How should Nissan respond to dropping capacity?

[KJD]

They cant afford to damage their global investment.. so expect a reaction soon. I'm sure they are following this forum avidly now.

Many people follow this thread, and if the goal was to be heard, we may have shot way past the target. Although I believe that many folks would find more transparency desirable and comforting, this is a competitive industry. If Nissan was indeed temporarily restricting maximum state of charge during hot weather to help protect the battery, I wouldn't expect to see public disclosure of such behavior. Personally, and based on the few data points we have, I believe that it's happening. This could account for up to 5 - 10% of battery capacity. Again, it's just a guess, and depending on the condition of the pack, it might not be enough to bring the lost capacity bars back come fall and winter. I think virtually everyone on this forum is level-headed, and would like to see this program succeed. Let's approach it from that angle.

Should be easy enough to test this theory.

Take a car that has "lost capacity" and run the car down to 50% SOC.

Park the car in an air conditioned shop and run the shop air conditioner on max to cold soak the car down to 72 F or lower. I would guess 24 hours would be long enough.

After 24 hours of cold soaking. Charge the car to 100% SOC and read the GID number and pack voltage.

[surfingslovak]

This is a possibility. Can this be confirmed by checking the battery capacity of a "new" Leaf in AZ or TX ??

There was a 2-month old Leaf in Texas, which was reading 265 Gids, a 6% reduction of capacity. Another data point is a Leaf in Seattle, which saw 10% capacity reduction (252 Gids) following multiple QCs and nine temperature bars a day earlier.

Park the car in an air conditioned shop and run the shop air conditioner on max to cold soak the car down to 72 F or lower. I would guess 24 hours would be long enough.

After 24 hours of cold soaking. Charge the car to 100% SOC and read the GID number and pack voltage.

Yes, great idea, this should help confirm the behavior, if it existed. It's worth noting that we don't know how long the car needs to spend away from heat sources.

[CarZin]

I didnt see this posted. I must have missed it, because I'm not sure how a Volt owner would post something about a Leaf that is over a week old...

Nissan Responds:
http://www.greencarreports.com/news/107 ... n-responds" onclick="window.open(this.href);return false;

[RegGuheert]

Should be easy enough to test this theory.

Take a car that has "lost capacity" and run the car down to 50% SOC.

Park the car in an air conditioned shop and run the shop air conditioner on max to cold soak the car down to 72 F or lower. I would guess 24 hours would be long enough.

After 24 hours of cold soaking. Charge the car to 100% SOC and read the GID number and pack voltage.

Except that I suspect the algorithm includes a running average of temperatures over the past few days or a week.

[myleaf]

This is a possibility. Can this be confirmed by checking the battery capacity of a "new" Leaf in AZ or TX ??

There was a 2-month old Leaf in Texas, which was reading 265 Gids, a 6% reduction of capacity. Another data point is a Leaf in Seattle, which saw 10% capacity reduction (252 Gids) following multiple QCs and nine temperature bars a day earlier.

Park the car in an air conditioned shop and run the shop air conditioner on max to cold soak the car down to 72 F or lower. I would guess 24 hours would be long enough.

After 24 hours of cold soaking. Charge the car to 100% SOC and read the GID number and pack voltage.

Yes, great idea, this should help confirm the behavior, if it existed. It's worth noting that we don't know how long the car needs to spend away from heat sources.

Both the TX and WA datapoints noted capacity reduction after multiple QCs. It would be good info to know if and how long it took for capacity to recover for a car operating in a cool environment.

[edatoakrun]

Should be easy enough to test this theory.

Take a car that has "lost capacity" and run the car down to 50% SOC.

Park the car in an air conditioned shop and run the shop air conditioner on max to cold soak the car down to 72 F or lower. I would guess 24 hours would be long enough.

After 24 hours of cold soaking. Charge the car to 100% SOC and read the GID number and pack voltage.

Except that I suspect the algorithm includes a running average of temperatures over the past few days or a week.

...or a few weeks, or a month, or a year, or even longer.

Which is why I'd encourage all LEAF owners with the opportunity to monitor their available battery capacity, keep records from the earliest available time possible, and also note to both ambient and battery (bar status) temperature.

If you have a gid/SOC meter, use it. If you don't, Id suggest a series of capacity tests using Carwings, such as:

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

[phxsmiley]

Is there an email address or some avenue to complain to someone knowledgeable at Nissan about this early capacity loss issue? I think our only avenue is the dealership, but they don't have the bigger picture here. It seems like we should be getting a little more vocal about it, I'm just so disappointed.

[surfingslovak]

Which is why I'd encourage all LEAF owners with the opportunity to monitor their available battery capacity, keep records from the earliest available time possible, and also note to both ambient and battery (bar status) temperature.

If you have a gid/SOC meter, use it. If you don't, Id suggest a series of capacity tests using Carwings, such as:

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

That's great advice.

Is there an email address or some avenue to complain to someone knowledgeable at Nissan about this early capacity loss issue? I think our only avenue is the dealership, but they don't have the bigger picture here. It seems like we should be getting a little more vocal about it, I'm just so disappointed.

Given the amount of scrutiny this thread gets, you can be sure that you've been hard. If you wanted to go beyond that, I would suggest that you gave their support line a call: 1-877-664-2738. If you were on Facebook, it might make sense to send a private message to the staff running the Nissan Leaf page.

[shrink]

Is there an email address or some avenue to complain to someone knowledgeable at Nissan about this early capacity loss issue? I think our only avenue is the dealership, but they don't have the bigger picture here. It seems like we should be getting a little more vocal about it, I'm just so disappointed.

Leafkabob and I are trying to organize a Phoenix area discussion group about how best to express our concerns to Nissan. One of us will PM you with some details.

[DesertDenizen]

Another 100 degree day here in Tucson, and this thread has me counting the bars every time I start up now that I am approaching one year with my Leaf. Still love it though.