Source: Firefighter in a rural dept

Seems like it was a precaution, rather than needed.

Was it needed as part of the process in this instance? Yes. Was it needed to extinguish the vehicle in this instance? No.

Safety measures are put in place for a reason.

It's not about being more efficient - it's about kicking out one or more legs of the fire triangle, with water, that being heat and oxygen. The problem is that physics dictates that overcoming the BTUs being put out by a battery fire requires rather a lot of water.

Use of other liquids to absorb this heat is ... problematic. One, you have to transport it to the fire, and two, runoff. It's bad enough having structure fire water runoff going to the ground and water supply, let alone another (most likely noxious) chemical.

Though I guess normal car fires would have gasoline-tainted runoff anyway!

Australian here, but I can’t imagine there’s much difference on this issue.

A big battery "fire" is not really a fire, in the normal meaning of that word.

The job the FD faced might better be described as "supply continuous cooling, until the self-powered/no-oxygen-needed battery meltdown runs low on electrical energy". Though if the FD's training & equipment is for traditional fires - then they are stuck using a "pretend it's a fire, and call in 10 more tanker trucks" playbook.

How long will it take for that to happen in one of these semis? What if the fire needs to be extinguished before then because of risks it poses to surroundings?

You're pretty much SoL, because the "fire" is more like a pair of electrical cables that are shorting together.

With seriously specialized heavy equipment (and probably an expendable robot or few), you might tap into the semi's electrical system, to drain off some of the electrical energy to a giant resistor. Or chop the battery out of the possibly-mangled semi's structure, and haul it away in a "burning battery containment" truck.

The battery fire is self sustaining, so only way to stop it is large amounts of continuous cooling for a long time. That's what the water container is for.

At least that's the method used in the Netherlands. Which obviously isn't practical for a semi truck sized fire.

Edit: Here is a picture from a news article: https://i.regiogroei.cloud/4561b78f-d49a-3ecc-adb4-6f535f896...

[1]

    household use, which accounts for around 12 %. On average, 144 litres of water per person per day is supplied to households in Europe.

which is around 210 cubic meters. Is my math off?

Not my area of expertise, but I remember in chemistry class we had a literal bucket of sand for certain types of chemical situations.

Burying it insulates it, which will increase the runaway, but isolate the issue. It's good for small batteries like cellphones and laptops because it allows you to move the battery somewhere else and contain the fire, but doesn't do anything to retard the runaway.

Water can cool it off and slow down/potentially halt the runaway. Someone smarter than me would need to comment on what to do after it's halted, because I assume it's still a problem waiting to reignite at that point.

https://en.wikipedia.org/wiki/Thermal_runaway#Batteries

Edit: This actually is a potentially interesting idea, a tomb vehicle that basically encases the burning vehicle in a heavily insulated trailer for relocation.

Same thing happens to e-bike batteries; you can find video of a man being spontaneously incinerated after carrying his e-bike battery into an elevator.

And of course the same thing happens to battery storage for the grid. Battery farms spontaneously start burning and it just spreads and spreads.

I think of this every time somebody argues that nuclear fission can be replaced by solar/wind + huge battery farms. For example, see the recent discussion here:

https://news.ycombinator.com/item?id=41526789

Imagine the battery fire.

If that is possible, can it be done while the car is parked as well?

Also, this was a little ironic…

> The Tesla truck, driven by an employee, was headed to the company’s battery factory in Sparks, Nevada

The part that concerns me is once electric cars are more ubiquitous, say 50% of cars on the road. How will we handle a pileup, where there could be five cars that all need the same level of fire department effort? Could there be some domino effect?

I don’t think that’s standard vehicle fire practice.

EDIT: 500 gallons was originally just a wild guess, but here's an article where some firefighter gives 500-1000 gallons range: https://www.independent.co.uk/climate-change/tesla-crash-dri...

> Fire trucks" - I'm assuming you mean Engines

No-no-no, an engine is a part that makes a fire truck move. Fire trucks usually have a diesel engine.

tips fedora

Yes, correct, engineer.

(The generic term for some type of fire-fighting vehicle is Apparatus.)

https://www.tesla.com/firstresponders

I'm not sure the volume is there right now to justify a new company, but maybe 10 years from now? Just thinking out loud.

a rare case when "ton" is an understatement. 50,000 gallons is almost 200 tons.

If you really did go it alone, I think you could target the FDs in metros with outsized EV populations. I believe San Diego is among the top of the list.

Solid state batteries as supposedly safer.

They definitely need to be prohibited from using tunnels that don't allow flammable cargo. There are many tunnels that don't allow gasoline tankers.

I imagine in the future they'll look back on when we drove cars that were so combustible (ICE or lithium-ion) like how we look back at when everyone had lead-based house paint or asbestos ceilings.

Has it been studied or researched?

https://www.ri.se/sites/default/files/2020-12/FRIC%20D1.2-20...

> Environmental impacts - electrical vehicles

> • Water analyses of selected metals relevant for batteries in electric vehicles did not show any lithium, and only low concentrations of cobalt.

> • This indicates that batteries in electric vehicles did not contribute to pollution of nearby water resources.

Pouring tons of water is just not a good way to put out the fire.