Capacity Loss on 2011-2012 LEAFs

[TonyWilliams]

The remaining energy at turtle cut-off is about 0.5 kWh, not 3.

 

[vegastar]

Just a little tidbit from this study:

http://www.nrel.gov/vehiclesandfuels/energystorage/pdfs/53817.pdf" onclick="window.open(this.href);return false;

"...fade rates are some 25% to 30% lower when battery operation is restricted to 80% SOCmax versus allowing full utilization up to 100% SOCmax. The just-in-time charging scenario V, however, shows little sensitivity to SOCmax as that scenario keeps the average SOC low regardless of SOCmax limit (Table 2). The result points to a tangible benefit to battery life by delaying the beginning of charge until several hours before the next driving trip. In practice, it will be difficult to realize the full benefits of just-in-time charging without good knowledge of when the next driving trip will occur."

I like this idea from the study:

"Seasonal adjustments may increase SOCmax during cold winter months
to help compensate for sluggish battery performance and
vehicle electric range at cold temperatures."

Below 10C the charge could go all the way up to 4.2V with little effect on the battery life, but could somehow compensate for reduced capacity at low temperatures and heater energy consumption.

 

[TonyWilliams]

Below 10C the charge could go all the way up to 4.2V with little effect on the battery life, but could somehow compensate for reduced capacity at low temperatures and heater energy consumption.

And stopped at 4v (or discharged to 4v) during higher temperatures.

 

[Joeviocoe]

what are your expectations in Florida for next year, in those same terms? (xx% 1.x - FL 2013)
Thanks.

I wouldn't expect any Florida LEAF to survive past the 20,000 mile mark without losing one bar, or we can, pretty much, throw the Arrhenius equation out the window as a predictive factor. For the typical 12,000 mile/year early adopter that means the first bar will fall next spring.

Even with "normal" temperatures, a t^(1/2) degradation rate suggests a 16% loss at the three year or 36,000 mile mark (to reach 20% at 5 years). For any Florida LEAF to reach 3.75 years without losing a bar would be really extraordinary.

Thanks. So we'll see how it plays out.... I'll be watching Florida closely. Like Bush v. Gore, close.

 

[Herm]

Agreed, but if Nissan were to do this they, would have to stop advertising their vaulted 73 mile range as this would be affected by only an 80% charge. I'm not entirely sure this wouldn't also affect the EPA posting as that should be tied to the amount of charge too.

Tesla does this, standard mode charge (80%) is default and extended range (100%) is optional.. do they advertise the 80% or the 100% charge?, what does the EPA test?

I expect the 2013 Leaf will implement this, I hope they do.

 

[Weatherman]

I wouldn't expect any Florida LEAF to survive past the 20,000 mile mark without losing one bar, or we can, pretty much, throw the Arrhenius equation out the window as a predictive factor. For the typical 12,000 mile/year early adopter that means the first bar will fall next spring.

Thanks. So we'll see how it plays out.... I'll be watching Florida closely. Like Bush v. Gore, close.

I will add one exception...

Any Florida LEAF owner, who has been very diligent to maintain a low SOC on their battery, through the judicious use of just-in-time and only-as-much-as-needed charging, may see the first bar fall after 20,000 miles. At least that's my hope. I plan to use that charging method on my own LEAF. I won't know if it makes any difference until the first bar falls, or the 20,000 mile mark is reached. I don't expect to reach 20,000 miles until June 2014, so this may be a very short or a very long experiment.

 

[DesertDenizen]

I do just in time charging, never exceed 80%, never QC, always in Eco, don't exceed 45 mph, never below two SOC bars. I lost my first capacity bar at 6,881 miles.

 

[Stoaty]

I do just in time charging, never exceed 80%, never QC, always in Eco, don't exceed 45 mph, never below two SOC bars. I lost my first capacity bar at 6,881 miles.

What is the average SOC (Gids or number of fuel bars) for you Leaf?

 

[Weatherman]

I do just in time charging, never exceed 80%, never QC, always in Eco, don't exceed 45 mph, never below two SOC bars. I lost my first capacity bar at 6,881 miles.

Then it may be a very short experiment.

 

[DesertDenizen]

As noted I charge just before I leave, so the Leaf never sits at 80%. I have never been below 2 SOC bars, so it sits at between 2 and 8 bars. Most commonly it is at 5-7 bars. I don't drive that much.

 

[DaveEV]

I do just in time charging, never exceed 80%, never QC, always in Eco, don't exceed 45 mph, never below two SOC bars. I lost my first capacity bar at 6,881 miles.

Have you performed a range test or a turtle to 100% from-the-wall energy measurement? Either method (or preferably both) appear to give a much more accurate indicator of actual battery capacity since we already know that the capacity bars appear to be pessimistic compared to what the service manual says.

 

[JeremyW]

I think the point may be that, if you have a very good idea of when and how much you'll be driving the car, you can maintain a low SOC (say around 30%) most of the time, and there's a benefit in doing so. A few hours before you are ready to leave you charge the battery, but only up to the amount you'll need. So, for a 15 mile trip, you might charge it up to 50%. Or, for a 30 mile trip, you might charge up to 65%

This is what I'm doing. It's practical for my town since most of my driving is in a ~10 mile radius. Dealing with stopping the charge at the right (low) SOC is a bit of a pain though. We need better charge timers and consumer education. You can follow what I've done in my maintaining low SOC to preserve battery life thread. To what extent this will help reduce loss I won't really know for a few years, I think.

