allowing regeneration that soon after a full charge to 100%, it sort of makes me wonder if there IS some sort of charging limitation going on with the BMS due to the ambient heat. So it's not REALLY at a 100% charge, thus allowing you to regen some energy that soon after you start your driving. Hmmm, as the worm turns....