Capacity Loss on 2011-2012 LEAFs

[Herm]

thanks opposum, maybe all you guys could drive down to Casa Grande and do a mass dump of Leafs in the parking lot of the facility (bring a bus to drive everyone back).. that would make a strong point. Write on the windshield how many bars lost, length of ownership and miles.

 

[derkraut]

thanks opposum, maybe all you guys could drive down to Casa Grande and do a mass dump of Leafs in the parking lot of the facility (bring a bus to drive everyone back).. that would make a strong point. Write on the windshield how many bars lost, length of ownership and miles.

Herm: I think your suggestion would be counter-productive. What would it accomplish?

 

[opossum]

Some of us would no longer have the range to drive the cars there, ironically. It would be 53 miles from our house, so we would have to drive pretty conservatively, considering that it's mostly freeway/highway to get there. Given how much time we have wasted over the last several months fighting this issue, including taking time off work to take the car to the dealer THREE times, only to have it tested for hours and be told everything was "normal," we'll just dump the car at the Nissan dealership 10 minutes from the house and let them haul it as promised.

 

[shrink]

Some of us would no longer have the range to drive the cars there, ironically. It would be 53 miles from our house, so we would have to drive pretty conservatively, considering that it's mostly freeway/highway to get there. Given how much time we have wasted over the last several months fighting this issue, including taking time off work to take the car to the dealer THREE times, only to have it tested for hours and be told everything was "normal," we'll just dump the car at the Nissan dealership 10 minutes from the house and let them haul it as promised.

It's a 75 mph speed limit on I-10 down to Casa Grande. I doubt a lot of the affected cars could make it.

 

[GRA]

Some of us would no longer have the range to drive the cars there, ironically. It would be 53 miles from our house, so we would have to drive pretty conservatively, considering that it's mostly freeway/highway to get there. Given how much time we have wasted over the last several months fighting this issue, including taking time off work to take the car to the dealer THREE times, only to have it tested for hours and be told everything was "normal," we'll just dump the car at the Nissan dealership 10 minutes from the house and let them haul it as promised.

It's a 75 mph speed limit on I-10 down to Casa Grande. I doubt a lot of the affected cars could make it.

Does that mean, as it does in Ca., that the unrestricted traffic flow is moving ~80?

 

[GaslessInSeattle]

I agree! I think it would help people more quickly figure out that action is being taken and help focus the topic going forward. the thread should start with a summary of the issues and time line. who wants to do it?

considering the action Nissan is taking and the confusion on this forum, i think we should most definitely start another thread concerning the cars taken to Casa Grande... (is that the right place?)

after all, ALL the current threads are mostly speculation. we have moved on from that stage.

 

[aqn]

What do you guys suppose they're going to do to test those 5 or 6 Leafs in Casa Grande? I mean, I'm confused because they make it sound like it's a mystery to them why these batteries lose capacity and they now have to run tests to find out why. I thought it's already pretty obvious that heat is the primary cause for the loss. I also thought that they've claimed that they already extensively tested the battery in AZ before. So what new information could they get possibly get from these batteries that they couldn't have gotten before?

Sure, I can understand if they missed the mark on a 5-year or 10-year accelerated testing or something like that. But this failure happens in only the first year of ownership. So I'm sure they don't need accelerated testing to figure this out. I'm sure they must have been doing real time testing already for years already, or at least for 1 year before they launch the product, wouldn't you think? After all, they claim that they've been working on their own battery technology for 10+ years or so already, so they know their battery inside out. So well that they're confident they don't need TMS. So well that they didn't hesitate to make AZ their Tier1 state. So how could they have missed this issue so badly that they now need to run additional tests???

Perhaps Nissan did do extensive testing in AZ, but **** happens. Hardware has bugs. Software has bugs. Perhaps Nissan did not expect this occurrence at all and is as surprised as we are. This doesn't excuse Nissan, nor their rather sluggishness out of the block in dealing with this. Also, I completely empathize with people spending close to $30K for a set of wheels that is slowly morphing into a golf cart. But let's keep our eyes on the prize: some kind of satisfactory resolution. One won't get there escalating things too far too early...

 

[GRA]

What do you guys suppose they're going to do to test those 5 or 6 Leafs in Casa Grande? I mean, I'm confused because they make it sound like it's a mystery to them why these batteries lose capacity and they now have to run tests to find out why. I thought it's already pretty obvious that heat is the primary cause for the loss. I also thought that they've claimed that they already extensively tested the battery in AZ before. So what new information could they get possibly get from these batteries that they couldn't have gotten before?

