Meeting with Nissan, Phoenix, Jan 8, 2013, 6pm, drinks prior

[Ingineer]

Ok, that sounds logical. So, at 393.5 volts and 1C (24kW load), I should see about 60 amps, and as the voltage drops below 300 volts, around 80 amps.

Where's the best place to connect the load?

Well, if you're going to do it at the Italian lab anyway, why not simply suck it out through CHAdeMO? This way it's quick and easy to test various cars without needing lifts and/or disassembly.

-Phil

 

[Herm]

Where's the best place to connect the load?

You should run a big fan across the battery when you do that..

 

[Volusiano]

I'd like to take one more stab at explaining the instrumentation hypothesis, without taking sides, because it seems to me that some people here don't "get" it, despite attempts by Phil and others to explain it. So, here are some hypothetical numbers, that are almost certainly not correct, but should make the concept clear:

Assume a new battery with 24kWh total capacity and an LBC (using Nissan's name for the battery controller) that limits charging to 22kWh maximum and 1kWh minimum. As users we would see a 21kWh capacity from "100%" to dead turtle.

Next, assume that at some time later the battery has degraded to 23kWh total capacity, but for some reason the LBC now sets the charging limit at 20kWh maximum and 2kWh minimum. This could be due either to a concern that the degraded battery needed more protection or to a programming error. Either way, as users we would now see an 18kWh capacity from "100%" to dead turtle.

All of our tests, whether Gids or wall kWh or range tests or dyno or whatever you can imagine, would show a capacity loss of 3/21 = 14%. In fact the true capacity loss would be 1/24 = 4%.

Ray

If the discrepancy of 10% here (4 vs 14) is due to a programming error (unlikely in my opinion because this would have been the first place for Nissan to look when the heat issue surfaced about a year ago) then Nissan would have jumped in to fix and provide a firmware update for the LBC months ago already, and everything would have been fine and dandy and we wouldn't have this discussion today.

If the 10% discrepancy is due to a concern that the degraded battery needs more protection, then it's still a legit reduction in range even though the 10% capacity is still there because Nissan shouldn't removed this protection anyway. In this case, it's still a lot of cause for concern. And if this kind of required protection is linear as more chemistry capacity is lost, then it'd be a huge cause for concern because the need for protection would be amplified further with more chemistry range loss.

At any rate, all this technical discussion about fixing any possible LBC error that might have contributed to artificial loss of range is fascinating, but it still shouldn't have any bearing or justification in Nissan providing an unacceptable 9 bar warranty. The whole purpose of an acceptable warranty for hot climate owners is to back up previous claims made by Nissan that hot climate owners should enjoy the same battery performance that cool climate owners enjoy. Simple as that.

If Nissan has an acceptable battery warranty in place, and later in due time manages to recover locked-up capacity by fixing their programming errors in the LBC or instrumentation accuracy or whatever, and the locked-up capacity is released back to affected owners and the chemistry capacity loss due to heat is insignificant like Phil thinks, then everything will turn out great and it's a win-win for everybody. Nissan gets to show that they have customer's back by issuing an acceptable warranty, affected owners get to reclaim and enjoy the range that they lost thanks to Nissan's software fixes.

The point I'm trying to make here is that I want to make a clear distinction between the PR problem that Nissan has FOR SURE right now versus any potential technical LBC problem or instrumentation that Nissan MAY have. And these two problems, while related, they simply don't mix.

If Nissan can't fix the technical problem(s) fast enough (hello, it's been at least 6 if not 9 months since the heat problem surfaced), then they NEED to proceed with underwriting an acceptable warranty NOW to fix their PR problem first. Then if they can manage to fix their technical in time before warranty claims start piling in, then that's great for them (as well as the owners).

This all goes back to one of Phil's earlier statement that said "Let's at least give them time to fix this before condemning them!" If we have no idea (and I assume Nissan has no idea either) how long it'll take Nissan to fix this technical problem, and it's been at least 6 if not 9 months already since the problem surfaced, and the problem is real and is severely affecting hot climate owners, then it's overdue by now for Nissan to put in a PR fix first if they need more time for their technical fix.

The thing is, their current 9 bar warranty PR fix is not acceptable because it doesn't solve anything for hot climate owners.

If anyone (Nissan or Phil) is convinced that a technical fix will solve this problem eventually, then there should be no concern to ask Nissan to underwrite an acceptable PR fix right now, because by the time technical fix becomes available, no warranty claim will be needed anyway in the future and Nissan will have a win-win situation in hand.

