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Slideshow: 'Bizarre' Incident Led to Tesla Battery Fire

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Elizabeth M
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Good to know
Elizabeth M   10/8/2013 7:09:41 AM
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Thanks for your continued excellent coverage of this, Chuck. It's good to know that it was a bizarre and rare incident that led to this fire, and that it wasn't some major defect in the battery. Still, these incidents are troublesome and I hope any issues that could potentially cause them are resolved by engineers before something like this happens again.

Pubudu
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Re: Good to know
Pubudu   10/12/2013 3:43:03 AM
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True Elizabeth, this should address immediately by the engineers cause that there are many EVs on the roads, so action should take immediately and users should educate on this issue.  

Rob Spiegel
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Video
Rob Spiegel   10/8/2013 8:37:23 AM
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Chuck, and can see a number or reasons that video went viral. It feeds the concern that EVs can be dangerous. There must have been some delay before the fire that allowed the driver to escape.

Jennifer Campbell
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Re: Video
Jennifer Campbell   10/8/2013 10:16:54 AM
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I've read other reports that said the car is designed so well that the fire was contained to the front, and didn't immediatly engulf the cabin. I'm glad to hear that the driver escaped unscathed, but it can't be a very good feeling to watch your Telsa go up in flames!

Rob Spiegel
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Re: Video
Rob Spiegel   10/8/2013 10:27:31 AM
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Yes Jenn, in the video it was clear that only the front engine compartment was on fire. What's unfortunate about this incident is that it's so unusual it really can't be fixed through engineering. It ends up adding -- probably unfairly -- to the perception that EVs are not safe. I thought the conversation between the two guys taking the video was perfect. Thanks for not cutting the audio.

Nancy Golden
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Re: Video
Nancy Golden   10/8/2013 12:44:21 PM
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Failure analysis is bringing new information to light that seems to work in favor of the Tesla - especially since the passenger compartment did as well as it did considering the massive fire inches away. However - perception is everything and regardless of the facts that are being unearthed after careful investigation - this incident has defintely caused further damage to the already fragile reputation of EVs.

Rob Spiegel
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Re: Video
Rob Spiegel   10/8/2013 1:08:11 PM
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Nancy, I agree about perception is everything. Most will look at this and think, "Ah, another EV up in flames." Especially since this video has gone viral. With 3 million page views, the video of the accident is getting some attention. Tesla's stock fell 6.2% on the news.

ChuckCooper
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Re: Video
ChuckCooper   10/8/2013 1:39:27 PM
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Actaully, it's pretty impressive that the fire was so well contained.  In many car fires with leaking gas tanks, the gas follows the slope of the road and ends up surrounding the car forcing the occupants to open the door into the fire and then escape through the flames.  Thinking about burning gas on my feet while breathing flames make me appreciate the Tesla's containment.

Rob Spiegel
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Re: Video
Rob Spiegel   10/8/2013 1:45:52 PM
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Good point, Chuck. Without a leaking, burning fluid, the EV fires are less dangerous. It's still a rough image for consumers to see, especially as this video goes viral. While an engineer may marvel at the containment, most just see a car engulfed in flames.

Tool_maker
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Re: Video
Tool_maker   10/12/2013 1:45:55 PM
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@Nancy: I agree about the perception issue, but that is not a new phenomena. I remember how Ralph Nader was able to successfully kill the Chevy Corvair because he claimed they were a rollover hazzard. Both my brother and I drove Corvairs without a hint of problem and were surprised by Nader's tirade in front of Congress about the Corvair's propensity to turn over. I did not believe it then and I do not believe it now, but public perception was that the cars were accidents waiting to happen. Adios Corvair

 

Charles Murray
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Re: Video
Charles Murray   10/8/2013 6:16:37 PM
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I agree, Rob. The video does feed concerns over lithium-ion safety. I admit that I, too, believe lithium-ion can be dangerous -- if it's not engineered properly. But if it is engineered properly, there should be no reason for concern, just as there's no reason for concern when I climb into a gasoline-burning car.

