How to put out an EV fire...
Discussion
I know the subject is electric scooters, but there's some really interesting stuff in this near the middle about the difficulties of knowing when car has stopped burning (submerging them in water for weeks?!?!). And also a lot on battery fire risk in general.
Well worth a watch: https://www.youtube.com/watch?v=TPVVtTACQhE
Well worth a watch: https://www.youtube.com/watch?v=TPVVtTACQhE
like everything , you get what you pay for. when buying anything running off a string of 18650 batteries (presumably), it's a good idea to check what cells make up the pack. i wouldn't but a car with fuel tank made of just enough layers of aluminium foil to hold 80 litres of fuel.
however, when buying an electric scooter/ skateboard etc, i can guarantee one of the most common filters applied to the search is 'price low - high'
however, when buying an electric scooter/ skateboard etc, i can guarantee one of the most common filters applied to the search is 'price low - high'
tamore said:
like everything , you get what you pay for. when buying anything running off a string of 18650 batteries (presumably), it's a good idea to check what cells make up the pack. i wouldn't but a car with fuel tank made of just enough layers of aluminium foil to hold 80 litres of fuel.
however, when buying an electric scooter/ skateboard etc, i can guarantee one of the most common filters applied to the search is 'price low - high'
True but the different way an EV burns to an ICE can't be dismissed. This isn't purely down to an ev self combusting but just being involved in a fire. however, when buying an electric scooter/ skateboard etc, i can guarantee one of the most common filters applied to the search is 'price low - high'
For example, what happens when insurance underwriters stop covering car ferries because of the elevated risk due to the different type of fire? How do you insure the Chunnel of the trains and even the tunnel itself have not been engineered to withstand the different nature of such a fire? Underground car parks where the concrete and steel pillars which hold up the offices above also have not been designed to withstand that type of heat event so to maintain insurance cover the landlord may have to close the car park or close it to EVs?
Once we have twenty year old EVs with shagged battery packs being parked in residential garages which haven't been built to withstand the heat from such a fire, you're not going to be able to insure your home.
Statistically, I suspect the number of times an EV will burst into flames is lower than an ICE. But the actual problem is that when it does happen not much of the planet that has been built for ICEs has been built to tollerate issues with EVs.
DonkeyApple said:
True but the different way an EV burns to an ICE can't be dismissed. This isn't purely down to an ev self combusting but just being involved in a fire.
For example, what happens when insurance underwriters stop covering car ferries because of the elevated risk due to the different type of fire? How do you insure the Chunnel of the trains and even the tunnel itself have not been engineered to withstand the different nature of such a fire? Underground car parks where the concrete and steel pillars which hold up the offices above also have not been designed to withstand that type of heat event so to maintain insurance cover the landlord may have to close the car park or close it to EVs?
Once we have twenty year old EVs with shagged battery packs being parked in residential garages which haven't been built to withstand the heat from such a fire, you're not going to be able to insure your home.
Statistically, I suspect the number of times an EV will burst into flames is lower than an ICE. But the actual problem is that when it does happen not much of the planet that has been built for ICEs has been built to tollerate issues with EVs.
Don’t EV batteries hold much less energy than a tank of petrol? And electricity doesn’t form a big burning river like petrol does.For example, what happens when insurance underwriters stop covering car ferries because of the elevated risk due to the different type of fire? How do you insure the Chunnel of the trains and even the tunnel itself have not been engineered to withstand the different nature of such a fire? Underground car parks where the concrete and steel pillars which hold up the offices above also have not been designed to withstand that type of heat event so to maintain insurance cover the landlord may have to close the car park or close it to EVs?
Once we have twenty year old EVs with shagged battery packs being parked in residential garages which haven't been built to withstand the heat from such a fire, you're not going to be able to insure your home.
Statistically, I suspect the number of times an EV will burst into flames is lower than an ICE. But the actual problem is that when it does happen not much of the planet that has been built for ICEs has been built to tollerate issues with EVs.
buggalugs said:
Don’t EV batteries hold much less energy than a tank of petrol? And electricity doesn’t form a big burning river like petrol does.
Basically true. The car might keep on catching fire, which I'm sure a fire fighter would describe as 'irritating' to say the least. But so long as those in the car exit it swiftly, in fuel terms there is less to burn and it will remain a localised fire. Also no chance of one huge and unpredictable fireball, albeit that's surprisingly rare for ICE cars anyway.When we eventually have solid state batteries, no fire risk whatsoever - at least not from the cells. I guess other mechanicals could still somehow catch fire.
Ten years later of EV's driving around the planet and despite the media's best efforts to cover burning EV's, the truth is there have been less % wise than ICE and overall they are generally considered safer by the various studies carried out.
