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Yes, but an important part of that context is that electric car fires also burn longer and hotter and take significantly more effort to put out. Too little water can actually make the fire worse.

Annecdotally, my recollection from other articles is that electric cars do in fact catch on fire less often. But it also seems like they may be more difficult to deal with. This may change as EV's become more mainstream & fire departments adapt: Graphite may be effective in putting out these fires, and maybe it will become a common tool in fire departments.

For the time being, rare or not, they post a much larger problem to deal with when they do occur.



Yep. Moreover, the issue isn't new cars today.

You know when you saw that old Chrysler Grand Caravan burning on the side of the road, and you hear the story that the person has been holding it together solely with thoughts and prayers and maybe $500 between tires and oil for the last 7 years of its 19 year life?

That's the current inevitability. I'm not worried about someone's 6-month old Bolt or 2-year old Model 3. The issue is when we're eventually talking about a 22-year old Model 3 that's had 13 years of deferred maintenance, is totally clapped out, and is only on the road because someone paid some mechanic off to look the other way during a state vehicle inspection for the past 5 years.

Germany is starting to standardize on towing an electric car away to dunk it in a tank to ultimately handle fires.


> and is only on the road because someone paid some mechanic off to look the other way during a state vehicle inspection for the past 5 years.

Making mechanics liable - maybe jointly as a business and an individual - for their failure to inspect vehicles properly would be a pretty simple mechanic to reduce this risk.


These inspections are nothing but pointless revenue generation for the state, checking for the check engine light and inspecting 1 wheel at most usually. Lots of states don't even have them.


In Germany they are very serious about vehicle inspections, and insurance requirements.


Didn't the big German auto manufacturers literally develop the hacks to bypass diesel emissions inspections? I'm not sure I'd hold anyone up in a pedestal on this score...


Those cars still passed the inspection. Which means they were physically sound. A battery isn't going to shift into an alternate mode where it becomes a spontaneous fire hazard.


Those have nothing to do with each other: Germany indeed has a company level corruption problem (especially in combination with the conservative party), but pretty low corruption at the citizen level, i.e. where vehicle inspections happen.


They got caught.


Not by any German regulator or agency.


That sounds more like an argument for effective inspections being universally required more than anything else? Apologies if I've misinterpreted.


We get by fine without rigorous inspections, and they amount to a regressive tax like a lot of other fees related to keeping a car.


Death by burning from an exploding battery from an uninspected, poorly-mainteained car in the garage of your shared low-rent apartment building is also a regressive tax.

I'll take the inspections.


It's not like states without inspections have an endemic of exploding cars as it is. I don't think the justification for inspections is really there.


Fuel-based cars tend to burn after an extreme adverse event, usually a collision.

Battery fires are more frequently spontaneous, or occur during charging.

How many barbequed children do you find an acceptable number?


Battery fires usually happen after collisions too. Fires while charging are rare but they grab headlines because they're novel.

I think trying to use inspections to solve that is a case of barking up a really stupid tree. In the case of EV charging fires there's not really much a mechanic can inspect that some electronics cobbled onto the pack couldn't. In the case of battery pack damage an annual inspection isn't going to do much good since most of those cases will cause problems before that or not at all.


"Parked Teslas Keep Catching on Fire Randomly, And There's No Recall In Sight"

https://www.thedrive.com/news/28420/parked-teslas-keep-catch...

Article list 9 cases. None involved accidents. Several were during charging, one during transport (on a flatbed truck).

All are of


In Ireland, roughly half of the vehicles going for the NCT fail on the first try, and ultimately about 5% don’t pass at all after retries.

Of that, I’d say half of the initial failures are simple things that don’t require a mechanic, (dead bulbs, bad/low tires) and the rest require a me hanic to do something.


My state has inspections, but does not charge for them.


If it’s a Chrysler product it doesn’t need thoughts prayers or old age to spontaneously combust. A brand new one will sometimes so it all on its own due to bad design


Some countries have mandatory regular inspections for critical vehicle functionality like brakes. We will probably require EV battery checks like this as well, if the BMS / firmware is not enough to keep the battery pack safe.


Safety inspections are close to worthless for safety on a macro level (they are great if you own a BHPH dealer or are a government regulator trying to give shops a reason not to fudge emissions inspections though).