 

[cwerdna]

3) RE: Quick Charging - were you aware that no Nissan dealerships locally have a Quick Charger, but two Toyota and one Ford dealership in Phoenix metro have QC's? Why don't Nissan dealerships have QC's?

(Not to get too OT) I know one of the above dealers was mentioned before, but what's the reason that those two have QCs? Ford and Toyota don't even sell any cars w/a CHAdeMO port.

 

[JPWhite]

I'll say it AGAIN for clarity:

I'm not saying there isn't degradation in the battery, in fact, I'm sure there is some. I'm saying that it's possible that this is being amplified by flawed logic in the LBC, and that once this is fixed, many cars may not have as much actual loss as they presently appear to.

-Phil

I for one hope you are right in suspecting the LBC. One wonders why it has taken Nissan over 6 months of looking at the problem and still have no fix in affected vehciles for the LBC/instrumentation issue. I would think they would want to put this sordid event behind them asap.

 

[edatoakrun]

I'll say it AGAIN for clarity:

I'm not saying there isn't degradation in the battery, in fact, I'm sure there is some. I'm saying that it's possible that this is being amplified by flawed logic in the LBC, and that once this is fixed, many cars may not have as much actual loss as they presently appear to.

-Phil

When I mentioned LEAFSCAN Data earlier Phil, I wasn't referring to what it could tell you about the question you are discussing above, which I suggested should have been question # 1 (below) for the Jan 8 meeting.

I was referring to my question #2 below, on the question as to whether all LEAF energy use reports (capacity bar losses, gid counts, and kWh use reports ) are accurately reflecting actual kWh use of our LEAFs.

IOW, have you observed another distinct LEAF instrument error (possibly related to high temperature exposure) that is obscuring all our capacity observations, other than those that could be provided by the more accurate capacity test methods now being discussed on this thread?

I haven’t seen anyone suggest the the basic questions that must, IMO, precede all others on the subject of the battery capacity and warranty.

If these questions are left off of the official list, I hope someone at the meeting will be given (and take) the opportunity to ask them.

1) Is the proportion of the total LEAF battery capacity we can access between ”100%“ charge and the various low battery warnings constant, or does it vary significantly?

2) Are the kWh use reports from Carwings and available from the dash and navscreen as m/kWh subject to the same high level of error as the battery capacity bars and aftermarket SOC and ”gid” meters seem to be?

Without knowing the answers to these questions, LEAF owners and lessees would seem to have no way to independently determine whether our battery capacity is at the stated “70%” warranty level, or for that matter, at any other.

And if Nissan answers that our LEAFs' energy use reports are now commonly and significantly in error, ask:

3) When can we expect repairs to bring our LEAFs' energy use reports to at a reasonable level of accuracy?

http://www.mynissanleaf.com/viewtopic.php?f=4&t=11136&start=30" onclick="window.open(this.href);return false;

You may recall that my own range tests indicate that my own LEAF's instrument error seems to be predominantly due to #2 above, not an actual loss of capacity, but a kWh use reporting error. But my own LEAF simply does not yet have enough capacity loss to conclusively answer which instrument error (if any) could be causing the results described below:

...I chose a day with very close to the original temperature condition, and drove the exact same route over the first 87 miles of the trip, using the same mode (eco) and used my original trip logs to closely replicate the same elapsed times for each of the three (same distance) legs of the trip.

The results from 8/30/12 were:

97.3 miles to VLB, 98.9 miles in total, by the odometer.

CW: 96.5 (~2.5% under-report) total miles, at 5.7 m/kWh, 16.8 kWh used from 100% to about the same capacity level, slightly past VLBW.

Compare this test with my first test on 9/7/11:

91.5 miles to VLB, 93.4 in total, by the odometer

CW: 91.1 (~2.5% under-report) total miles, at 4.9 m/kWh, 18.7 kWh used from 100% to about the same capacity level, slightly past VLBW.

I do not believe that the slight increase in range over the last year reflects any increase in battery capacity. On the contrary, I expect that my total capacity ( though maybe not the amount of kWh that the BMS is allowing me to access) has declined by an undetermined amount, but it cannot be detected due to the “noise” of uncontrolled variables in a range test.

