Model S Accident/Fire

[Blurry_Eyed]

FYI - I'm pulling this quote from the Northwest Tesla Owner's email thread - This is from Bob Jordan, who is a Tesla owner and also works at KIRO - 7 News here in Seattle.

'A spokesperson for the Kent Fire Department told KIRO7's assignment desk that the cause of the fire was not known; that KFD will not investigate further; that it will be up to Tesla to conduct an investigation. In truth, NTSA may get involved here, given the scrutiny that electric cars are getting.'

The thought about NTSA is speculation on Bob's part, but just so you all know, it looks like there won't be an 'official' investigation of this at this point. The Kent Fire Department here in the area just looked at it as another car on fire and they took care of it with what appear to be no issues. I'd assume there were no people harmed in the incident either since KFD is not investigating further.

 

[dirkhh]

*getting*popcorn*

Sorry, can't find red letters. Is it OK if I continue in boring black? I didn't accuse anyone in particular, but if the shoe fits, CO, feel free to put it on.

I was actually expressing surprise by the rampant speculation in the absence of factual data on both sides of the argument...

But this is fun, let me join.

I think it is most likely that holders of large TSLA short positions planted a large metal object, laced with flammable substances at this intersection, waiting for a Model S to come by and then quickly moved it in front of the approaching car.
They then blocked the cell phone connections and manufactured a traffic jam to prevent police from quickly getting to the site.
They continued to drive their story by posing as fire fighters and pretending to fight the fire while in fact waiting for the planted "random bystanders" to take cell phone pictures and videos to post all over the web.
They also abducted the driver so she can't tell what truly happened. (or maybe she was part of the setup... not sure about that one - but it definitely was a woman)

I think this matches all the known facts and is the best explanation of what happened.

*facepalm*

 

[CapitalistOppressor]

Yes, you could see interior of the pack in the "Battery discussion" part of the forum. 60 kWh pack consist out of two blocks, each contain 7 sections, with ~450 cells in each of them. It was speculated that in 85kWh pack there are 16 instead of 14 "sections". If anything "cascades"(I personally do not think so), the cascading was probably contained within such section.

Mine IMHO on the matter, something caught small fire in the front of the vehicle (hydrolic fluid, 12v battery wire etc), which in turn ignited whatever was stored in the frunk. It is probably took quite some time till that big of a fire we see in the video to get going. It is not clear how long it took from the moment of incident to emergency teams to arrive, the video could have been easily taken half an hour after Model S stuck that big metal object.

That sounds similar to the interior of the RAV4 pack, which seemed to have fairly substantial partitions.

 

[brianman]

Thanks, Blurry.

 

[ggr]

The pack is not designed to have a large metallic object rip through it either. I agree, more than one cell would have needed to combust to cause a cascade.

That said, if this was not a battery fire, then the Tesla statement was PR malpractice. They must know that a battery fire is the primary concern, and if this was not a battery fire they should have specifically denied it.

Given that we have a cause (metallic debris) and a plausible effect (a cascading failure from a pack that was ripped open), I'll take that and run with my speculation in the absence of a statement by Tesla otherwise.

OK, I think there may be a terminology mismatch going on. CO, you keep saying "cascading failure". That is when one (or more) cells overheat due to a short or thermal runaway or something, and catch fire, and then cause other cells to catch fire. Now it looks to me like the fire was caused by one (or probably many) cells shorting out and catching fire, and I don't think Tesla is denying that. However, in a cascading failure, you could expect the entire battery pack (and car) to have incinerated in a couple of minutes, well before the fire engines got there. I think the lesson here is exactly that there was not any cascading to the failure!

(later addition Lots of people have commented already, but I am still trying to clarify. Maybe someone is thinking that thermal runaway and cascading failure are the same thing. When you do big damage to a Li-Ion cell, or short it out, it gets hot, which breaks down the internal insulators, and allows current to flow, which makes it hotter still, etc., until it catches fire. That's thermal runaway. The 787 fire did both; one cell caught fire from thermal runaway due to overcharging starting the vicious cycle (at least that is the only plausible reason known), then the fire spread to the other cells in a cascading failure.

