California firefighters had to douse a flaming battery in a Tesla Semi with about 50,000 gallons (190,000 liters) of water to extinguish flames after a crash, the National Transportation Safety Board said Thursday.

In addition to the huge amount of water, firefighters used an aircraft to drop fire retardant on the “immediate area” of the electric truck as a precautionary measure, the agency said in a preliminary report.

Firefighters said previously that the battery reached temperatures of 1,000 degrees Fahrenheit (540 Celsius) while it was in flames.

The NTSB sent investigators to the Aug. 19 crash along Interstate 80 near Emigrant Gap, about 70 miles (113 kilometers) northeast of Sacramento. The agency said it would look into fire risks posed by the truck’s large lithium-ion battery.

  • SpaceNoodle@lemmy.world
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    7 days ago

    Maybe don’t use water to put out a fire that can’t be put out with water. Aren’t these supposed to be professionals?

    • NaibofTabr@infosec.pub
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      7 days ago

      The purpose of the water is to cool the wreck and the area around it while the metal fire burns itself out, because waiting it out is the safest option for the firefighters.

    • shaun@lemmy.world
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      7 days ago

      Flooding the batteries with water is the best way to put out a lithium-ion battery fire.

        • cm0002@lemmy.world
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          7 days ago

          Maybe for smaller things, a regular car maybe.

          But by the time a suitable digging machine arrives on scene and digs a big enough hole for a semi it’d probably be faster to flood it with water. Not to mention what might be underneath the ground, so they’d also have to spend time determining if there’s any gas lines or whatever before they dig so they don’t make a much bigger problem

        • frezik@midwest.social
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          6 days ago

          Lithium fires are self-oxidizing, so that won’t work. Burying it helps keep it from spreading, though.

      • frezik@midwest.social
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        6 days ago

        It isn’t.

        https://youtu.be/qgP7KkDesBo?si=XNb_yZYwA943t0lP

        Water seems to put it out for a bit, but the reaction is self-oxidizing and starts right back up again. That’s why it takes so much water; fire fighters keep dowsing it and then doing it again. Takes all day, and the whole thing burns away in the end.

        The way to do it is, if possible, tow it somewhere away from other things, keep the fire from spreading, and otherwise let it burn. For cars, there are fireproof blankets coming on the market to contain it. Semi-trucks are probably too big for that, though.

    • GeneralEmergency@lemmy.world
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      7 days ago

      For as much as people want their Musky circlejerks. This is really just a problem with the switch the EVs that people aren’t willing to accept.

      There is no way to really stop an EV battery fire.

      The batteries in these cars are made up of several cells, packed into a watertight, fire resistant box. When just one of those cells goes it’s over. It can create a chemical reaction that can ignite the cells without the need for oxygen, pure heat will set them off.

      The only real way of dealing with them is to let them burn themselves out, and even after that they aren’t safe and could reignite.

      • SpaceNoodle@lemmy.world
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        7 days ago

        Two.

        The best policy is to not puncture batteries, and train others to not do so.

        The next best is to know to smother them.

        • shoulderoforion@fedia.io
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          7 days ago

          how do you smother a semi fire on the highway, a) with a water tanker or b) with a sand tanker, how many municipalities have a sand tanker on hand, how do those sand tanker hoses work again, lots of sand tanker slingers round your parts cowpoke?

            • Goronmon@lemmy.world
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              6 days ago

              Isn’t that foam what we are discovered is leeching into ground-water supplies everywhere and is super unhealthy for everyone?

            • NaibofTabr@infosec.pub
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              7 days ago

              Foam suppressant is appropriate for liquid fuel fires like oil. It is not appropriate for metal fires.

                • brygphilomena@lemmy.world
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                  6 days ago

                  Not who you responded to, but that’s an interesting source. I’m intrigued by a textile company claiming to be experts in lithium ion fires.

                  It sounds more like options for preventing a fire to spread. It’s also including CO2 extinguishers under “foam” which they very much aren’t, making me doubt the rest of their blog post.

                  Extinguishing fires can work largely in two different ways. Either by smothering a fire or by cooling a fuel below it’s flash point. Quite often they put out a fire by doing both. A fire that contains an oxidizer cannot be smothered, but smothering can help prevent other materials in a vehicle from being able to burn along with the batteries. Cooling down a large, vehicle sized lithium ion fires takes an incredible amount of water. However, the cells themselves contain so much energy that their failure produces more thermal energy than water is able to remove.

                  Is water the best to put out large EV fires? Nope.

                  Is water good at preventing fires from spreading? Yep.

                  Is water easily accessible and carried on every fire truck and engine and available through hydrants? Also yep.

                  A lot of agencies are including car sized fire blankets as well that help smother the fire some and make burnt/burning EVs safer for tow trucks to move to a safe locations where they can be left to burn out. Sometimes for over a month! You might see fire engines literally escorting tow trucks because even with the blanket and being doused with tens of thousands of gallons, it’s still at risk of reigniting during transport.

                  The other big issue that agencies are facing with EV fires is that the water used to suppress these fires essentially becomes hazmat. So there are issues with letting it just run off into the storm system or the environment.

      • Paddzr@lemmy.world
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        6 days ago

        Anyone dealing with batteries would have. It is more common than you think and not just people being keyboard warriors.