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Extinguishing the EV Battery Fire Hype

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Re: Extinguishing the EV Battery Fire Hype

#41

Post by thebruce87m »

NooneAtAll3 wrote: post #4

When statistics are presented on fires per car sold, does it account for car age? I'd assume that average ICE car catching on fire is older that average EV just by EV not existing when ICE was made

https://thedriven.io/2023/05/16/petrol-and-diesel-cars-20-ti...

> Furthermore, fires in electric cars are declining. The MSB says the number of fires in electric cars has been around 20 a year over the last three years

The number of fires should increase if age was a linear factor. Could be non linear of course.

Re: Extinguishing the EV Battery Fire Hype

#42

Post by rootusrootus »

zelon88 wrote: post #28

How can you have an article about battery combustion without talking about the chemistry? A gasoline fire is a well understood event. Gas ignites and burns until there is no more fuel, or no more air. We know to extinguish this type of fire, we need to remove the air. Once the reaction has stopped, it would need another fresh ignition source to reignite. A lithium fire is, on the other hand, is almost completely misu…

Aren't most fires, especially big ones, extinguished by cooling them down?

Re: Extinguishing the EV Battery Fire Hype

#43

Post by thebruce87m »

bob1029 wrote: post #8

You'll never catch me with a lithium ion battery larger than ~150wH inside my home. I don't care how aggressively the statistics are massaged. I've personally experienced laptop and cellphone batteries catching on fire and can see how something with 100x+ the capacity could cause some serious fucking trouble. Anyone who has one of those 1kWh+ emergency power backup things sitting inside their house right now really n…

Spontaneous ICE car fires are most likely to be caused by the 12V systems, so you’re not going to smell gasoline.

Here’s an example:

> Tension on the transmission wiring harness could lead to wire insulation pulling back from the electrical connector. As a result, water from external sources could penetrate the connector. The presence of water may create a short circuit over time. As a result, the short circuit could lead to thermal overload if the vehicle's ignition is off for longer periods of time. Subsequently, the risk of fire cannot be ruled out.

https://static.nhtsa.gov/odi/rcl/2022/RCLRPT-22V533-6872.PDF

Re: Extinguishing the EV Battery Fire Hype

#44

Post by Tagbert »

verisimi wrote: post #38
_ea1k wrote: post #10

Earlier quoted context omitted.

Sure, but that seems like mostly a question of getting them to a place where that can safely happen. Once it is isolated, let it burn out if it reignites. Putting it out the first time so that it can be safely moved is important.

> Once it is isolated, let it burn out if it reignites. Mere words do not quite convey the issue. How does one "isolate" a car? Does one take it somewhere? Where? Are fire engines able to undertake this task? It's there a concern en route to the somewhere?

The same tow trucks that would tow away vehicles after a crash would tow an EV to an impoundment yard where it could be monitored.

Re: Extinguishing the EV Battery Fire Hype

#45

Post by thebruce87m »

zdragnar wrote: post #23
DannyBee wrote: post #20

Earlier quoted context omitted.

ICE fires occur in stationary as well. It's just that we have learned to handle gas better over the years. I otherwise agree, but it's complicated because while what you say in the first sentence is true, it was true for ICE at one point too. So for example, this is why gas containers have pressure releases, etc. I mean, for an ICE vehicle you go to a gas station and fill it up. It's hard these days to think about ho…

This is a lot of words to say that EVs are currently more dangerous than ICE vehicles to park in a garage.

There are no statistics to back up this statement. All we know is that both EVs and ICE car’s spontaneously combust on rare occasions. There are examples of both here: https://normantaylor.com/blog/which-cars-catch-fire-the-most...

What’s interesting to me is that most people talk about NMC batteries in EVs, but from what I can tell LFP batteries should be safer and are becoming more popular. Would be good to see if there are stats to back this up.

Re: Extinguishing the EV Battery Fire Hype

#46

Post by squarefoot »

dataflow wrote: post #18
vel0city wrote: post #7

Earlier quoted context omitted.

