A friend of mine living in an apartment complex with parking facilities at basement level recently told me that firefighters having inspected the area had come to the conclusion that they will make no attempts to go down and put out a fire if there are EVs parked. There will be fire until there is nothing more to burn, house still standing or not.
Seeing a car battery burn kind of makes me understand why.
> That's just a bad fire department. There are procedures to put out lithium-ion fires that aren't just "let it burn".
That's what they're supposed to do, though, according to Tesla[1]. The firefighters are there to pour water on the fire to cool it down and wait for the battery to burn and release its energy. This is what Tesla's manuals[1] say:
> If the high voltage battery becomes involved in fire or is bent, twisted, damaged, or breached in any way, or if you suspect that the battery is heating, use large amounts of water to cool the battery. DO NOT extinguish fire with a small amount of water. Always establish or request an additional water supply.
> Battery fires can take up to 24 hours to fully extinguish. Consider allowing the vehicle to burn while protecting exposures.
EV battery fires and their risk to firefighers are a national problem[2].
Also, you're expecting a lot from what are often volunteers who have little to no funding. I lived in a place where over $20 million was spent on police salaries each year, but firefighters and EMTs were all volunteers.
I'm one of those volunteer firefighters (Vacaville district). There's no way we would just walk away from a vehicle fire. If it means spraying water on it for hours, fine, then that's what we'll do. If there's no hydrant we'll have 2000-gallon water tenders lined up. On a big wildland fire it's not unusual for the pumpers to be working for hours.
You really underestimate how much firefighters love to use the equipment "for realz". I don't know anyone who doesn't dream of running into a (concrete) parking garage to put out a vehicle fire, EV or not.
Also, nobody (at least in my district) is allowed anywhere near a vehicle accident without bunker gear. If we had to rotate new pairs of firefighters in every 30m when the SCBAs run out, so be it. The department has a lot of tanks. We also have ventilation equipment on all the engines and squad units.
Also also: We're the rural team. The city departments (with their million dollar fire trucks) are even more hard core. "Make no attempt to put out EV fire" is just nonsense.
It can also be extremely dangerous to stay in a closed space i.e. underground parking if you don't have a way to turn off the fire. Most people don't die of fire in fires, they die of less than a minute of breathing in toxic fumes. To tell a volunteer to risk his life to watch a fire burn he can't turn off is a very privileged position to be in.
Firefighters tend to have respirators when they fight fires. It's not like things other than EVs don't release copious amounts of toxic fumes when they burn. ICEs are really not much better in that regard.
The difference is not the toxicity of the fumes, it’s the duration of the fire. A respirator will not fully protect you from a seven hour underground fire.
In an EV fire, you have an initial fire that burns hot and releases lots of fumes (a large part from all the other crap in the car combusting), and then you have a very long period where you have to dump water on the battery to keep the internal oxidation under control by cooling it. The later part is much less dangerous for the fire fighters.
This actually reinforces my point. The first part releases “lots of fumes” into a poorly ventilated underground space, which then requires firefighters to remain for “a very long period.” Your claim that the later part is less dangerous assumes that fumes have dissipated.
> That's what they're supposed to do, though, according to Tesla[1]. The firefighters are there to pour water on the fire to cool it down and wait for the battery to burn and release its energy. This is what Tesla's manuals[1] say:
No that's not what they say. They say to keep it cool to prevent it from burning. You're misinterpreting those instructions.
> besides keep water flowing over the outside of the battery pack while the inside self-oxidizes
But that is doing something other than just letting it burn. That's containing the damage, rather than letting the fire spread to everything around it.
They are different situations, but I'd argue they're different in the opposite way. For a car by itself outside, letting it burn would be fine. But in an enclosed parking garage, it's rather important to keep the fire from spreading to the rest of the garage.
Yes, but the problem with Li-Ion fire in a confined environment is that it generates a lot of toxic gas (doable but you need equipment for that), a lot of hydrogen which will react with everything near by, and the risk of explosion (in the sense of rapid fire expansion with a thermal run-away of most cells) is higher.
My guess is that the floor was poorly ventilated with complex access, rendering the access to the fire unnecessarily hazardous.
I'm not sure if that would do anything much to help; it might just trap the heat in. I think the standard recommendation for Teslas is to just dump water on it so that the extra heat energy can be conducted away and redirected in a relatively harmless way into conversion of water into steam.
>There are procedures to put out lithium-ion fires that aren't just "let it burn".
Can you provide more info on this? I'm very casual on the topic from what I've read is kind of impossible to put them out. Sometimes they have to throw the EV on a water tank and let it sit there for days.
The original poster is incorrect. The correct way to handle lithium ion battery fires is to put tons of water on them to keep them cool. Most of what's burning in lithium ion battery fires is the electrolyte being heated up by shorting batteries. You want to keep them cool so the electrolyte can't burn.
I would say that using lot of liquid CO2 must cool down a lithium fire while also denying it oxygen to continue. That's what a CO2 fire extinguisher does; it's often used to put out small fires in powered electrical installations.
At a car battery scale, especially in a garage, that would require the use of oxygen masks, and evacuating anyone around, because there won't be much to breathe. Also, of course, the fire truck must carry a large amount of liquid or solid CO2 ("dry ice").
Using liquid nitrogen would be even more efficient, but even harder to provide at scale. Liquid nitrogen is cheap, but cryogenic facilities are not.
Lithium by weight is very little of what's in the batteries. It's not Lithium that's burning. Primarily what's burning in lithium ion battery fires is the volatile electrolyte.
Sorry, that's just dumb. A lithium fire is hard to "put out", it's objectively safer than pretty much everything else that burns. It flames and sputters for a few hours, then it's done. Standard procedure for these things is to do nothing but keep it cool and wait. If your fire department can't handle that then I fear deeply for what happens in the next house fire they face.
This is just ludditism. New technology brings out a combination of people afraid of The New and people trying to look smart by pontificating about new New and Scary failure modes.
You really can't fathom why fire departments dislike stuff that can't just be put out, but needs to be kept cool for hours and hours with lot of water?
Cities have fire safety regulations for parking lots and if the parking lot violates it then it can be sealed off until fixed. It doesn't matter what's inside the parking lot unless its legal and say not a nuclear reactor.
ICE vehicles too catch fire all the time, It just seems your firefighting agency is not doing its duty.
I've been thinking that if I have a "power wall" I will want it outside a good distance from the house and in its own cinderblock bunker.
I wonder if it would make sense to install these larger batteries over concrete "basements" or pits and have mechanisms to "drop" them — maybe flood the pit with water.
You will want to do the same for synthetic clothing, cooking oil, and your cooking range & oven.
We already have houses burning down because people left the bacon unattended for a few seconds too long.
House batteries already have thermal management and fire suppression built in. Mount the battery on a brick or metal wall of your house as per the instructions and forget about the doomsday scenarios.
There's an interesting trade-off for people who go the DIY route: LFP batteries are pretty ideal for power storage, for a lot of reasons (safety, durability), but they don't deal well with cold and can't generally be charged if the temperature is below freezing. So, you can have them in the house (in the garage, perhaps) where they'll stay warm enough, or you can have them away from the house where they'll do less damage if something goes horribly wrong, but then you have to figure out how to keep them warm in the winter if freezing temperatures are a thing in your climate.
Seeing a car battery burn kind of makes me understand why.