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Comment by jdietrich | Hacker News Reader

Between 2006 and 1010, an average of 152,280 passenger cars caught fire per year, causing an average of 209 deaths and $538m in damages.

https://www.nfpa.org/-/media/Files/News-and-Research/Fire-st...

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I do believe the media tends to make too big a deal of EV fires and issues (given how they compare to gas cars' frequent issues). That being said, I don't think the stats you shared are at all relevant here: those stats are probably almost all from accidents and maintenance issues on the road involving moving/operational vehicles. The explosion in this story was from a stationary vehicle parked in a garage, allegedly not even charging.

There are probably some rare cases of this happening on gas vehicles over the years, but I expect any such case would also be concerning and deserving of a deep investigation.

BMW seems to have such an issue with its gas cars. Or at least evidence indicates this is a possibility:

https://abcnews.go.com/Business/bmw-mystery-fires-abc-news-i...

Quite a few manufacturers had similar streaks over the last few decades that usually ended in changes to the car line in question, another example to yours is [1]. Not sure why we treat this differently (either by exaggerating or ignoring cases where an EV is involved).

It's certainly a thing that happens in these systems, sometimes it happens enough to warrant changes and/or recalls if it's systemic. Should there be insufficient protection in EV models that fails to address the safety issues unique to the new components that's something we need to address, just like we address when it happens in traditional cars.

Media over-reporting this is no different than those "look at that expensive supercar on fire" cases imho, the tech is new and gets clicks, slap Tesla in the summary and you get even more clicks. We certainly don't help the issue with discussions that look like programming language wars.

[1] https://www.cnet.com/roadshow/news/ferrari-fuel-vapor-leak-f...

*Edit: changed to real link from amp version.

Happened with an ICE to a neighbor house this past week.

Yes, you'd be correct, there is one case of exactly that happening to an ICE car, with the overall insurance claim being so great ($100M+) that the US justice department has decided to take the case on themselves. It's absolutely crazy.

https://www.google.com/amp/s/jalopnik.com/how-one-suv-fire-d...

Interesting story, and that fire certainly happened in the worst possible spot, but it's far from the only ICE car fire ever.

Wow, that is just fascinating, you should submit that link as a new post.

https://news.ycombinator.com/item?id=20673550

When working late in DC - I recall looking across the street a parked car fire. The amazing thing was by 5 am ( fire started at 4am) there was virtually no sign of the fire... sharing this because I think it’s not too uncommon for parked ice cars to catch fire

Parked gasoline cars catching fire is very common. I know of two cases personally of well maintained, supposedly good quality cars that burned down after parking. There's a lot of heat left over in a car that's been running for a while.

I guess this all comes down to proportion, i.e. how many IC engine on the road that caught fire verse the total number of IC engine production.

My best friend growing up had his car burn to the ground in front of his house. He came home from work, parked out front, and 10 minutes later his car was fully involved. This was 20 years ago. There was no news coverage.

There are probably some rare cases of this happening on gas vehicles over the years

Unfortunately, the majority of cases I remember were due to flaws in the electrical system:

https://www.autosafety.org/ford-ignition-switch-fires/

https://www.autosafety.org/category/vehicle_fires/ford_cruis...

https://www.autonews.com/regulation-safety/ford-recalls-f-15...

https://www.usatoday.com/story/money/cars/2014/08/07/gm-reca...

In other words, the (relatively small) battery in ICE vehicles provided the initial energy to start those fires, and not the fuel itself. I suppose one could say that a safety advantage of ICE vehicles when parked and off is that even a fuel leak requires a source of ignition to cause a fire (also, diesel is very difficult to actually ignite), whereas with an EV there is always a huge source of electrical energy available and a lot more components which are always supplied with power.

My guess is that once they become as common as ICE, EVs will continue to catch fire at roughly the same rate if not more.

You're wrong. Consider the literally billions of batteries out there every day not catching fire.

EV fires will be fewer.

The propulsion battery in most electric cars (certainly Teslas) is disconnected by a relay when the car is off. So the amount of powered stuff isn't any higher than gas cars. Teslas also have a 12V battery to bootstrap the system and run accessories when the main power is off, though it's smaller than a typical ICE battery because it doesn't have to crank an engine.

I don't think you can predict from theory which will have higher fire rates. All the fires are due to small flaws in the details, so it's a question of design and manufacturing carefulness.

>when the car is off

Does it count as "off" when the car periodically wakes up when parked to do everything from check for updates to warming/cooling the batteries or cabin?

(Not trolling, I can't find the actual answer.)

Nope. My car can drain the HV battery via recording video etc.

It's certainly not solely powered by the 12V as it'd be flat within the day.

Also, if the little 12-volt runs down, will it recharge itself from the main one?

Yes.

I can only speak for the Leaf, but much like a petrol/gasoline car, the 12V battery is only charged when the car is on (and when the car is actively being charged). It is entirely possible to run down the 12V battery if you leave the car parked long enough without it being turned on. Once the 12V runs down far enough, you are no longer able to turn the car on (or charge it) as the 12V powers the contactors for the main battery. I have had to jump start my Leaf due to a bad 12V battery.

In the case of Teslas, yes. The power drain on the 12V system when parked from all the computers etc is apparently so high that they have to recharge it periodically from the main battery. The service life of the 12V battery is pretty terrible because of this. They also have battery heaters that switch on periodically to keep the main battery warm, which I think are powered by the main battery. Basically, if you leave your Tesla sitting in a garage for a few days you can expect the main battery to be connected and used at least some of that time (maybe all of it) even though it has a contactor to disconnect it entirely.