Rob Spiegel
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Re: Video
Rob Spiegel   10/8/2013 7:36:34 PM
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Good point, Chuck. But perception is everything. The YouTube video has been getting plenty of hits, which led to Tesla's stock going down more than 6 percent. We're not going to see videos of gas cars going viral.

etmax
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Re: Video
etmax   10/9/2013 9:00:53 AM
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Chuck, thanks for providing the followup. It's really good to know that it was a particularly severe incident that would have caused issues no matter what the technology. Imagine in a hydrogen car!!

tekochip
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Re: Video
tekochip   10/9/2013 11:19:15 AM
Charles;
 
You may remember that here in Chicago, back in `94,  a minivan burst into flames after it ran over a taillight assembly that had fallen from a truck.  The fire killed six children and might have been forgotten if it wasn't that the ensuing investigation brought down Illinois governor Ryan.  I think the Tesla incident is a rather similar, in that the road debris damaged the fuel system and caused it to ignite.  There's a lot of stored energy in any kind of vehicle, and you never want it all to be released at once.
 
No just a problem for automobiles, since road debris also damaged the fuel system in Concorde flight 4590 and caused the aircraft to crash.


Pubudu
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Re: Video
Pubudu   10/12/2013 3:35:41 AM
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 True Rob this video went viral; mainly who will have a negative perception towards EVs will do the ground work.th was a great plus point for them to justify their believes. 

tekochip
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Gasoline
tekochip   10/8/2013 1:06:20 PM
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A fuel tank full of gasoline would not have faired any better.

RogueMoon
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the caged demon of stored energy
RogueMoon   10/9/2013 8:55:23 AM
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I must agree with tekochip.  The hazards of gasoline are not trivial either.  20th century car designers had their troubles too.  Anytime you bottle up a large amount of energy in a tight space, you have risk to life and limb.  As energy density in batteries increase, this concern will only increase with it.  Safety in a passenger automobile will always be a primary consideration to the designer..  

RICKZ28
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Re: the caged demon of stored energy
RICKZ28   10/9/2013 1:27:37 PM
I think the jury is still out on this subject.

Over the years, I've seen countless "ICE" cars and trucks severely damaged in crashes, and many torn into pieces (frequently fatal), but very few resulted in fire.  I remember seeing a number of Ford Pintos badly damaged from being rear-ended (back in the old days), not one fire.  The most car fires I've seen were old VW buses and bugs on the side of the road, not from a wreck.  

Let's see how the electric cars perform after many more severe crashes occur.  Will every electric car catch fire when the batteries are punctured or otherwise damaged?  What happens to people when they're exposed to or covered with battery stuff?  I don't know, but actual bad crashes are the best way to determine what happens, and real-world results are better than crash test results or FEM/FEA.

CuriousEngineer
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How fast the car was going at the time of the accident?
CuriousEngineer   10/9/2013 8:53:46 AM
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I think theoretically it may possible (although probably impactical) to design the thicker plate on the bottom of the car if the speed is taken into account.  I am not a mechanical engineer, but is it possible to calculate the maximum force of the object hitting the bottom of the car if it is moving at the fastest speed (say 80 mph on the highway)?

TOP
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Hardly possible to anticipate
TOP   10/9/2013 8:56:33 AM
I recall some years ago an incident in which a piece of rebar was thrown up into the underbelly of a conventional car impaling the driver. This happened on one of the bridges in the Bay area. The authorities were at a loss as to why the woman was dead until they tried to remove her from the car.

I have experienced damage to fuel tanks during my many years of driving. It happens. I have hit dunnage that has fallen off of trucks. Truck tires that have come apart are another real hazard frequently found.

The real culprit is not the battery, but the fact that truckers can get away with dropping objects off their trucks that can cause this sort of thing. Whether it is pieces of metal, stones and rocks, dunnage, bungee straps or you name it this is a very real hazard that long predates electric cars.


I have passed by gasoline fires while living in Chicago. They usually happened when an ill maintained fuel system leaked pressurized gasoline in the engine comparment while in stop and go freeway traffic. And yes, gasoline will cause the "Hey dude, I can feel the heat." reaction. Take a trip to the bone yard and see how many cars have been damaged by gasoline fires.

