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Comment by philwelch | Hacker News Reader

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philwelch

I’ve never heard of a gas tank spontaneously bursting into flames.

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https://www.nbcnews.com/business/autos/bmw-adds-nearly-185-0...

"BMW is adding nearly 185,000 vehicles to a 2017 recall for possible engine fires.

Two years ago the company recommended that the vehicles be parked outdoors until problems are fixed."

Now you have heard.

"engine fires..." not gas tanks.

Given gas cans often need a flame arrestor to keep the same happening from gas stored in garages, and that often wasn't included in cheap versions but was in commercial versions for many decades, my guess is that it happened and might still happen.

80’s television taught me that virtually every rollover accident will result in a vehicle explosion.

There are about 160,000 fires involving personal internal combustion engine vehicles per year.

I think the key word there was "spontaneous", along with the relative danger and difficulty of dealing with them. An EV fire can take 24 hours to secure. A gasoline car takes about 300 gallons of water.

I'm not saying EV fires are a bigger issue than gasoline cars. I'm saying that you cannot look merely at incident rate to determine the issue.

I would say that's an advantage for EVs. I'd rather have fires that are slow to start and slow to put out than the opposite.

I’m not sure, it’s 24 hours of constant monitoring and fire suppression from a trained fire crew. Not something that’s scalable.

How many of those are due to the ICE? In my experience most vehicle fires are electrical in nature, whether it's an EV or not (the 12v system in an ICE car can still cause a fire).

Ethanol gasoline degrades older vehicle's rubber fuel lines, This has lead to many fuel fires.

Yeah, I'm not saying it doesn't happen, I'm just saying it's very infrequent in my experience (~15 years as a firefighter). Electrical issues, accidental fires in the passenger compartment (cigarettes/joints igniting trash in the footwell), and even arson are all far more common than fuel system issues.

So, there’s a guaranteed recipe for starting an engine fire (though from oil, not gasoline): Icy hill, and idiot drivers holding their engine at max revs for a few minutes to try and conquer them. The heat destroys the seals, oil leaks out, and combusts on the hot block.

Which makes me wonder, how would an EV handle the same poor driving conditions?

I think you'd just heat up the battery pack until the cooling system couldn't keep up, and then it would automatically limit the output to prevent the battery from overheating. Apparently racing tesla's on tracks has the same thing happen.

It's not obvious to me how you could cause an ev to fail catastrophically like that, because they do have sensors to detect overheating in the battery. I guess in theory you could also do something like catch the tires on fire from too much friction...

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