Large fire blankets appear to be a popular option with Fire Services/Departments
e.g. https://fireisolator.com/#what-is-fire-isolator
e.g. https://fireisolator.com/#what-is-fire-isolator
Putting out the fire doesn't seem to be the problem though. It's more the fact that hours after giving the all clear, a fire on the opposite side of the cell pack starts up. Putting the first fire out doesn't count for anything if a new fire has the potential to start.
This is definitely an over-exaggerated problem as it's very rare and overall ICE fires remain more common. But I can completely understand the frustration amongst the emergency service teams that give the press quotes.. These guys just want to declare the situation safe and move on to the next emergency - not return several times to start from scratch again. Especially not if joe blogs public is watching on judging you for not being able to put it out properly the first time.
I'm a big fan of EV but all new technologies have their issues. Li-ion cell tech has this issue. It's absolutely going to p
s off the emergency services when it happens.
This is definitely an over-exaggerated problem as it's very rare and overall ICE fires remain more common. But I can completely understand the frustration amongst the emergency service teams that give the press quotes.. These guys just want to declare the situation safe and move on to the next emergency - not return several times to start from scratch again. Especially not if joe blogs public is watching on judging you for not being able to put it out properly the first time.
I'm a big fan of EV but all new technologies have their issues. Li-ion cell tech has this issue. It's absolutely going to p
s off the emergency services when it happens.buggalugs said:
Don’t EV batteries hold much less energy than a tank of petrol? And electricity doesn’t form a big burning river like petrol does.
That's not specifically the issue. Certain structures have been built to withstand a certain type of fire for a certain length of time. Fire systems are obviously designed for a specific task and ultimately can be upgraded but it's a bit more difficult with physical structures. We already have syndicates pulling out of certain covers. Not a problem at the moment as there's no shortage of others happy to take premium but you're only one event away from being in the Gobi.
DonkeyApple said:
buggalugs said:
Don’t EV batteries hold much less energy than a tank of petrol? And electricity doesn’t form a big burning river like petrol does.
That's not specifically the issue. Certain structures have been built to withstand a certain type of fire for a certain length of time. Fire systems are obviously designed for a specific task and ultimately can be upgraded but it's a bit more difficult with physical structures. We already have syndicates pulling out of certain covers. Not a problem at the moment as there's no shortage of others happy to take premium but you're only one event away from being in the Gobi.
Shooting from the hip, I would guess that most ICE fires happen on the open road when something overheats or there's an accident. From posts on here and elsewhere, EV fires seem to occur mostly during charging so are perhaps more likely to be in a residential setting.
4Q said:
You can get lithium battery specific fire extinguishers. We have some at work.
Seen these, but I believe they are only useful in the scenario of a small scale battery, and allowing you to get close enough to move (carefully) to somewhere safer.They just temporarily stop the external flames, and do nothing to stop the internal thermal runaway.
Mikehig said:
I've read that some towns in Germany (iirc) have banned EVs from car parks under buildings.
Shooting from the hip, I would guess that most ICE fires happen on the open road when something overheats or there's an accident. From posts on here and elsewhere, EV fires seem to occur mostly during charging so are perhaps more likely to be in a residential setting.
I hadn't read of any bans as of yet but it's a big looming issue. What gets omitted is that it doesn't have to be the EV that starts the fire but as they become more prevalent then they will get caught up in other fires and the fact that they burn very differently needs to be accounted for in not just suppression systems but actual architecture. Shooting from the hip, I would guess that most ICE fires happen on the open road when something overheats or there's an accident. From posts on here and elsewhere, EV fires seem to occur mostly during charging so are perhaps more likely to be in a residential setting.
In very simple terms, with a domestic integral garage the building regs stipulate certain criteria/materials to slow the penetration of a fire that is emanating from that garage but those regs are defined by data that is solely from ICE cars. The data from an EV being caught up in a domestic fire is going to be manifestly different and that almost certainly means the regs will need to adapt.
Basement spaces such as underground car parks are another big issue. The risk is being recognised within the backup power market where landlords are seeking to install battery storage in these areas and the industry is building these batteries within fire boxes that are designed to firstly allow suppression systems to work but also to temper any impact on structural elements of the building but when that evolves to take cars into consideration the cost of meeting an insurers requirements may be such that the car park closes either completely or to EVs.
It's a reality that can't be catered for just by EVs being statistically safer at this moment in time but has to consider the ramifications of an EV being involved in an incident not started by that EV as well as the eventual appearance of large numbers of old EVs. With the latter, we would at least hope to see data from China well before it's any kind of issue here as they have been building EVs for longer, they're more common and they will certainly have been building plenty with cheap and mismatched power cells while also their rampant and under regulated building industry will be containing no shortage of issues that will start to appear over the next thirty years.
Evanivitch said:
4Q said:
You can get lithium battery specific fire extinguishers. We have some at work.
Seen these, but I believe they are only useful in the scenario of a small scale battery, and allowing you to get close enough to move (carefully) to somewhere safer.They just temporarily stop the external flames, and do nothing to stop the internal thermal runaway.