Battar
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Concorde
Battar   10/9/2013 8:56:55 AM
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This is the same scenario that brought down the Air-France Concorde in 2004 - bit of metal on runway, thrown up by wheels, pierced fuel tank, etc...

j-allen
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Tesla fire
j-allen   10/9/2013 9:05:44 AM
We cannot engineer on the basis of freak incidents.  The excess coverage given this event reminds me of news stories wherein prejudiced writers sieze upon any misdeed committed by people in the hated population group.

As a cunter story a local woman crashed a gasoline car.  The resulting fire burned her to death.  So, should we condiser gas cars intrinsically unsafe? 

Chuck_IAG
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Re: Tesla fire
Chuck_IAG   10/9/2013 9:53:31 AM
@j-allen:  "So, should we condiser gas cars intrinsically unsafe?"  No, we should consider women drivers unsafe.  (Joke, ladies, sheath the claws)

Tesla will need to ride through this just like Ford did with the Pinto. As I watched the story unfold at the time, engineers were generally saying, "yes, a rear-end collision might cause a gas tank to explode, given the right combination of events, but it's not likely enough to redesign everything about the car (or cars in general) or abandon the design entirely."  So Ford did both anyway- they re-engineered the tank in a number of ways and soon abandoned the model line as well. 

I even made a joke about it at the time: the Pinto table lighter- press on the trunk and the whole thing bursts into flames.

Tesla is playing in the big leagues now.  They have to ride the wave like everyone else.  Toyota and Volvo with sudden acceleration, SUV rollover hazard, Corvair with everything, and so on.

John
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ev faired better than gas car
John   10/9/2013 9:25:46 AM
Mr. Musk doesnt saying anything about the rubber bladder that most new gas cars have these days to reduce the chances of leaking if the metal tank is punctured.  I wounder how it would fair with a 25 ton force.  What's bizzar is running over a piece of flatened copper tubing to have it poke a hole in the side wall of a good tire.  What's just wrong is 25 tons of force punching 1/4" plating.  How fast was the guy driving; was he texting?  Atleast nobody was hurt.

skipperj
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Concerning the "debris"
skipperj   10/9/2013 9:26:42 AM
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Thru the years I've logged 1.5 million miles in a semi-truck.I've seen a lot of "things" fall off mine and other trucks.The only thing I can figure it was a piece of broken spring leaf from the suspension.Or maybe a piece of a broken brake drum.The spring leaf when broken ressembles a sling blade with a curve in it and a sharp edge on the end that could easily puncture tires,fuel tanks,oil pans,etc.Most of the springs have a wrap around band that is supposed to keep the leaf from coming out,but I've seen a lot of them missing.If the spring breaks completely off there's no band wrap that can prevent it from falling off and into the road.Hope this doesn't scare anyone,cause this is a rare occurence these days with air suspensions phasing out the leaf type spring.I'm curious as to what really punctured that hole in the battery box.Won't know till the NTSB gets back to work!

TunaFish#5
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Re: Video
TunaFish#5   10/9/2013 9:37:26 AM
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@ Bill the Architect:

So what is "ICE" anyway.  "In Case of Emergency" comes to mind, but I'd rather you answer than I google.  Thanks.

TunaFish#5
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Lame Slideshow; engaging comments
TunaFish#5   10/9/2013 9:41:43 AM
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Except for the 1st photo, I found this slideshow lame.  (The article was quite good.)  Just my 2¢ for the staff.

The attached conversation is engaging, however, so I guess the publisher is getting the eyeballs they need.

TunaFish#5
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Re: Video
TunaFish#5   10/9/2013 9:59:45 AM
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@BtA:

OK -- I got stuck relating "ICE" as an architectural euphemism for "bizarre incident."

