From the MSN article linked below:
“ UK-based shipowner Zodiac Maritime has since confirmed that the fire originated in the section of the vessel carrying electric vehicles.”
Is an EV with 2% charge in the battery any more or less prone to spontaneous combustion than one with 10%, 50%, or 100% of charge?
I'm under the assumption that these are roll on/roll off carriers and that cars themselves are driven on and off (so they have some level of charge or fuel).
I know that batteries (apparently) can "just catch fire", I just don't know what the risk of fire to charge capacity of the battery is.
Higher state of charge absolutely correlates with fire danger - there are physical mechanisms in play where highly charged lithium batteries can have dentritic shorts, for example, which cause thermal runaway almost immediately.
It’s a much higher risk during charging as that is when the structures typically form, but they can also be borderline and then ‘cross the border’ suddenly when just sitting there.
It stands to reason (and simple physics/chemistry) that a fully-charged battery is going to burn more intensely than a depleted one. But as I undertstand it, Li ion batteries need a minimum "base" charge below which the battery can be damaged or become unable to be recharged (at least not by normal means). So I'd guess that like phones and other devices, they are shipped with roughly a 50% charge, allowing them to be driven on and off the ship and then on and off a truck before finally arriving at the retail dealership or other buyer's location.
Even if the EVs were not the source of the fire, they were surely the cause of the firefighting problems the coast guard had. Once ignited, EV fires are quite a thing.
The intensity of an EV is almost the same as that of an ICE car. A little bit less severe actually. There’s a study from Sweden that set an EV and ICE on fire and measures the energy/heat from the fire over time. The curves are fairly similar.
An EV battery is much less likely to catch fire from nearby car fires. A whole parking garage burned down at Sola airport in Norway, with lots of EV inside. Not a single battery pack ignited.
The challenge with EVs is thermal runaway. That can last for hours, and if you don’t cool it down the intense heat will ignite other flammable materials (plastic) in the car, or nearby cars.
It shouldn’t be too hard to make these ships EV fire proof. You just need something that can spray water on each car from beneath. That will keep thermal runway contained to a single car.
Normally you can extinguish a fire by depriving it of any of the three things fire needs. But a battery that goes up it has both fuel and oxidizer and will actually tend to react with water by getting hotter. The only solution is either isolation or massive amounts of water or other coolant.
It's not the energy of the fire, it's the difficulty in actually extinguishing it. Think of those trick birthday candles that relight themselves.
That's a misleading slight of hand. You can choke off a "normal" fire with foam and water. Can't do that with a fire that comes with its own oxidizer.
From a firefighting perspective, which is what the comment you're responding to is talking about, a battery absolutely is the bigger PITA even if there's less energy release per input. You can knock it down all day and it'll just keep coming right back up.
This is fundamentally incorrect and even a basic Google search returns:
EV and gas-powered vehicle fires pose different challenges to firefighters. EV fires are harder to extinguish due to deep-seated heat in batteries, potential for reignition, and release of flammable and toxic gases. Traditional firefighting techniques might not be sufficient, and specialized equipment like submersion tanks or specific types of foam are often needed.
Here's a more detailed breakdown:
EV Fires:
Higher Temperatures:
EV fires can burn hotter than gas-powered vehicle fires, reaching temperatures of 1,200°F or more.
Reignition:
EV batteries can reignite hours or even days after a fire, even after the flames have been extinguished.
Toxic Gases:
Burning EV batteries release flammable gases (like hydrogen and methane) and other hazardous chemicals, posing a threat to firefighters and the environment.
Difficult to Extinguish:
Traditional firefighting methods, like using water or foam, may not be effective in cooling the battery cells to the point where the fire is extinguished. Special techniques like submersion tanks or specialized foam are often required.
Prolonged Fire Suppression:
EV fires can take longer to fully suppress compared to traditional car fires.
Gas-Powered Vehicle Fires:
The point GP made was that unless the fire starts in the battery, the battery is unlikely to catch fire. Thus when an EV catches fire, as opposed to starts a fire, in the EV burns about the same as an ICE.
They even note this in the Sola fire report[1], that the EVs did not contribute anything particular compared to regular ICEs to how the fire evolved.
They even say there is so much plastic and composites in modern cars, regardless of power source, that they output twice the heat compared to old cars made mostly of metal.
I have no idea what this says. Quite literally every single English language reference returned by a simple search refutes the assertion that EV fires are not more difficult or toxic than a regular car.
The fact that EV fires are more difficult to extinguish and produce substantially more toxic byproducts than regular gasoline powered cars is well established.
Last month, a battery-storage plant went up in flames and burned for days, prompting the evacuation of more than 1,000 residents and shutting down local schools. The plant, located in Moss Landing, an unincorporated community in Monterey County, is the largest facility in the world that uses lithium-ion batteries to store energy. Residents have reported feeling ill, and many of them worry that the fire polluted the air, soil and water with toxins.
“Now you don’t see anybody walking outside because it’s terrifying, everything that’s going on,” said Esmeralda Ortiz, who had to evacuate from her home in Moss Landing after the plant began burning on Jan. 16.
> a simple search refutes the assertion that EV fires are not more difficult or toxic than a regular car
The assertion is that EV fires are not particularly more difficult than ICE vehicle fires if the battery has not entered thermal runaway.
Most EV fires do not start in the battery (at least for EVs that are not involved in a collision).
And while the battery certainly can enter thermal runaway by an external fire heating it up sufficiently, it's not a given as real-world examples like the Sola fire shows as well as various research. Here are some quotes from a paper about full-scale EV fire tests[1]:
In both cases the fire ignition took place in the rear seats. However, it has to be mentioned that in the case of the BEV, the battery was not involved in the fire for the first 800 s (full voltage in all cells of the battery).
However, the test also showed that although the vehicle had already burned for more than 10 min, the battery was still not involved in the fire and the temperature inside the battery was well below 50 °C
In the tests they forced thermal runaway after a while, by shorting the batteries.
Here's[2] another, smaller study where they tried to initiate a thermal runaway by placing a propane burner under the battery, but failed as they removed it too soon.
The burner was in place for 12 minutes, at which point the rest of the car had caught fire which also contributed to heating the battery. Yet no thermal runaway occurred.
Modern cars, EVs and ICEs alike, have more flammable material in the form of plastics than in their batteries or gas tanks[3]. And those plastics also release a lot of toxic smoke when burning. Sure, if the battery catches fire it will release nasty HF gas, but it's not like fumes from an ICE fire is healthy stuff.
For any fire, once the fire gets hot enough, it can be difficult or impossible to extinguish.
The fundamental problem is that battery fires get to be very high temperatures 1200C and cannot be extinguished at that point. I think the distinction you’re making about presence of thermal runaway or not is really rather irrelevant because yes you can put that fire out. That’s not the problem. The problem is that the devices do runaway and when they do it’s very difficult to put them out.
The ship in the original article was abandoned because it the fire could not be extinguished. The battery fire at Moss Landing could not be extinguished for 2 weeks.
Here’s a great video of the MountainView Fire Department talking about the difficulties of putting out EV fires. They explain that they’ve had cars catch on fire again 6 days later. They purchased new specialized equipment but at the time their department was one of the only fire companies that had this in California.