But I think the decrease of over 10% of reported kWh use, is simply too great to be consistent....

http://www.mynissanleaf.com/viewtopic.php?f=31&t=9064&start=20" onclick="window.open(this.href);return false;

 

[Pipcecil]

Now that we have had loads of data and plenty of discussion I think, looking at all of it, its probably fair to say that both sides are correct - and most likely correctly even with their problems: LBC software and heat degredation.

Remember the original Casa Grande test? The tested cars all came from nissan with ~85% capacity while they were all showing bars with reduced range to verify ~70%+ loss.

Think back to the range test. Some more variable results on a very controlled test. 2 bar loss cars getting more range than 1 bar loss cars, etc.

Also take a look at TickTocks's car. His gauge was "reset" although I wonder if they used a beta version of the LBC software. After many test, he concluded his car had only lost ~15% capacity as Nissan had reported vs. the ~30% from his capacity bars/range.

All this points to both a software (LBC) problem AND capacity loss too. It "almost" seems like the LBC is doubling the loss (like the previous example). In every instance it really appears this could be the case. So when 1 kWh is lost, it is reducing the lower and upper ends by 1 kWh on the battery.

Current as a hot texas car, while not as bad as arizona, I lost my second bar in July of this year (1 year 1 month ownership). Based on the old chart, I have ~79% capacity remaining. My range has reduced to reflect this approximate reduction as well (~20%+ loss in range). This would be way low on the curve, BUT if we pretend my capacity loss is only half (so ~89% at 1 year 1 month), I actually fit Nissan's curve - texas isn't as bad as arizona, so I should be above that, but well below the nominal curve - and I fit right there if I assume my loss has been doubled.

Now I am not an engineer, I am not a software guy nor am I an extreme loss phoenix car. BUT all this evidence seems to support both problems - and, it actually fits both scenarios and data quite nice.

 

[TonyWilliams]

Ok, that sounds logical. So, at 393.5 volts and 1C (24kW load), I should see about 60 amps, and as the voltage drops below 300 volts, around 80 amps.

Where's the best place to connect the load?

Well, if you're going to do it at the Italian lab anyway, why not simply suck it out through CHAdeMO? This way it's quick and easy to test various cars without needing lifts and/or disassembly.

-Phil

Not every car has a CHAdeMO port, but great idea.

 

[Desertstraw]

EPA Ranges
EV1 140
Leaf 73
Ford Focus 76

Isn't it strange that we are having erudite discussions about going from 73 miles to 50 miles twelve years later?

 

[TickTock]

I'll say it AGAIN for clarity:

I'm not saying there isn't degradation in the battery, in fact, I'm sure there is some. I'm saying that it's possible that this is being amplified by flawed logic in the LBC, and that once this is fixed, many cars may not have as much actual loss as they presently appear to.

-Phil

My data tends to support Phil's assessment. I do get a lot of variation in my measurements I cannot explain, but the best-fit curve of my wall power measurement is indicating noticeably less year-to-year loss then the capacity as determined by gids (100% gids*.08).

 

[Ingineer]

When I mentioned LEAFSCAN Data earlier Phil, I wasn't referring to what it could tell you about the question you are discussing above, which I suggested should have been question # 1 (below) for the Jan 8 meeting.

I was referring to my question #2 below, on the question as to whether all LEAF energy use reports (capacity bar losses, gid counts, and kWh use reports ) are accurately reflecting actual kWh use of our LEAFs.

IOW, have you observed another distinct LEAF instrument error (possibly related to high temperature exposure) that is obscuring all our capacity observations, other than those that could be provided by the more accurate capacity test methods now being discussed on this thread?

Since I personally have not carefully examined a heat-affected car, I cannot know, I can only speculate. The Leaf's LBC (Battery Controller) is responsible for all this information, and it uses 2 methods to calculate energy stored/used from the battery:

1. Coulomb counting: It uses a hall-effect current sensor to monitor total amps in and out of the pack. This is used to calculate SoC. The problem with this is that it's subject to offset errors and thus drift. It's also got a significant noise level, so this makes accurate measurement of small currents impossible and causes an overall error. This, in conjunction with #2 below, was deemed by Nissan engineering to be good enough for the task, and I agree with them as long as the software supporting all of this was done correctly. The other options would be much more expensive and suffer from their own deficiencies as well.