AREV
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Hot Telsa
AREV   10/9/2013 10:16:45 AM
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As a manufacturer we design daily for the impossible to happen. Fool poofing to its maxium. We have installers to install the product and we still see amazing results. A car can be driven by anyone, anywhere in all conditions. IE every oddity will be experianced. We protect our employees for any accident that has ever happened, etc. The first article I read on this fire stated that the object that caused the damage was not located. This indicates that all arguements are suppositions. Show is the objet if one was found. On gas cars the gas line that I am aware of is app 3/8" wide.Tto hit is is satistically small.Typically it is routed in stong areas.  The battery of the Telsa is the entire bottom of the car. Statistically speaking one fire of a Telsa I assume is much higher than experianced on gas cars. IE millions of gas cars vs handful of Telsas. Also the fire story stated that the fire crew removed part of the front end to access the fire. Did they check for stray voltage at that time. Fire men will start carrying VOM meters. As a manufacturer of sheet metal devices I would not buy a 25 ton press to put a 3" hole in 1/4" steel. Way to small. What's going to happen when JC Whittney starts making modifications for EVs for speed, looks (leds under the car . . . .)? What is going to happen when high school kids start driving 10 year old EVs?  Saying all this, I am an advocate for EVs - cut the bull and design them so they are afordable, reliable, safe, and fit their own unique application.  More engineering guys. Fine tune the application, take buckets of cash to the bank.

Anonymous
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Re: Video
Anonymous   10/9/2013 11:12:13 AM
I think you are giving far too much credit to a GM vehicle that has not been in this particular accident.  I highly doubt that if a sharp metal object managed to pierce the fuel tank of the Volt (because really, the battery pack is the fuel tank, and it was pierced) with that same piece of metal dragging and creating sparks, that the Volt would also not go up in flames.  

What kind of protection is surrounding both fuel tanks (Battery and Gas) in the Volt? I know that my ICE vehicles at best only have a thin piece of metal no better than the 1/4" plate armor the Tesla has, at worst, they are completely exposed plastic gas tanks hanging down!

Lastly, lets consider that perhaps that thick armor AND the thick battery stopped the piece of metal from actually injuring the passenger in the Tesla.  The thin floorboards of my ICE vehicles wouldn't have stood a chance!

 

On another note, why is it that we see millions of gasoline burning cars blow up in extravagent ways in almost every Hollywood movie you see, but nobody thinks they are driving around a bomb? (I know that Hollywood is not accurately representing gasoline cars when they explode, but is that common knowledge?)

Cadman-LT
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Re: Video
Cadman-LT   10/9/2013 1:07:26 PM
I don't agree with it being an excuse, it's a fact. I mean gasoline cars are way more likely to catch fire than an electric one. I've had a van burn to the ground before, my buddy has had 2 cars, yes 2 burn in the same night. So gasoline cars are actually worse.....you just don't hear about them like you do the tesla incident. It was a one time freaky thing, get over it.

Cadman-LT
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Re: Video
Cadman-LT   10/9/2013 1:11:57 PM
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By the way, do you have 1/4" armor protecting the bottom of your car? I think not. fuel lines etc.....hmmmm one errant rock could do it

Shadetree Engineer
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Redesign the battery, not the car
Shadetree Engineer   10/9/2013 1:41:18 PM
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I think it's a bit untrue that redesigning this car means the same as designing for unecessarily bizarre events. To change the battery to something that is in a safer location and/or in a smaller package that is less likely to be damaged means a drastic reduction in range. I doubt that line of research will happen for this car, but what can be done to reduce secondary heating from any sort of battery puncture? Starting with this incident, I would like to know just how much of the 'flammable electrolyte' can potentially leak out of this battery pack? In a worst case scenario if it can drain out to a maximum potential, are we talking a gallon of flammable liquid? Or 20 gallons? Or is it just some technical amount like a handful? I would expect this electrolyte to be unable to leak out very fast, so I would also expect a puncture to consist of a flame source that lasts for a long period of time. Long enough that I would expect the major concern is the ability to set other structures around the battery on fire given enough time. I think it might be a reasonable bit of engineering research to see if there is something that can be done in the way of placing a thin sheet under the bottom of the battery pack, or perhaps totally surrounding it, that when in contact with the electrolyte, and/or when heated from a battery fire - will act to suppress further burning by producing a vapor that displaces oxygen, by expanding to seal gaps & possibly close a puncture and maybe to absorb heat. I would also think some kind of thermally-acting fusible links can be placed in between individual cells. Building these qualities into the batteries internal structure is not likely, but the battery housing could certainly be redesigned. Is anyone asking Elon Musk about a battery that can be designed to kill itself more gracefully? I will think first that his number one priority is to avoid any increase in production costs, even if they involve a small increase that results in great reductions of potential harm.

