this post was submitted on 06 Sep 2023
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Except you totally would. If you punctured a gas tank, it'll get gasoline on hot components that'll cause it to ignite.
Do you think the gas tank is IN the engine bay or something? The hottest thing underneath a gas tank might be the exhaust... The ignition temp of gas is something like 500F/260C... Without spark... it's not going to happen just out of the blue. An Exhaust CAN get that hot.. But under most normal uses, basically all normal cars won't get that hot (racecars and other "performance cars" probably will get hotter than the ignition temp of Gasoline).
I was thinking in terms of a crash or a huge object intrusion. That'll be pushing all sorts of things to places they're not supposed to go, such as hot break pads or even parts of the other car.
Just like in normal operation you wouldn't be able to catch a gas tank on fire by puncturing it, you wouldn't get a puncture on a battery either in normal operation. It's the extreme crash scenarios you need to worry about. Both batteries and gasoline are very energy dense and potentially dangerous. And both have a lot of mitigation strategies to keep them from being a hazard. Batteries aren't inherently lots more dangerous like the original comment seemed to be implying.
Batteries at this point are almost universally the base of the car... It's not hard for debris on the road to kick up and puncture the underside of a car.
A fuel tank would simply leak it all out... Unless there was a spark. A battery cell being exposed to air will self-immolate. It all depends on how it's packaged... Which we're learning in the Florida hurricane here... They're not that well packaged...
That's why they have a thick belly pan. It's all mitigation.
There is nothing hot under the gas tank. Just the exhaust, which is not hot enough to ignite the gas. Also, the car in the picture seems like it was stationary. Please tell me, how anything in a combustion engine vehicle could be hot enough after about an hour.
No.
I've worked on too many crappy old cars to belive this. First of all, the gas tank is on the other end of the car from the engine unless you're driving a Trabant. It's possible to have a fuel line rupture in the engine bay, but if that happens basically every gas or diesel car has this magical thing that happens - turn the key off, and the fuel pump stops running, so you're not spraying an entire gas tank on a fire. If the gas tank itself is punctured, you don't get a fire unless you're literally lying under it with a lit match.
I've had two motorcycles break a fuel line while running, and one of them had a gravity fed fuel system - so the gas DID keep flowing out of the tank. It didn't catch fire, and I only noticed when the engine stopped. Another one DID catchtank, when the gas spilled on the hot exhaust (and it was a 24 year old bike, not a nearly new Tesla) and I put it out with the contents of an outdoor ash tray. (sand and rainwater)
So gas won't ignite when you puncture the tank without an ignition source. But stick an ice pick (or part of the car you've hit) through the battery, and it will light off on its own. I want more EVs, I'd like one myself, but people like you posting easily disprovable things about EVs just look silly and hold everyone back.