You implement mild inspection laws and they do nothing because people can just pay the fine or whatever.

You implement invasive inspections where people are rich and they do nothing because rich people already don't drive on bald tires and whatnot.

You implement invasive inspections where people are poor and you create incentives to circumvent the law and hardship among those who don't ignore the law.

Mechanical failure is a negligible cause of accidents and injury so applying lots of effort co chase something that's only a source of the minority of problems is kind of a fools errand to throw a ton of societal resources at it.

If inspections really make the roads safer it would be an insurance thing and you'd see differences in premiums that reflect differences in law, insurers setting up their own programs where none exist and lobbying states for inspection programs. You basically never even hear a peep out of them about safety inspections unless it's in the context of getting people to upgrade to a newer car with better safety tech. Contrast with intoxication, distraction and driver training which are issues that insurers and their lobbyists constantly weigh in on.


GP covered that: "(...) and is only on the road because someone paid some mechanic off to look the other way during a state vehicle inspection for the past 5 years".


> Germany is starting to standardize on towing an electric car away to dunk it in a tank to ultimately handle fires.

I suppose if the problem is widespread enough, every city will have a mobile dunk truck at the ready for electric vehicle fires.


And what do you do if those fires cause other things to burn in the vicinity?


Same thing you do when an ICE car sets a building on fire. Apply water and put it out.


Except for an ICE you only need to dump about 300 gallons on it. For an EV, it can take 24 hours to get the thing fully dealt with.


That's only relevant for the EV itself, not for the stuff it lit on fire.


You put out the fire, then dunk the EV in a tank when it's out to keep it from reigniting, while not having to monitor it.


Bring the regular truck filled with water to hose it down.


Not if, when.


This is yet another good reason to decouple the battery from the rest of the vehicle. Hit the emergency release, battery drops out of the car, and push the rest of the vehicle away.


I kind of hope that gets to be an (infrequent) problem.

As it is, I've lately been wondering about what happens to 14 year-old electric cars with dead batteries that cost more than the car is worth.


People like me buy them for $500 and put the motor in a grass kart


I had no idea what a 'grass kart' was, so I looked it up.

Cool stuff! And thanks for repurposing the motors.


Towing the car in a tank seems a sensible solution, but I'm wondering if it wouldn't be simpler to tow the tank near the vehicle, lift it and dunk it there?


It could be hard to get a car up into the tank... connecting a winch might not be possible due to the heat, but I wonder how they get around that to tow it?

Also, needing to plan for larger vehicles like a pickup truck would mean > 4,000 lbs of water to submerge one, base an approximate dimensions of such trucks & the corresponding volume of water.

Than again with batteries generally in the bottom of the car, maybe you'd only need to submerge a few feet?

I can definitely see the need for new emergency response equipment in the EV future.


> It could be hard to get a car up into the tank... connecting a winch might not be possible due to the heat, but I wonder how they get around that to tow it?

Seems like something similar in design to this would do the trick, maybe with sufficiently thick steel plating on the side:

https://www.youtube.com/watch?v=GaYN6yC4bnI


> The issue is when we're eventually talking about a 22-year old Model 3 that's had 13 years of deferred maintenance, is totally clapped out, and is only on the road because someone paid some mechanic off to look the other way during a state vehicle inspection for the past 5 years.

Except that the 22 year Model 3 also has a computer inside the battery that should be keeping things in check. Assuming the battery can even hold any charge at that age.


And said computer was likely receiving software updates and sending telemetry for most, if not all, of that time.


Or it have been hacked either to send fake data or no data at all... Knowing the general level of security in industry and even with some high end smartphones, I expect it to happen.


For everyone interested, there is an interesting study to be found researching EV vs gas driven car fires [1].

"Nevertheless, existing test results have revealed that the heat release rate of EV fire is comparable to that of the fossil-fuelled vehicle fire, while EV fire may release more toxic gasses like HF from burning Li-ion batteries."

[1] https://www.researchgate.net/publication/338542510_A_Review_...


> For the time being, rare or not, they post a much larger problem to deal with when they do occur.

It seems to me that being harder to put off but occurring less frequently, and most importantly not exploding (leaving significant amount of time for occupants to get out, if they are able) is a pretty good trade off.