CharlesM
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More of these kind, please
CharlesM   10/9/2013 1:48:19 PM
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Thanks for a useful blog post, Mr. Murray. Informative and non-sensationalistic.

Hal B
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Time to rethink?
Hal B   10/9/2013 1:54:24 PM
[quote]The question is with respect to EV's would you want that much surface area subjected to road debris and abrasion.

GM didn't.[/quote]

I understand why the entire underside of the vehicle is the battery but does anybody now think that's a good idea?

-Hal

Ockham
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"one errant rock" puncture a fuel line
Ockham   10/9/2013 1:58:41 PM
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"one errant rock puncturing a fuel line".

This statement is absolute rubbish. First of all, steel fuel lines are pretty robust pieces. Secondly, they are generally routed in areas where such secondary impacts are mitigated or made impossible. Thirdly, a 5/16 or perhaps 3/8" fuel line is a tiny target. Fourthly, even if a statistical miracle occurs, and something punches a ding in a steel line which results in a crack and a leak, it is going to be a tiny puncture. Such a puncture is generally not going to result in a massive and uncontrollable fire.

Even cracked and leaking rubber lines which were common on suction type fuel systems in the 1960's and 70's (before the general adoption of EFI systems) RARELY resulted in massive uncontrollable fires. I've driven such designs for forty years, including a number with 30+ year old rubber that practically fell apart in my hands when I finally replaced it. NEVER ONCE have I had, seen, or even heard of a fire caused by "rocks puncturing a fuel line", etc. In a gasoline car, if the fuel line is disrupted, the engine stops. When the engine stops the fuel stops flowing, because it is SUCTIONED out of the tank, (or pumped out from an internal fuel pump on EFI designs) Either way, it stops, the source of the fire's energy disappears and the fire either goes out or is easily put out.


Contrast that with a runaway lithium/electrolyte fire in multi-hundred pound chunk of battery. You're not going to put that out with a dry chemical fire exstinguisher!


So, thanks but no thanks on that big lithium ion battery chunk ten inches underneath my family jewels.

I'll take my chances with a fuel system design that has successfully functioned for decades, producing only a very miniscule fraction of a percentage of fuel system fire accidents resulting in significant loss of property/death per million miles travelled.

Tesla is by far the coolest and best hope for the electric car...but you're kidding yourself if you think it is error free and in every way already better designed than a mature technology like the ICE automobile.

 

timbalionguy
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Unanticipated incident
timbalionguy   10/9/2013 2:17:54 PM
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This incident reminds me of the one and only Concorde aircraft crash, caused by a piece of debrie on the runway bouncing up and puncturing a fuel tank in the wing. This happened late in the service life of this aircraft. Accidents of this type with aircraft are really uncommon, especially ones with a disasterous ending.

Road debris damaging the underside of vehicles is not uncommon, and sometimes we see small, seemingly harmless objects that do big damage. The (I think) flat area on the bottom of the Tesla helps by providing a surface for objects to bounce off of, but no system is entirely foolproof. I think efforts need to be made to design batteries that don't burn and require less aromr, rather then using thick, heavy armor. Or, maybe a kevlar or carbon fiber plate below the battery pan would help mitigate such events without adding too much weight.

If I could afford one, I would own a Tesla in a heartbeat!

curious_device
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Re: Unanticipated incident
curious_device   10/9/2013 2:25:27 PM
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Kevlar and woven carbon fibre panels under the car would keep penetration from happening, but deformation can cause a short in the battery as well. The entire underside of the vehicle is an awfully large target compared to conventional fuel lines.

Thinking_J
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Re: Unanticipated incident
Thinking_J   10/9/2013 3:26:12 PM
3 inch diam hole !!? in 1/4" plate?.. Dang! that is a BIG hole (likely equate to 6-12" tear in lighter gage sheet metal)

Many new cars don't use any sheetmetal for their fuel tank.. it is 100% plastic. And, yes , for those reviewing things closely.. they do rupture much more easily than older designs (often very little protection from side impact)... We really aren't operating cars much safer from fire than the Pinto of years ago.

