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Tesla Semi catches fire on I-880

62 points metadat 2 hours ago 39 comments

vessenes 1 hour ago | parent

The article is confusing - at one point it says the truck left the road, hit a bunch of stuff and caught on fire. At another it says they don't know if it was a battery pack fire that spread. I'll be interested to read the final safety reports and see if this was just an unlucky crash or something really bad happened with all that lithium.

_Microft 1 hour ago | parent

The accident in which the vehicle left the road happened in 2024.

close04 1 hour ago | parent

> I'll be interested to read the final safety reports

Are you still confident that the final reports will be free of interference and the agency investigating anything Tesla (Musk) related won't be gutted before it gets the chance to issue anything damaging?

mlmonkey 1 hour ago | parent

That's a different accident, and the last one involving a Tesla Semi (before the current one). The point they're making is: that one involved an actual crash, but this one did not. So we should investigate this thoroughly to see what happened (as the NTSB is going to do, of course), because large vehicles should not spontaneously combust on a public highway, especially one as busy as the I-880.

On a related note: I wish companies like Tesla, which are conducting live experiments on public highways and thereby inconveniencing 1000s of people when an experiment goes awry, are held accountable and forced to compensate those who got stuck on the highway, missed doctors appointments, job interviews, deliveries, etc. Maybe something like a fine of $5000 per driver impacted should be levied, and given to each driver?

bdamm 1 hour ago | parent

This is the point of insurance no? It's the underwriter's job to figure out what the risk probability of insuring a specific vehicle is, and then to represent that risk in future lawsuits while paying out the named insured in the meantime. If you think the traveling public should be party to insurance from vehicle collisions in general, then that's a legislative framework change for all road users (and you can bet your behind that will mean higher premiums for everyone, which I'm personally ok with. We've externalized far too many costs. Let's ban writedowns for exploratory oil drills too.)

2OEH8eoCRo0 1 hour ago | parent

What's confusing? First sentence of article:

> A Tesla Semi caught fire on Interstate 880 in Hayward, California, on Tuesday evening, and there was no crash.

Further:

> The driver told officers the truck caught fire and that they didn’t know why. No other vehicles were involved.

orwin 1 hour ago | parent

I think you misread. The article state tesla Semi has had 2 fire in 2 years. The first one because the truck hist stuff and left the road in Nevada, the second (this one, the subject of the article) in California for unknown reasons. This is relevant because the Tesla semi fleet is small (86 vehicles 2 years ago, probably below 500 atm) and because battery fire are hard to stop, so we want to know what caused it. If EV fire last 10 time longer than diesel fire, but happen 10 time less often (we need more studies but it seems this is the initial consensus), this is not really an issue, but if they happen more often, we _need_ to know why and fix it.

Also i don't want trucks to catch fire everytime they hit a cow or a boar, the roads around where i used to live would be consistently closed :/

cucumber3732842 1 hour ago | parent

Approx one (with a big error bar) fire per 100 vehicles per year sounds about right based on my unscientific dealings with auction oil field trucks.

My gut feel is that vehicles of all types seem way more disposed to fire than stuff from the 90s through 2010s.

hansvm 47 minutes ago | parent

For some other unscientific findings, that'd suggest 5 vehicle fires per year just from residents of my apartment complex. I've seen 1 in 8 years, and that was arson.

bryanlarsen 11 minutes ago | parent

Those trucks are probably doing over 200,000 miles per year and your apartment's cars under 20, so the fires/mile ratio seems comparable.

ortusdux 1 hour ago | parent

Are battery fires like this more damaging to the road surface vs a diesel fire?

darksaints 1 hour ago | parent

Yes

zerocool0101 1 hour ago | parent

how?

xxs 56 minutes ago | parent

You can't use a fire extinguisher for one to put it down. Li-Ion effectively self-sustain when ignited.

The only version of putting it down is letting it burn out.

Morealso diesel is hard to ignite on its own, hence the ICE use compression not spark

close04 1 hour ago | parent

Diesel fires are put out much faster than battery fires especially when the battery is huge and fully charged. Battery fires are also much hotter, up to 1000 C (~1800 F), metal fires are no joke.

Diesel damages the asphalt more in different ways. It attacks the binder in the asphalt and softens it up (after all they are both byproducts of the same crude oil precursor and just want to recombine). This process takes even days so if the cleanup is fast there's minimal damage. Most of the fuel that doesn't burn runs to the side of the road anyway.

tartoran 1 hour ago | parent

Which fumes are worse, from EVs or diesel filers?

close04 59 minutes ago | parent

Honestly no idea. But after receiving multiple fire trainings and talking to trained firemen, I have to say that all else being equal (and gun to the head because I actually want neither) I'll take a diesel fire over a battery fire any day.