Sure, I can understand if they missed the mark on a 5-year or 10-year accelerated testing or something like that. But this failure happens in only the first year of ownership. So I'm sure they don't need accelerated testing to figure this out. I'm sure they must have been doing real time testing already for years already, or at least for 1 year before they launch the product, wouldn't you think? After all, they claim that they've been working on their own battery technology for 10+ years or so already, so they know their battery inside out. So well that they're confident they don't need TMS. So well that they didn't hesitate to make AZ their Tier1 state. So how could they have missed this issue so badly that they now need to run additional tests???

Perhaps Nissan did do extensive testing in AZ, but **** happens. Hardware has bugs. Software has bugs. Perhaps Nissan did not expect this occurrence at all and is as surprised as we are. This doesn't excuse Nissan, nor their rather sluggishness out of the block in dealing with this. Also, I completely empathize with people spending close to $30K for a set of wheels that is slowly morphing into a golf cart. But let's keep our eyes on the prize: some kind of satisfactory resolution. One won't get there escalating things too far too early...

The problem being that Nissan essentially brushed off owners' concerns before this was escalated. People wanted to be and tried to be nice - it didn't work. Nissan's still not being very proactive, but at least they're now responding with something other than denial.

 

[thankyouOB]

nothing Nissan does will make some of you happy, apparently.
I get that this sucks but
testing is going on.
loaners are here. with walk around and gas money.
maybe more can get in on it.
there will be answers, presumably.

and GRA, who doesnt own a Leaf, keeps on putting on his troll suit to pore it on. I guess that will continue until we all agree just how right he is to be waiting for his perfect EV.
Meanwhile, despite his signer he ignores the facts; by a very large margin, a majority of commutes in the USA work fine in a Leaf, even a degraded one going uphill in the winter.

 

[Herm]

Thanyou, put GRA on ignore before you get an ulcer.

Just because the speed limit is 75 does not mean you cant slow down to 55 on the right hand lane. No, you wont get rammed down from behind.

 

[thankyouOB]

Thanyou, put GRA on ignore before you get an ulcer.

Just because the speed limit is 75 does not mean you cant slow down to 55 on the right hand lane. No, you wont get rammed down from behind.

you be funny, Herm, even if your politics are from the get-off-my-lawn party.

me? get an ulcer. this is how I dont get an ulcer. I just finished painting all the trim on the house, this is recreation.
and GRA is the one, true, fun troll.

 

[pchilds]

It is impossible to be cut off when, they are going 20-30 mph, faster than you. They think they are cutting you and it is two-three-four car lengths. :lol:

 

[LEAFer]

Some of us would no longer have the range to drive the cars there, ironically. It would be 53 miles from our house, so we would have to drive pretty conservatively, considering that it's mostly freeway/highway to get there. Given how much time we have wasted over the last several months fighting this issue, including taking time off work to take the car to the dealer THREE times, only to have it tested for hours and be told everything was "normal," we'll just dump the car at the Nissan dealership 10 minutes from the house and let them haul it as promised.

It's a 75 mph speed limit on I-10 down to Casa Grande. I doubt a lot of the affected cars could make it.

All (five or six selected) owners should drive his/her respective car to Casa Grande for drop-off. Bring the Nissan supplied Roadside Assistance Tel# with you Make sure you follow all traffic laws and signage

 

[mark1313]

I wish I could talk to someone who was involved in testing the Leaf in the Phx Az area..
I would like to compare my routine with the Leaf on a daily basis to their routine in testing the car here..

I would be curious in how long of drives they did on their testing on a daily basis..I need 80 miles..
Where did they park the cars doing the hot summer days ..Mine is parked out in the sun for 6 hours a day,that blacktop really heats up and we avg. 110 in the shade..
Where did they recharge the cars doing the summer ....I charge @ 11pm to 230 am in the garage,avg. temp 96 ..
I never read about 80% battery charges before I bought the car and was not told about about it at the dealer..The dealer went over everything with me that lasted close to 2 hours..I told the salesman this car was going to be the workhorse with 80 mile avg. drives ,his reply was this car was the right choice and I should have years of problem free driving..
I need 100% charges on work days,80% on off days..
Im @ 17000 miles, 6M/KWH... I had one headlight replaced..I lost 2 battery capacity bars in a 45 day period I had 3 battery ckecks done,all passed with 5 stars..

 

[LEAFfan]

My guess is that they will compare these 5 Leafs to their previously tested vehicles, and they will come back with new batteries.

If that's ALL that happens, it's not enough (unless there are some magic chemistry tweaks), because owners will just find themselves in the same place in 18 months time.