When the road debris is taking out large areas.. the size of the fuel line compared to the under side of the car starts losing it significance. (taking out the small target with a grenade)

And as stated earlier.. every 90 seconds a gasoline powered car in the US goes up in flames. Yea, there are a lot of them out there. And many are pretty old. But this doesn't appear to be viewed as a signficant problem by the public. Unless the media decides to make it a significant problem...(slow news week).

Nothing is without risk.

I don't see risks being reduced any signficant amount beyond the current design of the Tesla.

Is someone going to make a big deal out of the accidents caused by poor handling due to higher center of gravity on some cars?

Ban "high CG" cars!?.. Force the speed limit to 15 mph!? (to eliminate all these issues?)

I don't see it happening.....

 

 

Watashi
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Re: Unanticipated incident
Watashi   10/9/2013 5:16:55 PM
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Be careful what you ask for!  Nothing is too outrageous for the safety morons these days!

timbalionguy
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Re: Unanticipated incident
timbalionguy   10/9/2013 3:53:31 PM
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That said, I don't assume the bottom of the chassis is a simple flat plate, like the picture suggests. Flat plates in metal have very poor stiffness, and I seriously doubt the battery itself is part of the structural system. That plate either has soms sort of support beans attached, or more likely, is corrugated in a way to improve stiffness. The depth of the corrugations provides some protection, as well as the strength of the corrugations. If the battery were mounted so that a space of say, an inch existed between the chassis pan and the battery, you would mitigate a lot of deformation issues, especially from foreign objects on the road. Add the kevlar or carbon somewhere in there, and you have a strong, light weight protection system.

William K.
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Re: Unanticipated incident
William K.   10/9/2013 4:37:38 PM
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It should be quite obvious that the armor plate is not present in the picture that shows tha battery and drive assembly. And the curved piece of metal sounds like a piece of a leaf spring, which is some mighty strong material. And if the car was going 55 MPH, and the forward end of that chunk of metal caught a joint in the roadway, then it would be the equivalent of hitting a cold chisle with a hammer the weight of the vehicle, which would punch quite a hole in almost anything. I have seen what happens when a car with the front end of the muffler draging hit a joint in the road at about 30 MPH. It jammed the rear axel back a foot, ripping the spring mount out of the frame, and threw the car a few feet into the air.

I believe that the force of an impact can be described by the expression: Mass times Dv/Dt, and when there is a catch against a joint in the roadway that Dv/Dt approaches infinity. So the 75 Tons is probably a conservative estimate of the penetrating force.

It probably both ripped open the battery and caused multiple short circuits.

And the one gasoline spill fire that I was involved with had all of the skilled gas burning within 3 seconds. So I would say that this car was MUCH safer.

Charles Murray
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Re: Unanticipated incident
Charles Murray   10/10/2013 2:49:54 PM
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What a great explanation, William K. I realize it's hypothetical, but I think all of our readers would benefit by looking at it. Sounds dead-on to me.

William K.
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Re: Unanticipated incident
William K.   10/10/2013 3:47:48 PM
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Charles, The formula is quite real, derived from our friend F=MA, which while a sort of abstract formula is easily turned into a hard xample. And the incident of the car with the dragging muffler happened on Woodward avenue in front of the ice cream shop where we had stopped. It was quite a startling thing to see. The dragging muffler made enough noise that we all tured to look, which was just an instant before the impact.

I hope that when a very detailed analysis and studt is made of the wrecked Tesla that they can see just how far the battery pack was impacted, and possibly reconstruct just exactly what happened. Not that the media would ever be able to understand, but perhaps the event could be reconstructed by some crew like "mythbusters", or shown in animation. Then people would possibly have a clue as to what a rare fluke the incident was .

 

Watashi
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Chemical vs. Electrical
Watashi   10/9/2013 5:13:14 PM
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This is a freak incident that caused the destruction of an expensive and rare car.  But as the posts have brought up; what is really more dangerous gas or batteries?  I would submit that it is not as intuitive as one may think. 

To ignite gasoline, you must have the correct combination of heat, oxygen, and vaporized fuel.  Gasoline only provides one part of the fire triangle.  The combustion engine and the exhaust system provide a lot of heat, while the air provides the oxygen.