2: Resting Correction: Anytime the pack has been resting, such as when you first power up the Leaf from a period of time sitting, the voltage, temperature, and pack health are used to calculate the SoC. This is then applied as an adjustment to the SoC calculated in #1 above. This is why you can lose (or sometimes even gain) a bar after the Leaf has sit for awhile. Lab tests derived these numbers and they are usually very accurate, but they depend on proper software coding, and proper calculations. (Such as degradation factors)

LEAFSCAN™ can read all of this, but it is 100% dependent on the LBC for this information, just as all other instruments in the car are. If the LBC is indeed flawed, no numbers can be trusted.

-Phil

 

[Pipcecil]

EPA Ranges
EV1 140
Leaf 73
Ford Focus 76

Isn't it strange that we are having erudite discussions about going from 73 miles to 50 miles twelve years later?

Its not a simple apples-to-apples. The EPA test back then was SIGNIFICANTLY different than it is today. They did a huge recorrect that lowered many many MPG results. The first Honda Insight (the original) got 70ish MPG...yea....

Also, the EV1 was a very small car versus the larger Leaf and ford focus (EV1 was only a 2 seater), pack on a few pounds of extra safety features (air bags, etc.) and amenities (LCD screen, bluetooth, USB connection, etc.) and you can change the weight a bunch. Finally, you have to think about the cost - the EV1 was built from the ground up using all new components giving it an awesome drag coefficient. The Leaf, to be cost effective, had to use less desirable, but off the shelf equipment. The version of the EV1 would never had made it to full buy production - it was just too expensive.

I don't think it really is a good comparison. The best comparison we have is the range that people were getting - some as low as 40+ and some almost hitting 100 was standard (similar to the leaf but a little bit more than consistant and slightly less), it was never anywhere near 140.

 

[Ingineer]

Given the scope of this problem and the amount of lab work, testing, and software development that must be done, I don't think 6 months is unreasonable.

As a Leaf owner, I too would be not happy having to wait so long for a solution, but the unfortunate reality is that's sometimes how long it takes at a big multi-national automaker such as Nissan. If I was Nissan, I would have offered something in return for the hardships my customers were subjected to in the interim, and I would have done it up front as a gesture of good will.

I fault Nissan for not being more open and communicating this to their customers, but as far as the engineering side goes, the software alone can take many months to fix, test, and re-test. This is especially true if the R&D that developed the original was found to have errors, as they basically have to start over fresh and through out all the old assumptions. You can speed up some aspects with accelerated life tests, but ultimately these things must be tested for real and then they go back to the lab, make changes, then lather-rinse-repeat until they are sure they've got it right. They are especially likely to be even more thorough if they screwed it up the first time around. (read: slow)

-Phil

 

[surfingslovak]

I'm not a fan of Jack Rickard's bars and turtles rationalization of this issue, and I'm both surprised and disappointed that some of us would continue to paint it as a software issue alone with minimal battery degradation. This does not help to resolve it, and it does not help address the concerns some of the owners raised.

Based on the data from Casa Grande, it's safe to assume that many cars in Phoenix will see about 15% or more battery degradation after year and half. Any software and instrumentation problems will tend to compound this, and result in 20% to 30% perceived or effective loss of range, just like some owners have reported.

If this is not acknowledged and a software fix is not issues along with the new warranty, some owners might fear that they will see 40 to 50% perceived loss of autonomy before their battery is refreshed. I believe that this concern drove some of the complaints during and leading up to the Town Hall meeting. The discussion over the last few pages has done little to acknowledge this. I think we should focus less on the technicalities, and worry more about how to make this right by the affected owners.

 

[edatoakrun]

... have you observed another distinct LEAF instrument error (possibly related to high temperature exposure) that is obscuring all our capacity observations, other than those that could be provided by the more accurate capacity test methods now being discussed on this thread?

Since I personally have not carefully examined a heat-affected car, I cannot know, I can only speculate...

-Phil

I believe I've posted this about three times before, but would someone with a hot-climate "degraded" battery pack please allow Phil to take a look at it?

If you ever hook up the trailer and drive north of Sacramento Phil, I would love to have you Scan my LEAF.

I will probably won't be driving my LEAF south again myself for at least a few months (say a prayer for the Vacaville DC for me...).

My own speculation of why My LEAF might have relatively little real loss of capacity, and relatively large indicated loss of capacity, is that it could be related to its atypical climate experience, of peak temperature exposure not too far short of Phoenix, but average temperature exposure not much higher than Seattle.