ICE fires aren't often related to collisions. I've seen a neighbor's house burn down due to a car that had been parked in their garage for hours combusting. I've had multiple ICE cars recalled for catching fire when stopped. In the examples in the articles they mentioned vehicles in parking garages and on cargo ships, those weren't moving. Your general impressions don't reflect reality. Out of all the cars I've owned…

> I've seen a neighbor's house burn down due to a car that had been parked in their garage for hours combusting The ICE car combusted while the engine wasn't running? Like, it was parked, they'd turned off the car as usual, and hours later it randomly combusted? Do you have any information on what the likely cause may have been? (e.g., hot weather? unexpected sparks?)

> Do you have any information on what the likely cause may have been? (e.g., hot weather? unexpected sparks?)

Possibly one of the above plus gasoline vapors which are a lot more dangerous and explosive than gasoline itself and can be easily ignited by a spark not necessarily due to a short circuit.

Re: Extinguishing the EV Battery Fire Hype

#47

Post by [deleted] »

Qwertious wrote: post #39
api wrote: post #34

Earlier quoted context omitted.

Gas cars spontaneously igniting are rare, but flammable liquids like solvents or gasoline for lawn equipment catching fire and causing massive destruction is fairly common. People often do things like store solvents in basements where fumes can get loose and get near furnaces and other equipment and ignite. Stored energy is stored energy. You do have a bit of a point about large lithium power bricks. I trust those th…

>Stored energy is stored energy. There's plenty of stored energy in a slab of solid steel, but that doesn't make it remotely dangerous. What makes lithium-batteries dangerous is the thermal runaway , enabled by the liquid capacitor.

[deleted]

Re: Extinguishing the EV Battery Fire Hype

#48

Post by api »

Qwertious wrote: post #39
api wrote: post #34

Earlier quoted context omitted.

Gas cars spontaneously igniting are rare, but flammable liquids like solvents or gasoline for lawn equipment catching fire and causing massive destruction is fairly common. People often do things like store solvents in basements where fumes can get loose and get near furnaces and other equipment and ignite. Stored energy is stored energy. You do have a bit of a point about large lithium power bricks. I trust those th…

>Stored energy is stored energy. There's plenty of stored energy in a slab of solid steel, but that doesn't make it remotely dangerous. What makes lithium-batteries dangerous is the thermal runaway , enabled by the liquid capacitor.

We got pretty good at making it acceptably safe to drive around at 80mph with tanks of volatile liquid fuel right behind or under us. We’ll get good at this too. Lithium batteries are already surprisingly safe for what they are.

Re: Extinguishing the EV Battery Fire Hype

#49

Post by vel0city »

marcosdumay wrote: post #40
vel0city wrote: post #7

Earlier quoted context omitted.

ICE fires aren't often related to collisions. I've seen a neighbor's house burn down due to a car that had been parked in their garage for hours combusting. I've had multiple ICE cars recalled for catching fire when stopped. In the examples in the articles they mentioned vehicles in parking garages and on cargo ships, those weren't moving. Your general impressions don't reflect reality. Out of all the cars I've owned…

To be fair, ICEs tend to cath fire while they are moving. That's the time every system in the car is most stressed. That means the odds of it catching fire on your garage while you sleep are lower. EVs by their turn are highly stressed while charging.

> ICEs tend to cath fire while they are moving.

This is not backed by any evidence while the opposite is shown in the referenced paper. Most ICE fires happen when parked according to actual data.

Re: Extinguishing the EV Battery Fire Hype

#50

Post by ben-schaaf »

zelon88 wrote: post #28

How can you have an article about battery combustion without talking about the chemistry? A gasoline fire is a well understood event. Gas ignites and burns until there is no more fuel, or no more air. We know to extinguish this type of fire, we need to remove the air. Once the reaction has stopped, it would need another fresh ignition source to reignite. A lithium fire is, on the other hand, is almost completely misu…

A lithium-ion battery fire is not a lithium fire; the lithium hexafluorophosphate electrolyte is non-flammable. You're mostly right about the rest, but it's really important to note that it's not a lithium fire.

Lithium combusts in the presence of water, so fighting a lithium(not-ion) battery fire requires special care.

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