 

[rolosrevenge]

Ok, now we're in fantasyland. It was confirmed that the car "collided with a large metallic object"; it wasn't confirmed that the car ran over something small enough to go under the car and still be strong enough to rip through the 1/4" steel battery pack which despite losing cells and coolant all over the road continued to operate till the driver could pull over.[/sarcasm. I apologize]

There's any number of things which could have happened so please let's stop insisting that something "ripped into the battery pack" when there is zero evidence to that.

Fair point, there are a number of things that could have happened. I didn't say that's what happened, but merely stating that the Tesla designed safety systems would work that way if the collision was one that resulted in a pack breach under the car. That scenario seems very plausible to me. Some big chunk of metal falls off of the back of a big truck, the driver doesn't see it, drives over it and hears a load noise, then the car warning starts flashing telling him to pull over. He does, and shortly thereafter a fire starts.

Another scenario is that he smacks into something large and metallic that crushes the front end of the car. However, he doesn't seem to notice it ("The car’s alert system signaled a problem and instructed the driver to pull over safely"). Something in the crushed frunk lights on fire, even though that behavior hasn't been happened to any other front end collisions.

Then again, it could be all manner of things that I know nothing about. I'm just guessing because that's what we do on a web forum in the absence of facts, if not, the whole thread would be "That's sad" "I wonder when Tesla will tell us anything" "I wish the guy filming knew how to turn his smartphone horizontal because vertical video sucks" etc.

 

[yngwie_2012]

*getting*popcorn*

Sorry, can't find red letters. Is it OK if I continue in boring black? I didn't accuse anyone in particular, but if the shoe fits, CO, feel free to put it on.

I was actually expressing surprise by the rampant speculation in the absence of factual data on both sides of the argument...

But this is fun, let me join.

I think it is most likely that holders of large TSLA short positions planted a large metal object, laced with flammable substances at this intersection, waiting for a Model S to come by and then quickly moved it in front of the approaching car.
They then blocked the cell phone connections and manufactured a traffic jam to prevent police from quickly getting to the site.
They continued to drive their story by posing as fire fighters and pretending to fight the fire while in fact waiting for the planted "random bystanders" to take cell phone pictures and videos to post all over the web.
They also abducted the driver so she can't tell what truly happened. (or maybe she was part of the setup... not sure about that one - but it definitely was a woman)

I think this matches all the known facts and is the best explanation of what happened.

*facepalm*

i like this idea...

btw, months ago i was asking myself what has to happen so that tesla stock fell down? I was thinking about conspiracy theories that a major automaker hiring someone putting a tesla on fire.

 

[rolosrevenge]

when those who are suggesting such a thing know next to nothing about the battery design other than what they've read online and through other people's speculations.

:crying:

 

[kevin99]

never mind.

 

[CapitalistOppressor]

OK, I think there may be a terminology mismatch going on. CO, you keep saying "cascading failure". That is when one (or more) cells overheat due to a short or thermal runaway or something, and catch fire, and then cause other cells to catch fire. Now it looks to me like the fire was caused by one (or probably many) cells shorting out and catching fire, and I don't think Tesla is denying that. However, in a cascading failure, you could expect the entire battery pack (and car) to have incinerated in a couple of minutes, well before the fire engines got there. I think the lesson here is exactly that there was not any cascading to the failure!

No, as I've already stated, the pack is designed specifically to prevent a cascade failure from spreading to the passenger cabin, and in fact there are internal partitions to help prevent it from spreading within the pack. But any of the cells that are not partitioned are vulnerable to cascade failure if enough heat is present.

It takes more than one cell to do so, or else it requires that the cells be displaced so that the tops and bottoms are not isolated in the racks, and/or if the cells displace enough to be closer together and you get sidewall breaches in the cells as they deform.

Once a section starts to cascade, pressure will build and the venting system will force burst panels open at the sides of the battery along whatever section it is. Those panels probably open into the underframe, which would direct the energy forward to the front of the vehicle (since thats the only safe place to put it).

So it might well be that we only had a failure of a single section, or even just a partial failure. All that is required is that there be enough energy (pressure/heat) built up in the battery to activate the burst panels and vent the heat.

The point is, that a "cascade" just means one cell (or a set of cells) heating up enough to cause other cells to combust. It doesn't have to mean that the cascade will continue through the entire pack.