For a battery to ignite you need pretty much the same ingredients: heat, oxygen, and fuel.  However, a battery is a system.  When damaged, such as happened in this case, the battery is capable of generating intense heat.  The battery case (and possibly electrolyte) becomes fuel and oxygen is readily available from the air.

My first car was a '74 Plymouth Scamp that had a 318 V-8 with a Holley 600 four barrel carburetor.  The carb secondaries were cracked and would occasionally leak fuel onto the hot intake manifold.  There were times I opened the hood and found fuel standing on the engine after hard running.  Moral of the story is that gasoline is not as volatile as it seems.  

Gasoline has an ignition temperature of 500°F, so aside from the exhaust manifold of a car that gets very hot or an open flame it is not that dangerous.  To ignite gasoline with a spark requires the right concentration of fuel vapor to be present, which is not always reliable.

dirtyrube
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Fire Suppression
dirtyrube   10/11/2013 8:54:11 AM
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I realize it's unrealistic to design for every possible scenario and trying to prevent the fire before it happens is the goal but why not focus on minimizing and controlling the fire once it has started. Fire suppression has grown leaps and bounds over the past decade and deserves more consideratioin in automotive design. Stat-X is one of the companies that I have worked with first hand and has an incredible line of fire suppresion products that are very inexpensive and non-hazardous to the occupants of the vehicle. The US military currently have systems in place in the engine compartments of many of their vehicles and NASA's "crawler" also utilizes Stat-X fire suppression devices. I believe if a fire suppresion device similar to what I mentioned above were installed on the tesla, this incident would have been avoided all together. http://www.statx.com Here is the website in case you would like more information on the fire suppresion capabilities.

markr
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why EV fires get reported
markr   10/11/2013 6:10:00 PM
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Part of the reason that fires in EV cars get reported is becasue they are so rare. 

In the US, there at 150,000 car fires every year [1] or 410 each day. How many of them make national news? 

In the UK, it is estimated that 1 in 2000 cars accidently catch fire annually.[2]

If the Model S had a similar record, 6 would have caught fire in the last year.

When are the manufacturers of gasoline cars going to provide engineering solutions to this "troubling situation"?

[1] https://www.nfpa.org/safety-information/for-consumers/vehicles

[2] http://webarchive.nationalarchives.gov.uk/20120919132719/http://www.communities.gov.uk/pub/894/FireStatisticsUnitedKingdom2003PDF1724Kb_id1124894.pdf

 

Charles Murray
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Re: why EV fires get reported
Charles Murray   10/11/2013 6:33:17 PM
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I have little doubt that your statistics are right, markr. Lithium-ion fires get reported for two reasons: (1.) Prior to the lithium-ion "boom," battery experts predicted that lithium-ion battery packs would have overheating problems if they were not engineered properly. Luckily, they have been engineered properly (with rare exceptions), which is why your point is on the mark. (2.) The devil you don't know is always more frightening than the devil you do know.

Pubudu
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Re: why EV fires get reported
Pubudu   10/12/2013 3:56:24 AM
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Markr thanks for the links its gives great insights. 

Elizabeth M
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Re: why EV fires get reported
Elizabeth M   10/14/2013 3:30:32 AM
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Thanks for bringing up this point, markr. It is a valid one. I think in some cases people like to point to the fires in EVs to shed a negative light on these type of vehicles. I still think the battery fires are a bit troublesome exactly for that reason--if promoters and manufacturers of these vehicles want to make the mainstream, they need to be without these type of problems and in some ways beyond rapproach.

Charles Murray
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Re: why EV fires get reported
Charles Murray   10/14/2013 6:22:32 PM
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Yes, I agree, Liz. Markr's point is absolutely valid.

Thinking_J
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Re: Unanticipated incident
Thinking_J   10/13/2013 9:26:12 PM
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Mr. Architect (Bill):

I did not intend to provoke, only to provide a perspective on the nature of risks - as related to this car as compared other cars.

If I offended , please except my appolgies.

I do listen and hear. I didn't say there were no risks. I just indicated the real risks were no more than what the public currently is comfortable with when driving other cars (People regularly die in GM cars on fire .. a sad fact)

Every car being produced today has many, many engineers involved before it is produced - it is a team effort- even at the smaller car company. And this car's shape (beauty?) had little (nothing?) to do with being penetrated on the bottom. Obviously you do not hold Mr Franz in high regard, but please don't condemn the car because of his reported level of involvement.

