Ugh. Another Model S fire - 2013-11-06

[SwedishAdvocate]

IMO we now have a problem that is 5% technical/safety related and 95% PR/image.

My wife, who likes our car but really doesn't care much otherwise said to me yesterday: "Did you hear that seven Teslas have caught on fire?"

I pressed her for details, but she wasn't even sure if she had been told or tead it somewhere. She just "knew". Boy oh boy...

Could you share how she feels about the car at this point in time after your talk?

 

[Johan]

Could you share how she feels about the car at this point in time after your talk?

Sure. So bascially I told her that No, it's three fires. One of them (#2) is a complete non-issue since it was a high speed accident with a driver crashing in to a tree then going through a concrete wall all while walking away relatively uninjured from it all! So that leaves accident #1 and #3, both similar with battery puncture from underneath. #1 made a lot worse by fire department doing the wrong thing drilling more holes in the battery.

The thing is with my wife I only that that much Tesla Time quota, since she's a bit tired of hearing me talking about the car and the company for the last few years. But after seeing the investment gains (no she doesn't yet know about the major drop in stock price since last week) and driving the car she's been a lot more interested

Anyway, the result after our talk is that she is not worried, she still believes it is a very safe car and she prefers to drive our two kids in the Tesla rather than our Volvo V70. But she does pay attention to the warning messages and knows that if the car tells her to pull over safely and exit the vehicle she better do just that.

 

[JRP3]

I'd also like to add if you look the Model S profile, you'll notice it doesn't have a front air dam that's lower than the undercarriage, so it's ground clearance measurement may be a bit different.

I think that should be changed so that the front air dam is the lowest point on the vehicle. Eliminating the lowest suspension setting would also be a good idea, and an easy software change, zero cost. Has there been any range comparison done between air and non air suspension cars? I'd expect the difference to be minimal.

 

[Gtoffo]

I still would really like to see pictures of the object the car collided with.....maybe it wasn't recovered?

 

[dsm363]

Well said Seesaw!

HOW CAN THIS MOST SIMPLE FUNDAMENTAL BASIC SHORTCOMING of my air-suspension "S" CONTINUE to be overlooked by Tesla!?!? I continue to be outraged that I can not "lock" my ride height at 6.6" (the same height as a non-air) so that I am NOT "the freeway debris plow" at 5.21" of ground clearance!! How can my P85 be so indescribably fabulous yet have such simple correctable shortcomings that are not being addressed?

Outraged? I'm sure it is something they are looking into but there are other cars that sit even lower that the low setting on the Model S as well. Unless one can always predict the height of the object in the road there will always be an 'unsafe' height at which the Model S hitting something might cause a similar issue. If this is accurate, the 2011 M5 has a ground clearance of 4.6"
BMW M5 (F10) 4.4 V8 7AT (560 HP) - 2011, 2012, 2013

 

[EdA]

I don't see the issue. It's a sports car; sports cars are low. The Model S is definitely not the lowest around town. Some quick google results on stock ground clearance: (not sure if all are 100% accurate or measured to the air dam or what)

Prius is 5.5"
Volt is 3.7"
Porsche 928 is 4.5"
'14 C7 Z51 is 3.25"
BRZ 4.9"
etc.

The reality of the situation is that road debris is not a uniform size. Yes, the Model S is low, especially with the air suspension at freeway speeds, but there are enough other vehicles on the road with low ground clearances that they should experience damage from debris as well. Even if you boosted your Tesla up to 7" of ground clearance, if you hit a tall metal piece in the road, it's going to have the same effect either way.

I think we'll just have to get used to the "car bqq" jokes. The current situation is that if you run over something serious on the road, your Tesla may catch on fire and burn down. In all my years of driving, I've never personally heard of or seen a gas-powered car running something over and catching on fire. I'm sure the statistics say otherwise, but I have yet to hear somebody say "I ran over a big piece of metal on the highway and my car ignited and got totaled!" It is apparently a risk of driving a Tesla. It is also good to know that the safety systems continued to work and that everyone got out okay. I'd still rather take a Tesla than any other car on the road in light of the recent events.

I have a friend who's car ran over a mattress, after dragging it for a while they were urged to pull over by other drivers and the whole car went up into a crsip.

 

[Gtoffo]

Outraged? I'm sure it is something they are looking into but there are other cars that sit even lower that the low setting on the Model S as well. Unless one can always predict the height of the object in the road there will always be an 'unsafe' height at which the Model S hitting something might cause a similar issue. If this is accurate, the 2011 M5 has a ground clearance of 4.6"
BMW M5 (F10) 4.4 V8 7AT (560 HP) - 2011, 2012, 2013

What if LOWERING the car's height actually IMPROVED its safety? Objects would collide with the front causing only cosmetic/superficial damage instead of being able to slide underneath the car and puncture the battery.