4Q said:
The manufacturers (and the fire brigade inspector who visited 2 weeks ago) say different.
It's really great that AVD are selling a product to the (unwitting) commercial sector before they've managed to sell to the huge aerospace and defence sectors that have been looking for a viable lithium battery fire solution for the last decade.Err, yeah...
AVD's own website suggests it creates an oxygen barrier. Lithium batteries in thermal runaway don't need atmospheric oxygen. AVD also claim it cools the reaction. Err yeah, you're not going to cool much with a couple litres of water at room temperature.
I’ve seen this brought up before and I think it’s a bit alarmist.
The key metrics are the heat release rate (HRR) and heat flux (HF) (intensity) produced during such an event. That is what buildings etc are designed for. Does an EV fire have higher HRR and HF than an ICE fire? There’s no difference in the car itself. They will burn the same as they’re, well, the same. The primary difference is a large battery vs 60-100L of fuel burning. Liquid fuel burning has a FAR higher HRR and HF than a burning battery does. So is more hazardous to any surrounding structures, simply because it’s putting more heat energy more quickly, more intensely into it. A battery is harder to fully extinguish, but as it won’t be burning anywhere near as intensely, its easier to manage and contain the fire vs a raging out of control fuel fire.
The key metrics are the heat release rate (HRR) and heat flux (HF) (intensity) produced during such an event. That is what buildings etc are designed for. Does an EV fire have higher HRR and HF than an ICE fire? There’s no difference in the car itself. They will burn the same as they’re, well, the same. The primary difference is a large battery vs 60-100L of fuel burning. Liquid fuel burning has a FAR higher HRR and HF than a burning battery does. So is more hazardous to any surrounding structures, simply because it’s putting more heat energy more quickly, more intensely into it. A battery is harder to fully extinguish, but as it won’t be burning anywhere near as intensely, its easier to manage and contain the fire vs a raging out of control fuel fire.
Not Germany, but this popped up today in Belgium (Dutch article).
https://www.vrt.be/vrtnws/nl/2022/02/14/brandweer-...
The fire chief in Brussels is indeed not complaining about the frequency but is asking for some policies as the fires can take days (not weeks) so the car needs to be towed out (often while burning/temporary not burning).
Some requests are sensible, others aren't really feasible (like restricting areas where EV's can park):
This is interesting though:
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Research by another firm, AutoinsuranceEZ, says battery electric vehicles have just a .03% chance of igniting, compared to internal combustion engine vehicle’s 1.5% chance. Hybrid electrics, which have both a high voltage battery and an internal combustion engine, have a 3.4% likelihood of vehicle fires according to their study.
---
If you ever need another reason not to get a hybrid
https://www.vrt.be/vrtnws/nl/2022/02/14/brandweer-...
The fire chief in Brussels is indeed not complaining about the frequency but is asking for some policies as the fires can take days (not weeks) so the car needs to be towed out (often while burning/temporary not burning).
Some requests are sensible, others aren't really feasible (like restricting areas where EV's can park):
- Better ventilation in case of fire for the toxic fumes
- Forbid fast chargers under ground
- Park no lower than -1 and always close to an exit
This is interesting though:
---
Research by another firm, AutoinsuranceEZ, says battery electric vehicles have just a .03% chance of igniting, compared to internal combustion engine vehicle’s 1.5% chance. Hybrid electrics, which have both a high voltage battery and an internal combustion engine, have a 3.4% likelihood of vehicle fires according to their study.
---
If you ever need another reason not to get a hybrid
Edited by ZesPak on Monday 14th February 16:31
I'll try and find the article, might be Jalopnik, about EV fires - suggested that they arent as common as you might think and that Hybrids are the ones that are the worst by far! In fact BEV's were the least likely to end up with a fire. The problem is that once they get going, you really arent going to put them out, but then again.
off_again said:
I'll try and find the article, might be Jalopnik, about EV fires - suggested that they arent as common as you might think and that Hybrids are the ones that are the worst by far! In fact BEV's were the least likely to end up with a fire. The problem is that once they get going, you really arent going to put them out, but then again.
I believe that it is statistically correct that EV fires aren't as common place as ICE. That may be true but one does have to consider that you are contrasting a small dataset relating to new vehicles with a a much larger data set that comprises of old clunkers with rotten fuel lines etc. But the more important observation is that you cannot just look at isolated combustion but fires in general where a car would get caught up. Ie, we know people don't often spontaneously combustion but we do know that they burn in house fires.
I work in automotive logistics and we have at our HQ site an shipping container that's got sand or similar in it out the back of the warehouse, we store EV battery packs in the warehouse awaiting call off (also E scooters), there is a temp sensor 24/7 in the area where the batteries are and a documented procedure to get them out of the warehouse into the container if the temp increases.
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