I believe they may just give them new packs too, but it won't be 18 months until they've lost a bar or two...most have lost two bars in about a year. Scott lost his third bar in just 13 months! And one guy I know had a brand new battery pack as a replacement 7 months ago (can't remember what was wrong with it) and has already lost a bar! It was only in about two and a half months of heat.

 

[LEAFfan]

It WOULD be nice to know the magic number... the number of degrees of ambient temperature where it's no longer safe for the battery, whether it's outside in the blazing sun, or outside in the shade, or in a garage. The manual says 120 degrees for 24 hours, but we're not hitting that for a lot of people, yet still the battery capacity losses. We need to know the magic number.

Can't find the reference right now, but similar battery chemistry to the LEAF's is recommended to keep the battery between 14-86 degrees F.

JP, I saw that too somewhere where our battery pack starts to degrade above 86F.

 

[mwalsh]

JP, I saw that too somewhere where our battery pack starts to degrade above 86F.

Oh, crap. If that's true. We're all doomed! Doomed I tells ya!

 

[JPWhite]

JP, I saw that too somewhere where our battery pack starts to degrade above 86F.

Oh, crap. If that's true. We're all doomed! Doomed I tells ya!

Found this reference at Pike Research

http://www.pikeresearch.com/blog/lithium-ion-batteries-can’t-stand-the-heat

They are talking battery temps, not ambient. I've nothing to base the following on except a gut feel, but I believe the 'tipping point' is higher than 86 where degradation takes off, probably just shy of 100.

I've prepared a spreadsheet to try and estimate when a LEAF will reach end of life, parameters are annual degradation percentage, range when new and commute distance. Feel fre to download and play with it, it won't convert to a google doc.
https://docs.google.com/open?id=0B39AnLYYoeBpMGY3VEtnMWF5c00

 

[DaveEV]

Can't find the reference right now, but similar battery chemistry to the LEAF's is recommended to keep the battery between 14-86 degrees F.

JP, I saw that too somewhere where our battery pack starts to degrade above 86F.

While there is probably a temperature at which degradation really takes off, in general the colder the battery, the longer it will last.

For example, look at the chart ydnas7 posted here for Lithium NCA battery.

http://img259.imageshack.us/img259/3326/ncai.jpg" onclick="window.open(this.href);return false;

The other interesting tidbit to pull from this study is that the lower SOC is extremely beneficial to battery life. Storing the NCA battery at 40% SOC / 35C results in the same degradation rate as storage at 80% SOC / 17C. Also, using "just-in-time" charging to 100% results in basically the same degradation rate as just-in-time charging to 80%. Nissan clearly hasn't educated customers well enough on the potential benefits of using and end-only-timer.

So set those end-timers only, people!

I am tempted to push my 80% end-timer out from stopping around ~5am closer to my usual 8-9am departure time even though that would increase my cost to charge about 20%. Doing so would get me 3-4 hours/day less time spent at 80% SOC instead spent at 30-50%. Storage at 40% SOC is about half as bad as storage at 80% SOC which is about half as bad as storage at 100% SOC.

Looking at the EV Project data, it's scary how many people are charging between 9pm-12am (leaving 8 hours storage at "full") and how many are charging to 100% (~65% Phoenix EV Project participants and ~50% Tuscon EV Project participants).

At the same time - the difference between 80%/100% charging habits don't seem to have a significant effect on real-life LEAFs in hot-weather climates like AZ which is a bit of a mystery as in theory, storage at 80% should cut degradation rate in half compared to 100% (perhaps less in the LEAF since 100% is really only ~94% but it should still be easily seen).

Edit: Found the source of the image - comes from a NREL study: http://www.nrel.gov/vehiclesandfuels/energystorage/pdfs/53817.pdf" onclick="window.open(this.href);return false;

 

[Volusiano]

Looking at the EV Project data, it's scary how many people are charging between 9pm-12am (leaving 8 hours storage at "full")

I don't blame people for wanting to plug in right away after they get home and charge to 80% between 9pm-12am. They want their car to be ready at full 80% capacity as soon as possible to serve them whenever needed. After all, Nissan never said anything about doing that being bad for the battery. All Nissan recommends is 80% charge and you can't blame people for doing things Nissan never said is bad for the battery.

I, for one, would not have become an early adopter if Nissan has disclosed all this stuff about waiting for the battery to cool down before charging, or that 80% charge stored all night long is bad, etc. There's a balance before too many charging requirements becomes a nuisance and not worth using. After all, people buy the car to serve them, not the other way around.

But since Nissan chose to not disclose or require people to do any of these practices, it's on Nissan's head to be held responsible if these practices that Nissan condones (by not saying anything about them) becomes detrimental to battery life.