All production cars are subject to safety testing by the government - including side impact testing. Regardless of those involved in the design of the car.

I see no relationship between "beauty" and "safety" (terror). There are plenty of ugly, less safe cars out there.

"beauty" is a subjective term... I am sure there are some that don't like the looks of this design.

The term "safe" is nearly as subjective as "beauty".

I am sure that any object capable of putting a 3 inch diam. hole through 1/4" plate will put a hole through the frame work protecting the battery of a GM Volt. Over 25,000 lbs of pressure on a sharp, steel projectile will do significant damage to any car. Glad it wasn't put through the driver or passenger.

I don't see any company (including GM) producing cars any safer that this one.

My comment: "I don't see it happening".. indicates my hope that the public DOES realize there are limits to the level of protection a car can provide and still meet all of it's other requirements.

Old pilots' observation:

What is a airplane?  Ans: a bunch of compromises, flying in close formation.

It is applicable to cars as well...

 

 

TJ McDermott
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FOD catcher needed
TJ McDermott   10/15/2013 7:16:41 PM
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Tesla need only add a FOD catcher to the front of the vehicle to prevent this problem in the future, right?  Something akin to the sloped wedge on the front of steam locomotives, aka cow-catcher?  No, I'm not serious about it.

The Concorde was mothballed because of a FOD incident.  I do hope Tesla weathers this event.

bobjengr
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BIZARRE AND TESLA
bobjengr   10/21/2013 5:17:42 PM
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Excellent post Charles--very informative.  If I may, do you know the ground clearance for the Tesla model involved?  I suspect, for aerodynamic reasons, it's quite small.  I'm sure the engineers considered road debris when designing the overall body but just curious to know what that dimension is.  Some years ago, while traveling to Louisville, I hit a "gator"--a tire section thrown from a semi wheel.  It was at night and I did not see the section lying on the road.  Wiped out the left headlight and removed some of the cowling from the underside of the car.  I was in a rented Ford Taurus.  It created quite a sensation for me and my passengers.  The car was drivable but definitely needed repairs before returning home.

Charles Murray
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Re: BIZARRE AND TESLA
Charles Murray   10/21/2013 5:52:31 PM
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I believe the ground clearance of the Model S is six inches, bobjengr. Yes, those "gators" can be thrilling, to put it nicely, especially if you're near the truck when it comes off.

Thinking_J
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comparisons between Tesla and GM product safety
Thinking_J   11/2/2013 6:02:20 PM
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Three different news articles... countless perceptions to be derived from them.

Chevy volt:

2010....http://www.freep.com/article/20111126/BUSINESS0104/111260324/

"the Volt's batteries caught fire three weeks after the crash test."

2012.....http://www.forbes.com/sites/joannmuller/2012/01/20/government-ends-probe-into-chevy-volt-fires/

Two years later.. "NHTSA concluded there was "no discernible defect trend" in the Volt, adding that GM's plan to reinforce the area around the battery pack with an extra piece of steel would reduce the potential for battery intrusion in the event of a severe side impact."

First thought: Two years later and now they are putting in extra steel to protect the battery?.. Where was all that great GM testing before they released the product to the market?
(everyone panic!)

Second thought: .. "no discernible defect trend" to begin with. (eh, no big deal)

Which thought did you have?

Tesla:

http://www.forbes.com/sites/michelinemaynard/2013/08/22/tesla-gets-a-little-carried-away-has-hand-slapped-by-feds/

"It received a five-star rating for front, side impact, rollover and pole penetration".


I believe the second article's ending statements put things in a reasonable perspective:

"All vehicles have some risk of fire in the event of a serious crash. GM has said all along that it's important with any crashed vehicle, not just the Volt, that the battery be disconnected and drained of all energy.

NHSTA said it was developing safety guidelines for electric vehicles that it would share with consumers, emergency responders, tow truck operators and storage facilities."

It will take a long time to educate all first responders (and the general public) to the proper handling of electric car fires.

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