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.
Our town had to use an excavator and dozer to bury a Tesla car because it wouldn’t stop burning.
I read in a firefighter’s thread that the trick is to use a low pressure spray directly on the battery compartment. (It was a thread about Tesla cars not semis though so that might not apply)
The reason was you can’t actually put the fire out, it’s self oxidizing (it can literally burn underwater) so you basically need to wait till it burns itself out. Fortunately batteries only hold something like 1/10th the energy of gasoline and can’t release that energy as quickly so a fine light spray is enough to keep it from getting hot enough to catch anything else on fire including batteries in the surrounding battery modules.
Takes a long time, like hours to get it to a point they can move the vehicle and literally a couple weeks before the reaction completely fizzles out. They have special lots they tow them to where the car can fizzle itself out without damaging anything surrounding it.
Is water the best choice for a chemical fire?
Maybe. Water is cheap, available in quantity, and non-polluting. Since a battery fire is self-oxygenating, I don’t think putting it out is something you expect. All you can do is take away the heat both to contain the damage and to eventually stop the reaction.
I don’t think so, but what else are you gonna do? Can’t really submerge it in foam at a moments notice like you’re supposed to
The nords figured out you can put it out immersing it in salt water. Pretty self explanatory.
How much is this in Capri Suns?
950,000 Capri Suns
(200ml per Capri sun, 5 Capri sun per litre, 190,000 litres water)
But it would take a long time to open each packet and spray it on the fire.
But it would take a long time to open each packet and spray it on the fire.
- Lay the Capri Suns in the ground next to the fire
- Get another semi truck
- Drive over the packets to squish out the liquid onto the fire
- If the additional semi truck catches fire as well, repeat from step 1
There’s 5 200ml Capri Suns to a liter. At about 190,000 liters, we’re looking at about 950,000 Capri Suns.
I went through “Bedrijfshulpverlening” (Dutch, if you want to run it through translate just in case I mess up the correct translation). I guess it’s business first responder or something.
When we were attending the fire training part and we were teached about fires, someone asked “what if there is a car fire”. They said: “starting petrol car fires can be extinguished with a portable extinguisher if you are lucky. But electric car fires, leave them alone. They seal the cars in special water-filled containers and leave them alone for two weeks. There are reports that even after the two weeks, when the car was retrieved from the water, the fire started again on it’s own. Firefighters really hate electric vehicles”.
Lithium is a metal right? Putting water on a metal fire usually just makes the fire worse.
Lithium isn’t just a metal it’s a metal that has a rapid exothermic reaction with water. Or at least that’s what I remember my high school Chem teacher saying.
That’s when it’s not even on fire, right? Like pure sodium or aluminium (I forget which one combusts in water and which was just the air)?
You are right, but in the case of a Lithium battery fire the strategy is to use the large thermal capacity of water to cool the battery until the reaction is done.
I just remembered i can even name myself as a source when i fucked up and punctured my phone battery while disassembling it (those dumbasses used large amounts of adhesives to mount the battery and i wasn’t careful enough). I simply dropped it into a bucket of water and waited it out.
business first responder
"alright, is everyone here? this is an all-hands meeting. Where is Joey? Is he in the bathroom again? He’s missed the last 3 meetings… Anyway. Top of the agenda, there’s apparently a fire, right over there. Fires are kinda hot and so we have been sure to stay a good distance away, as to not raise the temperature of everyone’s complimentary bottled water, handed out at this meeting.
Now it says here that we should tackle this situation as quickly as possible. Has anyone run the numbers by the finance team? We don’t want to spend too much on this. The big-wigs upstairs never think about the big picture, and really I don’t see why one fire is worth pivoting all our available resources. Samantha, yes?"
“Sir, the fire is growing at an alarming rate, shouldn’t we just postpone the meeting and focus on the fire?”
“See, that’s exactly the kind of thinking the execs have. But if we spend all our resources, cuts will be made, and jobs will be lost. Not mine, of course, but others. Did anyone do a PR analysis on us ‘putting out this fire’ versus just running a week-long ‘we are sorry’ ad campaign?”
(lol I just got the thought and ran with it)
How much water does it normally take to put out a semi fire? Say a tire fire, engine fire, or the entire contents of a semi in flames? I couldn’t find the answer googling, but I did find that combustion engine semis burn at the rate of 7000 per year.
https://plattner-verderame.com/blog/the-dangers-of-truck-fires/
I don’t even think this is the right metric to use.
You aren’t putting a lithium battery fire out with water. You’re just keeping it at bay until the energy is all used up. The more energy, the longer it’ll take.
We might need new ways to deal with these fires, but it’s not like we can completely submerge a semi in water.
I wonder how encasing the object in a fire retardant foam would behave, although we gotta think about the toxicity of that too.
Edit: I wonder if you could even calculate the amount of water you’d need to hold it off upfront based off the battery size and current charge.
There’s already tools to deal with lithium fires, class D fire extinguishers, sand and vermiculite. When I worked heavily with lithium non-rechargables we had lithium disaster plans for fires, explicitly in that was alerting fire fighters that it’s a combustible metal fire so they can react accordingly, those fires need to be smothered afaik, water was a big no no.
Generally though, the plan was, escape and enforce a quarantine zone because primary cells give off nasty stuff, if you can drop it in a bucket of vermiculite if it’s out of the containment vessels and pretty much let them do their thing. Then once it seems like it’s done, wait more time to make sure it’s actually safe with 30 minute gas tests, then package them for safe transport.
The problem though is how do you do that in the middle of nowhere on the highway like in this case? We need something big enough and portable enough. They clearly didn’t have that for this fire.