Kevin Sharpe's decreased Roadster range

[scaesare]

Personally I think the posting of tweets and regurgitating of old forum topics is an unnecessary distraction and I will no longer respond to those here.

Wait. YOU suggested Twitter was a resource to get the full story.

Now, because the portion of the Twitter interaction referred to doesn't suit you, you decide it's unnecessary and inappropriate? Not to mention that you are posting info from HERE, to THERE... yet that's apparently OK?

I'm gonna say that, from this standpoint, your characterization of Bonnie's suggestion regarding the thread title as you described in on Twitter appears to be spin.

 

[dsm363]

Tesla battery range degredation forcing return to gas

And you aren't forced to return to gas, you have elected to do so. Don't you run a charging network? Couldn't you install whatever charge station you needed to get that 40 miles back in maybe 40 minutes?

 

[Kevin Sharpe]

In there is a subdirectory with a file named ahr.log. This contains the details for each brick, and can tell us if 8 is an outlier or not.

here's a link to that file in the last logs that we collected after the car was returned by Tesla... let me know if you need anything else;

https://www.dropbox.com/s/bxrfiq6tkdx10jp/201408200912_ahr.log?dl=0

 

[abasile]

Perhaps a warranty based on kWh cycled through the pack, with appropriate driver-visible instrumentation.

This, along with age, would be a more accurate (even if still rough) metric than mileage. On the other hand, for the purpose of effectively marketing EVs to folks who barely know what a kWh is, sticking with mileage seems preferable. And the warranted capacity level should be enough below the average expectation that Tesla isn't left with excessive warranty obligations.

It's not reasonable to compare a LEAF at 50,000 miles to a Roadster at 50,000 miles. The LEAF's usable battery capacity is somewhere around 40% of the Roadster's. Thus losing 20% of battery capacity at 50,000 miles in a LEAF is comparable to losing 20% in a Roadster at 125,000 miles.

In terms of cycling losses, I agree. Driving 50K miles should be harder on a LEAF battery. However, the premature degradation experienced by many 2011/2012 LEAF owners seems to be dominated by calendar losses that occur whether or not the car is driven. It's been more a function of battery temperature over time. Thus, some 2011/2012 LEAF owners in southern Arizona have qualified for the 66% capacity warranty with only half the miles driven compared to my car. This was an exceptionally bad situation until Nissan was essentially forced by a class action lawsuit to provide the aforementioned capacity warranty. By contrast, it seems that capacity loss has generally been much less of an issue with Tesla vehicles. And with Nissan's updated battery chemistry, hopefully virtually no new LEAF owners will lose enough capacity to qualify for warranty replacement.

Rather than a black and white warranty threshold, one thought would be for Tesla to offer each owner a pro-rated replacement discount on a new battery pack along the lines of how tire warranties work. The lower the capacity of the old pack relative to its age, the greater the discount on a new pack. Normal/average degradation would not be covered, exceptional degradation would be covered in full, and worse than average degradation would be partially covered.

 

[sethr]

Yesterday, Doug G mentioned that the cells used in our Roadsters are no longer manufactured. This made me wonder - are there cells being manufactured now that could be used to rehabilitate a Roadster battery? Or would the cells currently in production be unusable because they wouldn't match? What kind of supply of the original cells does Tesla have, and being old, what state are they in? I'm kinda wondering this because in all this heated discussion, no one has suggested that Tesla doesn't have the capability to restore Mr. Sharpe's battery? I'm not saying this is the case - I don't know enough. But perhaps someone else here does?

 

[breser]

Both ideal miles and rated miles are energy units, just more palatable to the average consumer than kWh. It would be nice if Tesla explicitly defined them in kWh.

I agree that they're more palatable to the average consumer. But I don't agree that they are energy units. We do not know what the algorithms that determine these values are. We know that these algorithms also have changed over time. On the Model S forum you'll see owners talking about regularly seeing no decrease in their range for the first several miles of driving. From what I understand Tesla has done an excellent job at making something that gives the average owner a good idea of how far they can go. But this does nothing for monitoring the health of your pack. You need values that are calculated on a consistent basis that doesn't change over time. Range mileage algorithms being under constant improvement does not meet that requirement.

This is especially true if we want Tesla to start warrantying range degradation in their warranty. They can't use those sorts of changing numbers in the warranty.

 

[JRP3]

I'm kinda wondering this because in all this heated discussion, no one has suggested that Tesla doesn't have the capability to restore Mr. Sharpe's battery?

Actually that was already suggested a while back.

 

[Doug_G]

Some TMC moderators have a history of moving posts and changing threads which I consider at best unhelpful and at worst a crude attempt to filter difficult information.

Kevin, it does appear that the thread title isn't really representative of the thread contents. If you would like to have it changed to something more accurately descriptive I will do that for you. Is there some title that you would prefer?