 

[HongKongFan]

AP reports

The incident happened Tuesday after 8 a.m. as the driver was traveling southbound on state Route 167 through Kent, said Trooper Chris Webb of the Washington State Patrol. The driver stated that he believed he had struck some debris on the freeway, triggering the fire, Webb said, but a trooper who responded to the scene was unable to locate any objects on the roadway.

So was it a collision with a "large metallic object" as Tesla PR stated?

 

[CapitalistOppressor]

AP reports

So was it a collision with a "large metallic object" as Tesla PR stated?

Who knows. The trooper didn't find it, which would tend to point to something smaller, but an impact could send even a large piece of metal flying into a bush or whatever.

 

[dsm363]

The front of the car looks smashed. A large object seems more accurate. Where is the state trooper report up already?

 

[CapitalistOppressor]

*getting*popcorn*

Sorry, can't find red letters. Is it OK if I continue in boring black? I didn't accuse anyone in particular, but if the shoe fits, CO, feel free to put it on.

I was actually expressing surprise by the rampant speculation in the absence of factual data on both sides of the argument...

Actually, there is plenty of factual data available. We have a wealth of data and a news release by Tesla.

The only thing we are short of is factual conclusions, hence the rampant speculation.

 

[Doug_G]

Yeah, well I really doubt the state trooper had a good look for the object, which was probably (a) was back 200 feet and (b) flew off into the bushes. So any report about the object is likely pure speculation on the part of the trooper.

The initial state trooper report for the Peekskill meteorite that hit a car stated that the damage was done by "a large male". Yeah, the meteorite punched the top of the trunk through the floor and into the driveway. That was a heck of a large male.
[/QUOTE]

 

[yobigd20]

I also agree that if the main battery was not involved in the fire at all, Tesla failing to mention that is a very big failure.

I doubt they've had time to investigate it yet. We don't want them making false statements. Their just carefully wording their statements until they can confirm on their own.

 

[CapitalistOppressor]

Yeah, well I really doubt the state trooper had a good look for the object, which was probably (a) was back 200 feet and (b) flew off into the bushes. So any report about the object is likely pure speculation on the part of the trooper.

The initial state trooper report for the Peekskill meteorite that hit a car stated that the damage was done by "a large male". Yeah, the meteorite punched the top of the trunk through the floor and into the driveway. That was a heck of a large male.

Lol.

Yes, the only conclusion we can draw is that whatever it was probably (hopefully?) got knocked off the freeway. An officer isn't going to waste his time looking very hard. They have the car, and I think we can agree that a sufficient amount of metal is enough to cause whatever damage they end up finding.

 

[Doug_G]

Here's a very sensible sounding news article on the event: First fire in a Tesla Model S sparks all the expected questions | Motoramic - Yahoo Autos

Every year, about 180,000 vehicles catch fire across the United States, so a single car fire outside of Seattle on Tuesday that injured no one wouldn't usually catch much notice. Except that the blaze shown above was the first reported fire of a Tesla Model S — and for a company built around making electric vehicle tech mainstream, the fire sparked the old question about whether its batteries were to blame.

There's no sign in the video of a widespread battery fire; the battery pack in the Model S runs from roughly the front to rear axle on the bottom of the car; the fire in the video above never breeches the passenger compartment. The front of the Model S is mostly empty space; its electric motors are in the rear, and the flames appear strongest around the carpeted front trunk compartment.

Lithium-ion batteries can pose a new kind of risk, but for now there's nothing in this case to suggest there anywhere near as flammable as the gallons of gasoline millions of drivers rely on daily.

 

[CapitalistOppressor]

I doubt they've had time to investigate it yet. We don't want them making false statements. Their just carefully wording their statements until they can confirm on their own.

Honestly, this might be true if the accident just happened. I had heard somewhere that it happened earlier in the week, but if it happened today they clearly would not have had time to see the vehicle. Their engineers might be arguing just as much as we are.

 

[lgagliardi]

I know it is crazy but someone might have caused this on purpose. We all know the stock has been on fire(no pun intended) and the stock just keeps going up. You know some people have lost "substantial" amounts of money on the stock and could have felt this would really cause it to drop. I hate thinking this way but I believe it to be possible. That said, I still think the stock will rebound and continue to go higher. Hopefully no one went to this crazy level of trying to knock the stock down!