 

[jerry33]

HOW CAN THIS MOST SIMPLE FUNDAMENTAL BASIC SHORTCOMING of my air-suspension "S" CONTINUE to be overlooked by Tesla!?!? I continue to be outraged that I can not "lock" my ride height at 6.6" (the same height as a non-air) so that I am NOT "the freeway debris plow" at 5.21" of ground clearance!! How can my P85 be so indescribably fabulous yet have such simple correctable shortcomings that are not being addressed?

You're kidding, right? The first one really appeared to be a fluke. With the second one, no amount of ground clearance would have helped, and the third one happened four days ago, and is really just bad luck. You really expect a software revision in four days? And that's if this is a shortcoming. I'm not convinced because two isn't a significant number.

I suspect that driving no faster than the speed limit and keeping a safe distance (3-4 seconds) behind the other vehicle would have done more to prevent these accidents than anything Tesla will be able to do short of encasing the Model S in depleted uranium tank armour. My opinion is that there is no ride height that would be safe from every possible piece of road debris.

 

[Mario Kadastik]

One solution, though something that would need to be tested if that hampers breaking distance, would be for the car to automatically increase air suspension hight in case of emergency breaking. So if you hit the breaks hard the car also rises as fast as it can to possibly avoid getting damaged.

 

[SwedishAdvocate]

Well said Seesaw!

HOW CAN THIS MOST SIMPLE FUNDAMENTAL BASIC SHORTCOMING of my air-suspension "S" CONTINUE to be overlooked by Tesla!?!? I continue to be outraged that I can not "lock" my ride height at 6.6" (the same height as a non-air) so that I am NOT "the freeway debris plow" at 5.21" of ground clearance!! How can my P85 be so indescribably fabulous yet have such simple correctable shortcomings that are not being addressed?

You're kidding, right? The first one really appeared to be a fluke. With the second one, no amount of ground clearance would have helped, and the third one happened four days ago, and is really just bad luck. You really expect a software revision in four days? And that's if this is a shortcoming. I'm not convinced because two isn't a significant number.

I suspect that driving no faster than the speed limit and keeping a safe distance (3-4 seconds) behind the other vehicle would have done more to prevent these accidents than anything Tesla will be able to do short of encasing the Model S in depleted uranium tank armour. My opinion is that there is no ride height that would be safe from every possible piece of road debris.

One solution, though something that would need to be tested if that hampers breaking distance, would be for the car to automatically increase air suspension hight in case of emergency breaking. So if you hit the breaks hard the car also rises as fast as it can to possibly avoid getting damaged.

I’m guessing it also might comprise the various automated driving aids that exist to further improve handling if the car is pushed to it’s limits (such as a high speed evasive maneuver, or during icy winter driving conditions).

At high speed maybe these systems need a different calibration if the car is travelling with a higher ride height then what is currently the default setting.

I’m guessing these calibrations can be implemented to allow for a higher ride height. But I’m further guessing that it might take some time for Tesla to implement this on the Model S. A project such as this one will probably demand engineering resources that are currently allocated to other projects (and here I’m guessing the Model X).

 

[scottf200]

My wife, who likes our car but really doesn't care much otherwise said to me yesterday: "Did you hear that seven Teslas have caught on fire?"
I pressed her for details, but she wasn't even sure if she had been told or tead it somewhere. She just "knew". Boy oh boy...

I'm planning on a Model X (still of course) and called my insurance company for a quote on a Model S (MetPay). It wasn't in their system and after the underwriter spent time trying to locate info the supervisor overrode and said they could insure me but the numbers would be based on the cost of the car.

Anyway during the conversation the lady I was talking to had gone to the website to check on the car and the price. I asked what price they were going to use and she said she saw quite a range and would use what I wanted.

A couple things was she was very friendly (after this whole 10+ minute talk/wait/hold/talk situation and mentioned something about drooling when she brought up the site.

To my final point ... she said she heard about 5/five Tesla car fire recently!!! I briefly explained and she was fully understood then it was not an unusual situation in that this electric car was any more dangerous.

$448 for 6 months to answer the linger question.

 

[Alpha]

One solution, though something that would need to be tested if that hampers breaking distance, would be for the car to automatically increase air suspension hight in case of emergency breaking. So if you hit the breaks hard the car also rises as fast as it can to possibly avoid getting damaged.