 

[Weatherman]

I’m lucky that I don’t have to worry about TOU rates (it’s 11 cents/kWh, 24-hours a day), so I just set the charge timer to 80% and the end time about an hour after I normally leave in the morning. By the time I’m ready to leave, I can just unplug and the charge level will be close to the 8 bars I want for my 34-mile commute.

 

[jspearman]

Was just contacted by an arbitrator at Nissan to review the results of the testing they did on Wednesday. As you can imagine, all is normal, it's new technology, etc. They want to keep an eye on things and for me to bring it in again down the road. I told her I'm not happy with that answer and that I would be interested in a 2-year lease, but no longer want to be an owner, that by the time our car is 3 years old it will no longer be useful in Phoenix for anything but the shortest drives. I told her I knew the owners who took lemon law protection and didn't want to take them, or myself, down that road, so we'll see what happens.

I didn't expect it be easy, but I sort of hoped it would be.

 

[Stoaty]

Was just contacted by an arbitrator at Nissan to review the results of the testing they did on Wednesday. As you can imagine, all is normal, it's new technology, etc. They want to keep an eye on things and for me to bring it in again down the road. I told her I'm not happy with that answer and that I would be interested in a 2-year lease, but no longer want to be an owner, that by the time our car is 3 years old it will no longer be useful in Phoenix for anything but the shortest drives. I told her I knew the owners who took lemon law protection and didn't want to take them, or myself, down that road, so we'll see what happens.

Looks like the stonewalling is still going on. Disappointing to see this, after it looked hopeful. Nissan has yet to restore my faith that they will take care of the early adopters in hot areas when they knew there would be accelerated battery capacity loss. I'm not sure what the point is for having a global advisory board when Nissan doesn't do the right thing on a major issue like this.

 

[GRA]

Was just contacted by an arbitrator at Nissan to review the results of the testing they did on Wednesday. As you can imagine, all is normal, it's new technology, etc. They want to keep an eye on things and for me to bring it in again down the road. I told her I'm not happy with that answer and that I would be interested in a 2-year lease, but no longer want to be an owner, that by the time our car is 3 years old it will no longer be useful in Phoenix for anything but the shortest drives. I told her I knew the owners who took lemon law protection and didn't want to take them, or myself, down that road, so we'll see what happens.

Looks like the stonewalling is still going on. Disappointing to see this, after it looked hopeful. Nissan has yet to restore my faith that they will take care of the early adopters in hot areas when they knew there would be accelerated battery capacity loss. I'm not sure what the point is for having a global advisory board when Nissan doesn't do the right thing on a major issue like this.

Indeed, they just keep digging. I'm just about at the point where I conclude that everything they've said so far is all window-dressing, and they aren't going to change their behavior. Sad, but at least there are a fair number of options from other companies now.

 

[jspearman]

Was just contacted by an arbitrator at Nissan to review the results of the testing they did on Wednesday. As you can imagine, all is normal, it's new technology, etc. They want to keep an eye on things and for me to bring it in again down the road. I told her I'm not happy with that answer and that I would be interested in a 2-year lease, but no longer want to be an owner, that by the time our car is 3 years old it will no longer be useful in Phoenix for anything but the shortest drives. I told her I knew the owners who took lemon law protection and didn't want to take them, or myself, down that road, so we'll see what happens.

Looks like the stonewalling is still going on. Disappointing to see this, after it looked hopeful. Nissan has yet to restore my faith that they will take care of the early adopters in hot areas when they knew there would be accelerated battery capacity loss. I'm not sure what the point is for having a global advisory board when Nissan doesn't do the right thing on a major issue like this.

She said she would get back to me next week, but wasn't sure what she could do. I find it confusing, since she is the arbitrator working for Nissan and should know immediately what's on the table, at least on Nissan's side of the equation. It's disappointing and having the car checked again felt like a complete waste of time.

 

[Nubo]

She said she would get back to me next week, but wasn't sure what she could do. I find it confusing, since she is the arbitrator working for Nissan and should know immediately what's on the table...

Sounds like when the salesman has to go "consult with my sales manager", as if it's his first day on the job... :roll: :lol:

 

[Joeviocoe]

Larger view

Made some serious updates to the dynamic Spreadsheet. It now has a more complete Google map which geolocates all reported Leafs with battery capacity loss, and displays detailed information about each report upon mouse hover.
The other tabs will give you a bigger map, as well as the source data and formulae.

Please let me know if the interface is painfully slow. There is now a LOT of cross-calculations and external website updating going on.

Please check it out on my link below and let me know what you think... thanks.

 

[spooka]

Was just contacted by an arbitrator at Nissan to review the results of the testing they did on Wednesday. As you can imagine, all is normal, it's new technology, etc. They want to keep an eye on things and for me to bring it in again down the road. I told her I'm not happy with that answer and that I would be interested in a 2-year lease, but no longer want to be an owner, that by the time our car is 3 years old it will no longer be useful in Phoenix for anything but the shortest drives. I told her I knew the owners who took lemon law protection and didn't want to take them, or myself, down that road, so we'll see what happens.

I didn't expect it be easy, but I sort of hoped it would be.

Thanks again for the continued updates.

I wonder if there should be a specific thread for these reports.

Did you happen to find out what your remaining capacity is? I'm not asking you to disclose a number if you have one. Just curious if you got the info. I will be asking them for this info.

My plan, when I receive the above response from them next week after I bring in Sonic, is to state that I am reactivating my BBB case immediately and requesting BBB arbitration per the AZ lemon law. I want to get to the bottom line on this one way or the other so we can all stop wasting our time. I'm game. I wonder if they will be.