-mod

 

[djp]

here's a link to that file in the last logs that we collected after the car was returned by Tesla... let me know if you need anything else;

https://www.dropbox.com/s/bxrfiq6tkdx10jp/201408200912_ahr.log?dl=0

Thanks Kevin. Based on that log file, I'm not seeing any issues with brick 8, its SOC and voltage are in line with all other bricks. Your SOC is being limited by bricks 29 and 72, both of which are 0.02V below the rest of the pack. Bricks 45, 46, 73 and 74 are close behind and also lower than average. Based on this data it does look like the capacity loss is due to normal degradation, and not the result of brick 8 being an outlier.

 

[apacheguy]

Huh, well if all bricks are indeed aging evenly then that could perhaps put a different slant on things. After all, I was the one who suggested earlier in this thread that a warranty claim should only be pursued if certain bricks/sheets fell well out of line with the rest of the pack.

 

[scaesare]

Interesting indeed. Independent assessment that not only does there not appear to be any indication of fault, but that the degradation wound seem to be within expected norms that also happen to agree with Tesla's published guidance certainly is enlightening...

 

[woof]

...the degradation wound seem to be within expected norms that also happen to agree with Tesla's published guidance certainly is enlightening...

Enlightening indeed. And this is how this thread should end, not with a bang but with a whimper. Alas, it probably won't.

 

[AEdennis]

Tesla battery range degredation forcing return to gas

Enlightening indeed. And this is how this thread should end, not with a bang but with a whimper. Alas, it probably won't.

Guys. I think it doesn't really matter to most of us the specifics of Kevin's car or case. What should matter is that Tesla should specify with regard to the Model S and future batteries, Model X, Model 3, AND the purported 400 mile battery an actual expected degradation.

FURTHERMORE, I would like it if they would provide some warranty based upon that guideline for replacement under warranty AND a price list if the customer wishes to get a pack that is "newer" or refurbished to a higher capacity than their own AGED/DEGRADED battery pack.

The Battery Swap demonstration over a year ago took some of these thoughts into consideration over a year ago.

Though I bought into the hype of the Infinite Mile battery warranty for my S85, I am now questioning the disingenuous nature of that marketing and it's specific exclusions. However, as an owner, if they choose not to do something about it, I'm just stuck until my car's range is "unusable". Which in my case becomes the range of a BMW i3 BEV (i.e. A very long time).

Sadly, the topic for me remains as a request for Tesla to clarify and enhance the future battery warranty AND, if possible, the Roadster Warranty for e different classes (those that are original owners who may still be under a warranty and those of us who are under the CPO warranty, as well as those that are no longer warranted).

(ALL Caps because I can't figure out bold on this client)

 

[bonnie]

Guys. I think it doesn't really matter to most of us the specifics of Kevin's car or case. What should matter is that Tesla should specify with regard to the Model S and future batteries, Model X, Model 3, AND the purported 400 mole battery an actual expected degradation.

FURTHERMORE, I would like it if they would provide some warranty based upon that guideline for replacement under warranty AND a price list if the customer wishes to get a pack that is "newer" or refurbished to a higher capacity than their own AGED/DEGRADED battery pack.

The Battery Swap demonstration over a year ago took some of these thoughts into consideration over a year ago.

Though I bought into the hype of the Infinite Mile battery warranty for my S85, I am now questioning the disingenuous nature of that marketing and it's specific exclusions. However, as an owner, if they choose not to do something about it, I'm just stuck until my car's range is "unusable". Which in my case becomes the range of a BMW i3 BEV (i.e. A very long time).

Sadly, the topic for me remains as a request for Tesla to clarify and enhance the future battery warranty AND, if possible, the Roadster Warranty for e different classes (those that are original owners who may still be under a warranty and those of us who are under the CPO warranty, as well as those that are no longer warranted).

(ALL Caps because I can't figure out bold on this client)

I suggested updating the title to focus more on that, but the OP seemed to think I was trying to make the title more 'Tesla friendly' and preferred the title and topic stay exactly as it is. I think perhaps it would be better to start a new thread specifically discussing that and let this one die, hopefully.

 

[stopcrazypp]

Actually, Kevin's log data shows his pack's average brick Ah as well as the low brick Ah.

I noticed that a bit later on and did a comment on it and noted that a "normal" pack had a 1.56% below average:
http://www.teslamotorsclub.com/show...rcing-return-to-gas/page8?p=753146#post753146

Using the August 18th datapoint, brick #8 is 4.2% below the average. If a sheet swap raised the CAC to the current average, it will presumably raise Kevin's range from 199 to 208 Range Mode ideal miles. The relationship between CAC and range isn't exactly linear, but close enough for small perturbations.

It's possible that one bad brick lowers the pack average by keeping the pack from seeing the full capacity of the other bricks due to balancing constraints. We just don't know enough to be sure.

