I'm not sure, but diesel fires are definitely more of a risk to people. Fuel can quickly spread and ignite before people in the vehicle (or bystanders) have a chance to escape. Lithium battery fires are more contained because individual cells spew flame, which heats up nearby cells, which then undergo thermal runaway. This means that battery fires take longer to release their energy, which is annoying for extinguishing them, but good for anyone who needs to get out of the wreck.
There is a big difference between diesel powered engines and petrol powered engines. Diesel is much harder to ignite and this was for example big advantage for diesel powered tanks during World War II, in comparison to gasoline powered tanks.
"They introduced many innovations as they built their designs, including bell crank suspensions, as pioneers in amphibious tanks, and the use of diesel engines that were less likely to catch fire compared with gasoline tank engines that were being used at the time."
"
Diesel has a much higher flashpoint. This means the speed of deflagration is much slower. It cannot convert the diesel to vapour as quickly so can't disperse the fuel as quick to spread the surface area..
"
"
Leaking petrol is much more dangerous in an accident. It is far easier to ignite. If any leaking petrol contacts the exhaust or brake discs it could ignite causing rapid flame spread trapping people in the car. Diesel won't do this.
"
Lithium packs can light up (much) faster than you sketch here. The process you describe is correct in sequence but it takes about as long to read that sentence to get to a car that is engulfed in flame. More than one person died from the combination of toxic gases and heat before they managed to get out of the car.
Lithium Ion is a very bad battery type for anything that should be safe or moves, LFP is far better and LTO is better still.
The "I'm not sure" referred to road damage. The "definitely" referred to risk to people.
The fact that some people have died in lithium battery fires doesn't tell you if they're a greater risk than petroleum vehicle fires. Around 500 Americans die in vehicle fires every year. Last year, EVs were around 3% of vehicle miles traveled in the US, so if they're as dangerous as petroleum vehicles, we should expect 15 battery fire deaths in 2025. The actual number seems to be 2 or 3.
Diesel fires are put out much faster than battery fires especially when the battery is huge and fully charged. Battery fires are also much hotter, up to 1000 C (~1800 F), metal fires are no joke.
Diesel damages the asphalt more in different ways. It attacks the binder in the asphalt and softens it up (after all they are both byproducts of the same crude oil precursor and just want to recombine). This process takes even days so if the cleanup is fast there's minimal damage. Most of the fuel that doesn't burn runs to the side of the road anyway.
Lithium battery energy density is much lower than petroleum, so the difference between a fully charged 100kWh battery (which weighs over half a ton) and an empty one is less than 3 gallons of diesel. Most of the energy expended in a battery fire is from the electrolyte reacting with the cathode material.
Over/under-charged batteries are a safety hazard because they can generate hydrogen gas which can initiate a fire, but the energy released from the fire will be pretty much the same.
The energy released during a fire is higher than what is accessible by discharging the battery. Here's one paper describing ratios from 1.25 to 5 depending on access to oxygen during the combustion.
Honestly no idea. But after receiving multiple fire trainings and talking to trained firemen, I have to say that all else being equal (and gun to the head because I actually want neither) I'll take a diesel fire over a battery fire any day.
A lot of dangerous fumes come from the other material burning around the source. And at 1000C plenty of neighboring stuff decides to burn.
Depends on context and the location of the road surface and the nature of the explosion.
https://www.sfgate.com/bayarea/article/Tanker-fire-destroys-...
(Also, the rebuilding was epic, the only time I've seen the state and a contractor move quickly: https://longreads.com/2024/07/15/rebuilding-the-maze/ )
That's gasoline. Diesel doesn't explode.
I interpreted the question more broadly, replacing "diesel" with "fuel".
I'm not sure, but diesel fires are definitely more of a risk to people. Fuel can quickly spread and ignite before people in the vehicle (or bystanders) have a chance to escape. Lithium battery fires are more contained because individual cells spew flame, which heats up nearby cells, which then undergo thermal runaway. This means that battery fires take longer to release their energy, which is annoying for extinguishing them, but good for anyone who needs to get out of the wreck.
There is a big difference between diesel powered engines and petrol powered engines. Diesel is much harder to ignite and this was for example big advantage for diesel powered tanks during World War II, in comparison to gasoline powered tanks.