A lot of dangerous fumes come from the other material burning around the source. And at 1000C plenty of neighboring stuff decides to burn.

jordanb 52 minutes ago | parent

You don't want to breathe either, but the answer generally is battery fires which can produce extremely toxic gas like hydrogen flouride

https://m.youtube.com/watch?v=lADLvwAJs-c

https://en.wikipedia.org/wiki/Hydrogen_fluoride

ourmandave 16 minutes ago | parent

Yeah, that's on Derek Lowe's list of things he won't work with.

https://www.science.org/content/blog-post/things-i-won-t-tou...

ggreer 44 minutes ago | parent

Lithium battery energy density is much lower than petroleum, so the difference between a fully charged 100kWh battery (which weighs over half a ton) and an empty one is less than 3 gallons of diesel. Most of the energy expended in a battery fire is from the electrolyte reacting with the cathode material.

Over/under-charged batteries are a safety hazard because they can generate hydrogen gas which can initiate a fire, but the energy released from the fire will be pretty much the same.

jacquesm 10 minutes ago | parent

Lithium fires are brutal, they're extremely fast and the toxic gases are just as dangerous as the fire itself:

https://www.reuters.com/world/asia-pacific/about-20-bodies-f...

paxy 44 minutes ago | parent

Regular cars usually burn out in 30 mins or less. It's a fair assumption that a 10-15 hour fire would be more damaging.

mingus88 32 minutes ago | parent

I’d think it really depends on the heat and proximity to the road

If a battery pack burn less hot and sits higher off the roadway, I can see it being less damaging

breckenedge 39 minutes ago | parent

Lithium fuel can melt asphalt seams

ggreer 35 minutes ago | parent

I'm not sure, but diesel fires are definitely more of a risk to people. Fuel can quickly spread and ignite before people in the vehicle (or bystanders) have a chance to escape. Lithium battery fires are more contained because individual cells spew flame, which heats up nearby cells, which then undergo thermal runaway. This means that battery fires take longer to release their energy, which is annoying for extinguishing them, but good for anyone who needs to get out of the wreck.

jacquesm 14 minutes ago | parent

> I'm not sure

> definitely

If you're not sure, why the definitely?

Lithium packs can light up faster than you sketch here. The process you describe is correct in sequence but it takes about as long to read that sentence to get to a car that is engulfed in flame. More than one person died from the combination of toxic gases and heat before they managed to get out of the car.

Lithium Ion is a very bad battery type for anything that should be safe, LFP is far better and LTO is better still.

leonidasrup 11 minutes ago | parent

There is a big difference between diesel powered engines and petrol powered engines. Diesel is much harder to ignite and this was for example big advantage for diesel powered tanks during World War II, in comparison to gasoline powered tanks.

"They introduced many innovations as they built their designs, including bell crank suspensions, as pioneers in amphibious tanks, and the use of diesel engines that were less likely to catch fire compared with gasoline tank engines that were being used at the time."

https://en.wikipedia.org/wiki/Tanks_in_World_War_II

The answer from an actual firefighter:

" Diesel has a much higher flashpoint. This means the speed of deflagration is much slower. It cannot convert the diesel to vapour as quickly so can't disperse the fuel as quick to spread the surface area.. "

" Leaking petrol is much more dangerous in an accident. It is far easier to ignite. If any leaking petrol contacts the exhaust or brake discs it could ignite causing rapid flame spread trapping people in the car. Diesel won't do this. "

https://www.quora.com/Is-it-possible-for-diesel-cars-to-expl...

lakeviewterrace 17 minutes ago | parent

Yes, but you can leave satisfied knowing no fossil fuels were burned in the creation of said fire.

dekhn 13 minutes ago | parent

Depends on context and the location of the road surface and the nature of the explosion.

https://www.sfgate.com/bayarea/article/Tanker-fire-destroys-...

(Also, the rebuilding was epic, the only time I've seen the state and a contractor move quickly: https://longreads.com/2024/07/15/rebuilding-the-maze/ )

fourseventy 28 minutes ago | parent

Is there an article every time a Mack Truck catches on fire?

dpkirchner 23 minutes ago | parent

Yeah.

phyzome 21 minutes ago | parent

New technology bears additional focus.

georgeecollins 14 minutes ago | parent

There is every time the fire shuts down the 880 for ten hours.

declan_roberts 27 minutes ago | parent

You know a Tesla was involved in an accident because they always make it part of the headline.

pengaru 25 minutes ago | parent

Wow, not much left of the semi - would love to see a photo of the metallic puddle it's presumably become...

dam_jackalopes 9 minutes ago | parent

I worked at a "Semi" OEM where we were doing work on battery, hydrogen powered, etc. development as part of the SuperTruck effort and these events are what kept us up at night. Really glad the driver was able to get out.

I suspect that we're going to socialize the costs for getting first responders prepared (in so much as we actually do try to get them prepared) for these type of events. As a concept, that's fine but it leaves a really bad taste in the mouth when you're doing that to the benefit of an actor like Tesla.