It happens fairly routinely. Google "car fire in garage" for numerous examples. One particularly amusing one: https://abc7chicago.com/17-cars-catch-fire-at-newark-airport...

You have a complex electrical system that gets constantly temperature cycled in a fairly extreme way, sitting right next to a bunch of flammable material. Not a big surprise that it goes wrong sometimes.

I doubt it's common enough to be a real worry in either type of car, though.

>I doubt it's common enough to be a real worry in either type of car, though.

People need to keep statistics in mind when looking at these issues because there are lots of people who are heavily invested in EVs failing. That first tweet in the article is a prime example. They frame a single incident of a fire with a Hyundai EV as negative news for Tesla. You can click through to that account's feed and see they tweet almost nothing but negative comments about Tesla. People like that are actively working to make sure that you see every single isolated incident when something goes wrong with an EV in hopes that it stalls that industry.

And just a disclaimer to the above comment, this incident should definitely still be investigated to make sure there isn't a widespread issue. It is just a reminder that we shouldn't overreact every time a single EV has a problem because odds are we would never even hear about it if the same thing happened to an ICE vehicle.

That tweet tags $TSLAQ, which is a group of Tesla short sellers working toward the company’s failure.

> and maintenance issues on the road involving moving/operational vehicles.

I'm moved to share about being very careful when opening the hood (engine compartment cover) of a vehicle that's overheated. I did that once, and there was a flash fire. From oil and grease on the engine. Fortunately I didn't get burned. And closing the hood put out the fire.

But damn, it was a shock.

How many of those were sitting in a garage or just parked, doing nothing, when they caught fire?

A not insubstantial amount, I'd predict.

(Anecdata) I had to prove that the work I did on a car (replacing the bumper) didn't cause a fire which burned down the garage and house it was in a week later.

That said, I do agree with your point that a brand new vehicle should not have these sorts of issues. Be interesting to see where the cause lay.

I'm not sure about brand new vehicles. Cars have a bathtub curve like anything else. I expect car fires are mostly very old or very new cars.

The burden of proof ought to be the opposite.

Just wondering but would insurance cover you in either case?

And how many of those explode with enough force to send a garage door flying?

Large explosions from gasoline powered cars are indeed rare, but it's not uncommon for car fires to result in a number of smaller explosions that can be just as deadly, as pneumatic cylinders that operate a lot of hood and tailgate supports cook off an launch the rod inside out like a projectile.

Another fun failure mode of gas cars is that when the gas tank does finally fail, if the car is on any sort of a slope, you now have a stream of flaming gasoline to worry about...

I mean you need to compare that to a lithium fire which is its own kind of awful to deal with.

The reality is that current lithium batteries do have a very energetic failure mode - it’s not particularly common (because they’re engineered in such a way that a battery failure doesn’t trigger a fault in the casing) but when it does happen the immediate explosive force is much greater than for a gas tank. Also because physics lithium batteries do have a greater potential to simply “go wrong” when not in active use.

That said it is obvious electric cars are the future - I just hope we can do better than the current battery tech, the power density is way down on gasoline and that means the batteries are huge, and therefore weigh enough to impact overall car efficiency.

Sure, my point is just that gasoline isn't all sunshine and rainbows.

Large energy capacity batteries, and lithium specifically, definitely pose some new and "interesting" challenges. I'm optimistic though. Gas tanks are as safe as they are today because of several decades of safety-focused engineering and iteration.

If you gave me a choice between an ICE or an EV fire, I'm absolutely going to choose the gasoline, but that's just because it's a very mature technology, with well understood practices for dealing with them. I'd be surprised if I have the same answer in 10 years time though.

This is a very real threat albeit generally rare, of course.

As long as an electrical circuit has power it can begin to heat up wires or connectors due to bad contacts or worn threads, for example, even if the car is cold and has been sitting for days. In the lucky case there's a slow short that just drains the battery or burns out the wiring, stopping the generation of more heat. In the worst case the heat will melt something and provide a new, direct short to ground, which runs enough power through the wires to ignite something.

I have a garage for doing repairs and maintenance on my cars. Each time I park one of my vehicles (new or old) there I'll disconnect the battery negative cable and keep it disconnected unless I have to start the engine or connect to diagnostics. I have insurance, of course, but the idea of my shop burning down alone is enough of a deterrent that motivates me to do the small effort of disconnecting the battery. I really don't want to rebuild my shop and reacquire all my equipment because of a bad connector hidden inside the wiring harness somewhere in my car chose to fail.

How many of those were the latest model year, purchased less than 6 months prior?

The 2010-ish model Jeeps had a habit of doing exactly that. Here's a video showing a bunch of similar catastrophic fires in Jeep Wranglers occurring without any sort of collision. And of course Chrysler's special investigators almost always just hand waved away the defects as not their problem and not a defect with the vehicle.

https://www.youtube.com/watch?v=iyEaC9xcYhE

Vehicle fires unrelated to a crash are not unheard of for traditional gas powered cars.

I guess a gas-filled vehicle is just as capable of blowing the roofs off a garage too.

If you park it in an unventilated space like that and then leak gasoline all over the place to evaporate until it reaches an ignition source? Yeah.

https://www.gainesville.com/article/LK/20090702/News/6041531...

https://www.firehouse.com/home/news/10515159/one-killed-in-c...

> Between 2006 and 1010, an average of 152,280 passenger cars caught fire

IIRC 300 people a year are killed by car fires in the States while self-filling gas cars due to static electric sparks from their clothing, and/ or shoes off the cars carpeting. Nasty that, huh?

I wonder how many of those were caused by animals though, shorting out wires or creating nests in areas that then catch fire.

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