I don't think the air suspension (at least in it's current hardware incarnation) adjusts nearly fast enough for this to work. It sure seems like I have to wait forever to get it to adjust an inch or two for a steep driveway.

Good idea though.

 

[JRP3]

Seems as if it would create a stability issue if braking and turning hard, maybe not enough to matter.

 

[vgrinshpun]

Adding automatic fire suppression system to the battery pack might be another solution to the potential fire problem. It will improve safety of people in the car no regardless the shape/size of the road debris, while the cost and additional weight gain would be very reasonable.

 

[ABVA]

There is a car fire every 96 seconds in the US. Some with fatalities or severe injuries. We had only three, every time driver walked away unscathed. Please let us not make a "Mountain out of a Mole":

National Vehicle Fire Statistics | Chandler Law Group

 

[JRP3]

Again, what happens with other vehicles is irrelevant, perception has already made this a mountain.

 

[omgwtfbyobbq]

I agree, but I'm quite sure that if there is another fire after NHTSA signs off on it they will indeed investigate once again and probably force changes and/or a recall.

I don't think it's the Cobalt as much as the Oxide, O2, which means the cell supplies it's own oxygen when burning. [/COLOR]


All current lithium cells use a flammable electrolyte, including the A123 cells in the SparkEV. However those don't contain O2. On the other hand they are a higher C rate cell so if shorted they can put out much higher currents, which could lead to something else catching on fire. I don't think the BMS in the Tesla does anything to isolate a module during a fire, it's the physical pack construction which accomplishes that.

That makes sense. I've seen some test with TS/CALB where they've shorted cells and there wasn't enough energy to ignite the case, but those how much higher internal resistance than A123 cells. Apparently the A123 cells behave in a similar fashion, just quicker because of lower internal resistance.

https://www.youtube.com/watch?v=rb_J2QQ0k-4

https://www.youtube.com/watch?v=lWk24MbYEBg

In contrast to the Panasonic NCR cells, that, like you mentioned with most cells that have O2 in the cathode, and will react to internal shorts by releasing a lot more energy/heat.

https://batteryworkshop.msfc.nasa.gov/presentations/Perf_Safe_Test_Panasonic_Li-Ion_NCR_18650_Cells_JRead.pdf

I was under the impression that the Tesla BMS would try to actively manage the module cooling until it became clear that it had run-away, and which point it would stop circulating coolant to isolate the modules, but I guess not it. It may not make a difference.

 

[SwedishAdvocate]

Again, what happens with other vehicles is irrelevant, perception has already made this a mountain.

Wasn’t that also the case after the first fire?

It seems that was pretty easily fixed with a blog post on the Tesla website and a couple of media appearances by Elon.

As I understand it Apple also faced a perception-problem with the Iphone 4 ”antenna-gate”. Enter Steve Jobs:

Steve Jobs at the Antennagate Press Conference (2010) - YouTube

And as I understand it the Iphone 4 sales were just fine (spent 2 mins. searching for some numbers, but couldn’t find any…)

Are we really sure this perception problem is unfixable?

- - - Updated - - -

There was also a Q&A with Jobs, Cook & Mansfield after the presentation that I link to above, but I can’t find a good video of that one…

 

[Raffy.Roma]

Are we really sure this perception problem is unfixable?

It can be more difficult to work out a perception problem rather than a technical problem. Maybe that a celebrity could help to work out a perception problem.

 

[Cottonwood]

There is a car fire every 96 seconds in the US. Some with fatalities or severe injuries. We had only three, every time driver walked away unscathed. Please let us not make a "Mountain out of a Mole":

National Vehicle Fire Statistics | Chandler Law Group

I replied to this reference on another thread. Here is a repeat of that reply.

Nice reference. Let's take a stab at scaling that to Teslas. I will use a rough number of Teslas on the road as 20,000 (Roadsters and Model S's). From Passenger vehicles in the United States - Wikipedia it looks like there are about 250 million automobiles in the U.S.

If Teslas had fires at the same rate as all automobiles, then the average time between Tesla fires should be:

96 seconds x 250,000,000 / 20,000 = 1,200,000 seconds or 13.88 days​

It seems like we are having Tesla fires at a rate of less than 2 per month...That would mean that the rate of Tesla fires is less than the average automobile. Please remember that even though we can calculate average rates, they probably have a Poisson distribution, which has a lot of variance. As some would say, "Its not one fire every 14 days, its a 1/14 chance of a fire each day."

Does this make sense?