 

[Volusiano]

I'm not a fan of Jack Rickard's bars and turtles rationalization of this issue, and I'm both surprised and disappointed that some of us would continue to paint it as a software issue alone with minimal battery degradation. This does not help to resolve it, and it does not help address the concerns some of the owners raised.

Based on the data from Casa Grande, it's safe to assume that many cars in Phoenix will see about 15% or more battery degradation after year and half. Any software and instrumentation problems will tend to compound this, and result in 20% to 30% perceived or effective loss of range, just like some owners have reported.

If this is not acknowledged and a software fix is not issues along with the new warranty, some owners might fear that they will see 40 to 50% perceived loss of autonomy before their battery is refreshed. I believe that this concern drove some of the complaints during and leading up to the Town Hall meeting. The discussion over the last few pages has done little to acknowledge this. I think we should focus less on the technicalities, and worry more about how to make this right by the affected owners.

+1. Amen!

Leafkabob said he just returned his car via a buyback yesterday and now he wondered if he did the right thing in light of Phil's technical opinion on this matter because everybody has great respect for Phil's technical savy on everything EV and LEAF related.

But the technical discussion we've been having over the last few pages, especially on the LBC's errors, is still pure conjecture so far in my opinion without any corroboration from Nissan, even if it's a great educated guess. If Nissan is already working on any kind of LBC correction/adjustment and is confident that the fix will mitigate the issue significantly, they would have issued some sort of announcement already, saying that they're working on a technical solution to fix the error and are confident the issue will be resolved. On top of that, if they realize that it will take them a bit longer to complete the fix, they still should have no trouble offering a reasonable PR fix (in terms of an acceptable warranty) to buy them time to complete the fix because once the fix is out, no warranty claim will be needed.

But they have said no such thing so far (6 months into it), and the unacceptable 9 bar warranty is evidence that they're not confident about any imminent technical solution at this point.

 

[JPWhite]

I'm not a fan of Jack Rickard's bars and turtles rationalization of this issue, and I'm both surprised and disappointed that some of us would continue to paint it as a software issue alone with minimal battery degradation. This does not help to resolve it, and it does not help address the concerns some of the owners raised.

"You live by the turtle and you die by the turtle".

I too was disappointed with Jack's rationalization that the real problem is due to faulty instruments/controllers.

However it does appear that the faulty software and instruments are masking/exaggerating the real problem at hand. There is little we can do to determine how much of the issue is instrumentation or battery, we're guessing. Nissan no doubt know a lot more after the Casa Grande investigations. As Phil points out (and so does Jack Ricard) Nissan should have handled the issue more transparently for the AZ owners. Instead the AZ owners are the unfortunate guinea pigs getting treated to mushroom management rather than "being tucked into bed at night".

Corporate harakiri using a blunt instrument indeed.

JP

 

[Ingineer]

Guys, please know that I have nothing more than theories at this point. I definitely don't want to dissuade anyone from changing their plans regarding buyback or whatever.

I want this to be fixed for the success of EV's in general, and of course I do want Nissan to succeed for the same reason.

I hope the Leaf can be successful in Phoenix, but despite my experience and knowledge, all I have at this point are educated guesses. I do hope everyone can be patient and give Nissan time to fix this one way or another, as I'm pretty confident they will.

However, If you are in a situation where your Leaf is no longer able to meet your current needs, then I advise you to bring this up with Nissan right now.

-Phil

 

[EdmondLeaf]

I just wish that battery capacity issue will be fixed by software update. No more restriction to park car in summer sun, no more AC in garage, and worry about 120F exposure.

 

[Stanton]

I just wish that battery capacity issue will be fixed by software update. No more restriction to park car in summer sun, no more AC in garage, and worry about 120F exposure.

This is another great misconception: regardless of what is/isn't wrong/fixed with the battery degradation, caution should still be used in hot climates. If we've learned ANYTHING from all the tests/meetings/analysis/conjecture over the last 6+ months, it's that things like excessive charging/driving in HOT (100+ degree, >6TB's, however you want to quantify it) weather should be avoided if/when possible. I believe that NOT "pushing" the car those few weeks a year (at least where I live) when it's excessively hot has/will help it in the long run. That doesn't mean it sits unused in my garage; that means I try to keep it cool when I charge at night in my garage, I don't "opportunity charge" during the day, and I make an effort to park in the shade.