Also a gasoline car actually exploding is exceedingly rare. It generally takes a bit of effort to get gasoline to explode, rather than simply catch on fire. The tiny explosions that occur in the engine are only possibly due to gasoline being aerosolized into a fine mist.

Take a gas can with a soaked rag & trail of gasoline leading to it & set it on fire and you'll have quite a fire on your hands, but no explosion. Now, add a tiny bit a black powder to the equation to disperse the flaming gasoline into the air and you've got a small fuel-air bomb on your hands. But that-- or similarly explosive circumstances-- just don't happen with cars much at all. Pop culture, where a few guns shots result in an explosion, gives the wrong impression here.


For the curious: The Mythbusters actually tested the "shooting a gun at a gas tank explodes the car" thing, and it didn't work. It only worked when they tried it with tracers, but those are a whole different thing than ordinary ammo.

I couldn't find a clip of it, but here's the Mythbusters Wiki page for the episode: https://mythbusters.fandom.com/wiki/Car_Capers


Don't try this at home though


It could be a good trade off, it depends on more details though. Do electric car fires flame up faster, giving passengers less time to exit the car? What about toxic fumes emanating from the burning batteries? Since they they burn hotter and for much longer, are they more likely to damage surrounding infrastructure, like a bridge, before being extinguished?

I don't know the answer to these questions. They could all be "no". But before judging the trade off those are important factors to understand.


I don’t know about giving occupants more time to get out. I have seen the carpark video of a Tesla going up in flames in China.

https://www.bloomberg.com/news/videos/2019-04-22/tesla-inves...

Thing went from 0 to 110 real quick.


From an exterior perspective of a parked car certainly that would look like the case. The interior software in an operating Tesla has very loud warnings as soon as the first firewall breaks between cells which according to multiple incidents happens at least 5-10 minutes before enough cells hit critical temperatures that the entire vehicle becomes fire. Far more warning than an ICE fire.

There's probably a case to make that there should be an effort to provide better, similar software warnings for parked/"off" vehicles to signal emergency services with that extra lead time.


> Tesla has very loud warnings as soon as the first firewall breaks between cells

I searched but wasn't able to find a video of this. Any reference?


The “explosions” you hear from car fires are almost always first the tires popping, and later the airbags going off. I watched a car fire near me last year and the firefighters didn’t even flinch when the loud bangs happened.


Lithium batteries are far more explodey than modern gas tanks. Battery fires burn much hotter and faster than "regular" vehicle fires (which are generally just the contents of the vehicle burning, not the fuel).


> It seems to me that being harder to put off but occurring less frequently, and most importantly not exploding (leaving significant amount of time for occupants to get out, if they are able) is a pretty good trade off.

It's very rare to get a gas tank to explode (as others have pointed out). You need to have very little fuel (or better, none at all) in the tank before a spark will cause explosions.

Take a 2l plastic soda bottle, fill it 90% full with petrol and (with tongs from a distance) drop in a lit cigarette. I've tried to get the bottle to go bang multiple times and it never happens - the ciggarette is extinguished every single time.

Then empty that bottle until there is less than 5ml of petrol in it, close the bottle and shake it up to get a rich mixture, and then repeat the experiment (I've gotten fairly big bangs every single time, this way).

The TLDR of it all is that there is danger of explosion when the tank is emptied, not when it is full, because the fumes cause explosions, not the liquid state of the fuel (which just catches fire).


Yes, as I understand it, the fuel vapors give a relatively minor boom that disperses the rest of the gasoline enough to become essentially the second stage. Not that it takes long enough to really discern two stages: aerosolized gasoline will go up fast.


How long would you suggest those tongs should be, to ensure a safe distance? For the ones that go bang.


> How long would you suggest those tongs should be, to ensure a safe distance? For the ones that go bang.

I'm hesitant to answer in case some tries this and gets hurt.

I used a flexible claw (one like this: https://www.amazon.com/Flexible-Claw-Automotive-Mechanic-Gen...) inserted into a standard copper pipe (used for taps and other plumbing) to stiffen the spring and held it at arms length.

So, about 2m was safe for me. I also suggest wearing protection for your ears as these are really loud bangs, and protection for your eyes as well (it is an explosion, after all).


I think, given the HN community, the appropriate answer is "build a robot to do it for you"




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