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Massive EV cement truck fire: official 'explanation' versus the facts.

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thm_w:

--- Quote from: EPAIII on December 21, 2023, 03:18:34 am ---That statistic may be true, but it sounds like it needs to be clarified.

One thing I would ask about is just how big the fire events were. Perhaps I am wrong, but when a gas or diesel vehicle catches fire, it can be easily extinguished. I had a fire in my gas powered truck on a highway trip and was able to put it out with the small fire extinguisher that I carried. I even had time to pull over to the shoulder of the road, get out of the truck, open the hood, observe the fire, go into the trailer to get the extinguisher, return to the truck, and put the fire out. I did this myself, with a small extinguisher. And after it cooled down, I was able to drive the truck and trailer to the next exit where repairs were made.
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You are giving an example which wouldn't even have been in the gas vehicle fire statistics, not the greatest example but OK.
Your concerns should be resolved by having the appropriate tools for the fire department, sprinklers or other systems inside car parks to mitigate fire spread where possible. As mentioned above, as LFP gets wider adoption, spread will be less of an issue if at all.


--- Quote ---In work by Willstrand et al., heat release rates (HRR) from full-scale fire tests performed in recent years with modern vehicles, including both ICEVs and BEVs was summarised. The compiled data showed a minor difference in the total energy released during the fire (total heat release) between ICEVs and BEVs. The total heat release for ICEVs range between 3.3 to 10 GJ and for BEV between 4.7 to 8.5 GJ. No difference in peak heat release rate or effective heat of combustion could be seen for the compared vehicles (Willstrand et al., 2020).
--- End quote ---

https://lashfire.eu/media/2022/09/2022-08_Facts_and_Myths.pdf



--- Quote from: coppercone2 on December 21, 2023, 08:18:34 pm ---people need to try driving EV, their just better. gasoline is horse and buggy and feels like it! stretchy cars. I feel like its those people warning me against the first Lion power drills (mid 2000's makita), which ended up utterly kicking ass. In the early 2000's there was down right prosecution against my makita drill acquisiton.

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Yeah but how many horse and buggy fires are there? Clearly the safest and more superior mode of transportation.

EEVblog:

--- Quote from: Marco on December 21, 2023, 07:42:07 am ---Once all fire departments get injection spikes, extuingishing EV fires should be easy enough. Sprinklers will keep it under control regardless.

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What are "injection spikes"?

thm_w:

--- Quote from: EEVblog on December 22, 2023, 01:58:55 am ---
--- Quote from: Marco on December 21, 2023, 07:42:07 am ---Once all fire departments get injection spikes, extuingishing EV fires should be easy enough. Sprinklers will keep it under control regardless.

--- End quote ---

What are "injection spikes"?

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Sounds like this thing: https://ctif.org/news/new-revolutionary-method-extinguishes-lithium-ion-ev-fires-ten-minutes-minimal-water
"Cobra Ultra High Pressure Lance (UHPL) firefighting equipment – this equipment uses abrasive entrained in water to pierce and then water mist to suppress/extinguish. This is all applied using one continuous action. This uses water at 58 l/min."

There are also tools which are just blocks to direct the angle from under the car up toward the battery: https://arstechnica.com/cars/2021/11/new-firefighting-tool-delivers-water-directly-to-blazing-ev-batteries/ as a normal hose doesn't work that well.

EPAIII:
Water cooling to the cells. Interesting thought and it seems like a good idea.

But water boils and the steam escapes.

So the question then becomes, just how much water can a vehicle carry for battery emergencies? Even a large vehicle like a dump truck or a tractor for a semi? How much WOULD they carry when it will cost them dollars or euros or whatever currency for the extra battery charging for every kilo of water carried.

I would bet that it would not be long before that water tank is at the lowest possible level 100% of the time.

And a battery emergency occurs and the extra water starts flowing to that cell to keep it cool. A red light comes on in the cab. What does the driver do then? Stop on the side of the highway and call for help? Try to get to the next exit and hope there's facilities there? Just keep on trucking because he needs to be on schedule? Or what?




--- Quote from: Marco on December 21, 2023, 07:42:07 am ---
--- Quote from: EPAIII on December 21, 2023, 03:18:34 am ---Perhaps I am wrong, but when a gas or diesel vehicle catches fire, it can be easily extinguished.
--- End quote ---
Just google for gas tank rupture fire.

Once all fire departments get injection spikes, extuingishing EV fires should be easy enough. Sprinklers will keep it under control regardless.

I wonder though if with good design with water cooled batteries it would really be impossible to keep a shorting cell below ignition temperature. Maybe have a compartmentalized design and increase flow to a compartment if something goes wrong? Hell, that might already be best practice for all I know.

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EPAIII:
Airport car park! Been there. They are one of the loneliest places in any city. I wonder just how many cars were either on fire or completely burned out BEFORE ANYONE even noticed there was a fire.

If I was setting the odds on a Las Vegas bet on that, I would set the percentage of already lost vehicles at about 50% for the 50/50 break point in the odds. In other words, I think it is an even bet that a full HALF of the cars there were destroyed before the alarm went in. And THEN the fire department had to actually get there, possibly in time to watch helplessly while the last 5% or 10% of the vehicles went up in flames.

I am not a doom's day guy. I really am not. I have watched that "doom's day clock" on the Bulletin of the Atomic Scientists for over 50 years now and never really worried about nuclear war.

https://thebulletin.org/doomsday-clock/current-time/

But this really, really has me concerned. And I fear that is far more likely than nuclear war breaking out. It is almost inevitable if nothing is done.

If a battery fire can destroy 1500 vehicles in an airport car park, think what it could do in the lower floors of a tall office building. One of the 9-11 aircraft was said to carry 20,000 gallons of jet fuel, which was the actual weapon used by the terrorists to bring those building down. With 90% of 1500 autos, each having a partial tank of gasoline you could easily have that same 20,000 gallons of fuel. And access to such an office building's parking area would be far, far more difficult for the fire department. I don't think you can glibly say that when all the fire departments get the correct tool, the problem is solved. They must get to that FIRST EV in time to actually use that device before the fire spreads out of control.

I just don't want to pick up the paper one morning or turn on the TV news and see another building that has collapsed into a heap of ashes. I just don't want to see that!




--- Quote from: MT on December 21, 2023, 12:43:45 pm ---
--- Quote from: EEVblog on December 21, 2023, 02:33:04 am ---More than 200 truck fires in NSW alone every year:
https://www.epa.nsw.gov.au/newsletters/epa-connect-newsletter/september-2022/guide-to-help-prevent-truck-fires

--- End quote ---

Not even close to the Luton car park fire, 1500 cars burned in one go, caused by one battery hybrid car! :)


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