"They introduced many innovations as they built their designs, including bell crank suspensions, as pioneers in amphibious tanks, and the use of diesel engines that were less likely to catch fire compared with gasoline tank engines that were being used at the time."
https://en.wikipedia.org/wiki/Tanks_in_World_War_II
The answer from an actual firefighter:
" Diesel has a much higher flashpoint. This means the speed of deflagration is much slower. It cannot convert the diesel to vapour as quickly so can't disperse the fuel as quick to spread the surface area.. "
" Leaking petrol is much more dangerous in an accident. It is far easier to ignite. If any leaking petrol contacts the exhaust or brake discs it could ignite causing rapid flame spread trapping people in the car. Diesel won't do this. "
https://www.quora.com/Is-it-possible-for-diesel-cars-to-expl...
> I'm not sure
> definitely
If you're not sure, why the definitely?
Lithium packs can light up (much) faster than you sketch here. The process you describe is correct in sequence but it takes about as long to read that sentence to get to a car that is engulfed in flame. More than one person died from the combination of toxic gases and heat before they managed to get out of the car.
Lithium Ion is a very bad battery type for anything that should be safe or moves, LFP is far better and LTO is better still.
The "I'm not sure" referred to road damage. The "definitely" referred to risk to people.
The fact that some people have died in lithium battery fires doesn't tell you if they're a greater risk than petroleum vehicle fires. Around 500 Americans die in vehicle fires every year. Last year, EVs were around 3% of vehicle miles traveled in the US, so if they're as dangerous as petroleum vehicles, we should expect 15 battery fire deaths in 2025. The actual number seems to be 2 or 3.
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> If you're not sure, why the definitely?
They said "I'm not sure" to the road surface question, and "definitely more of a risk to people".
Roads and people are different things.
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Regular cars usually burn out in 30 mins or less. It's a fair assumption that a 10-15 hour fire would be more damaging.
I’d think it really depends on the heat and proximity to the road
If a battery pack burn less hot and sits higher off the roadway, I can see it being less damaging
Diesel fires are put out much faster than battery fires especially when the battery is huge and fully charged. Battery fires are also much hotter, up to 1000 C (~1800 F), metal fires are no joke.
Diesel damages the asphalt more in different ways. It attacks the binder in the asphalt and softens it up (after all they are both byproducts of the same crude oil precursor and just want to recombine). This process takes even days so if the cleanup is fast there's minimal damage. Most of the fuel that doesn't burn runs to the side of the road anyway.
> especially when the battery is huge and fully charged.
Huh, TIL: https://link.springer.com/article/10.1007/s10973-018-7899-y
Lithium battery energy density is much lower than petroleum, so the difference between a fully charged 100kWh battery (which weighs over half a ton) and an empty one is less than 3 gallons of diesel. Most of the energy expended in a battery fire is from the electrolyte reacting with the cathode material.
Over/under-charged batteries are a safety hazard because they can generate hydrogen gas which can initiate a fire, but the energy released from the fire will be pretty much the same.
The energy released during a fire is higher than what is accessible by discharging the battery. Here's one paper describing ratios from 1.25 to 5 depending on access to oxygen during the combustion.
https://cea.hal.science/cea-05234204v1/document
Lithium fires are brutal, they're extremely fast and the toxic gases are just as dangerous as the fire itself:
https://www.reuters.com/world/asia-pacific/about-20-bodies-f...
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Which fumes are worse, from EVs or diesel filers?
You don't want to breathe either, but the answer generally is battery fires which can produce extremely toxic gas like hydrogen flouride
https://m.youtube.com/watch?v=lADLvwAJs-c
https://en.wikipedia.org/wiki/Hydrogen_fluoride
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Honestly no idea. But after receiving multiple fire trainings and talking to trained firemen, I have to say that all else being equal (and gun to the head because I actually want neither) I'll take a diesel fire over a battery fire any day.
A lot of dangerous fumes come from the other material burning around the source. And at 1000C plenty of neighboring stuff decides to burn.
Lithium fuel can melt asphalt seams
Yes
how?
You can't use a fire extinguisher for one to put it down. Li-Ion effectively self-sustain when ignited.
The only version of putting it down is letting it burn out.
Morealso diesel is hard to ignite on its own, hence the ICE use compression not spark
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Yes, but you can leave satisfied knowing no fossil fuels were burned in the creation of said fire.