We don't know how it would raise the CAC because we don't have the ahr.log that tells the condition of each individual brick. In the worse case scenario where only the #8 brick is at 4.2% below average and every other 98 bricks are exactly at the average, then what you say is true (199 will raise to 208 range mode ideal miles). If other bricks are not at the average, then the effect from that particular brick is lower.

 

[wiztecy]

We don't know how it would raise the CAC because we don't have the ahr.log that tells the condition of each individual brick.

Kevin was nice enough to share it, you can download and review it from a link in post #183. This will give better insight on the health of the pack and what Tesla sees as well.

 

[Mitrovic]

You say, that company with 6000 employees and market cap of 35 billion is unable to defend itself against one man?

Beg you pardon? I do not say that. Other wise I would not tell they should go to court if they want!

But here on the forum, Tesla can not defend themselves.

- - - Updated - - -

Thanks Kevin. Based on that log file, I'm not seeing any issues with brick 8, its SOC and voltage are in line with all other bricks. Your SOC is being limited by bricks 29 and 72, both of which are 0.02V below the rest of the pack. Bricks 45, 46, 73 and 74 are close behind and also lower than average. Based on this data it does look like the capacity loss is due to normal degradation, and not the result of brick 8 being an outlier.

Yes, let it end end with this, there has been done enough of harm with it. Thank you djp.

 

[AEdennis]

... I think perhaps it would be better to start a new thread specifically discussing that and let this one die, hopefully.

I agreed and moved an updated version of my post to start a thread (called http://www.teslamotorsclub.com/show...rrent-and-future-battery-degradation-warranty) focused on the LACK of Battery Degradation clauses on ANY of the current Tesla Battery Warranties.

INCLUDING the much touted Model S "Infinite Mile" Warranty. (and let's not forget those of us who bought CPO Roadsters and told that the warranty was "better" than new at 37,000 mile and 37 months.)

So those that want to continue to discuss warranties solely and move away from Kevin specific posts, please update over there. Those that want to continue converations with Kevin, etc. post here.

- - - Updated - - -

Thanks Kevin. Based on that log file, I'm not seeing any issues with brick 8, its SOC and voltage are in line with all other bricks. Your SOC is being limited by bricks 29 and 72, both of which are 0.02V below the rest of the pack. Bricks 45, 46, 73 and 74 are close behind and also lower than average. Based on this data it does look like the capacity loss is due to normal degradation, and not the result of brick 8 being an outlier.

Pardon my ignorance djp, but I just want to know (since I had originally used all that I could find to see if the apparent loss of 15 miles of Ideal range on my wife's Roadster was real) what makes you an expert in this field? I was using the rudimentary explanation of earlier posts to look for LOW BRICK and make sure it changes for my "analysis" of my wife's car. And that's how I was convinced that the problem was brick 8 on Kevin's car.

Lucky for us, after the bleed test (which everyone said was useless) during our first annual for her Roadster 1.5 VIN 40, the Ideal miles went back up to 183 (after some stuff was reattached to the PEM, etc. Which had its own issues on our first day (which resulted in a replaced PEM))

 

[Kevin Sharpe]

Kevin, it does appear that the thread title isn't really representative of the thread contents. If you would like to have it changed to something more accurately descriptive I will do that for you. Is there some title that you would prefer?

We clearly have two topics intertwined here and I suggest we separate my Roadster issues from the wider degradation issues that impact all Tesla customers. I would like to keep this thread title and contents so that we do not destroy the flow of this thread (most split threads are a disaster IMO). I will then post the ongoing story of my Roadster here as it unfolds.

I then suggest you create a new thread in a forum that will be read by all existing and prospective Tesla customers to discuss the existing/new battery degradation warranty. I suggest you copy across any relevant posts from here and we try to keep this thread focused on my issues.

As I have said before, I'm not really interested in the Model S but it's clear that the battery degradation issue will be critical to Teslas future and is becoming a mainstream story. I've already seen copies of complaints to the Advertising Standards Authority in the UK and this issue will not go away.

- - - Updated - - -

Based on this data it does look like the capacity loss is due to normal degradation, and not the result of brick 8 being an outlier.

Thanks for taking the time to look at these.

It's certainly interesting although I have no idea what "normal" degradation means because Tesla won't tell us that.

We have requested logs from Tesla for the period prior to the work they undertook on my ESS in November 2011. I hope they will release that information without a fight :roll eyes:

Once we have the complete history we will get the logs analysed by an a ex-Tesla certified ESS engineer. Until then I'll focus on the reduction in ideal miles and it's impact on my driving.

 

[AEdennis]

...I then suggest you create a new thread in a forum that will be read by all existing and prospective Tesla customers to discuss the existing/new battery degradation warranty. I suggest you copy across any relevant posts from here and we try to keep this thread focused on my issues.....

Done (see previous post) - I created a thread at the Tesla Motors section (since this applies to the company as a whole for all models.)