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> The big takeaway from these fires is that proper safety for EVs might soon mean not leaving them in garages Just add a fire suppressant system to the Powerwa

> The big takeaway from these fires is that proper safety for EVs might soon mean not leaving them in garages Just add a fire suppressant system to the Powerwall it's hooked on.

tonyhb 5y ago
Not sure it's as easy as adding a fire suppressant system to a garage. In many tesla crash reports firefighters leave the batteries to burn for hours, as there's no nice way to extinguish lithium fires.
- aequitas 5y ago
  Standard procedure nowadays seems to be to dump the car in a container filled with water: https://www.autoevolution.com/news/bmw-i8-catches-fire-in-the-netherlands-firefighters-drop-it-in-water-container-133267.html https://www.autoevolution.com/news/bmw-i8-catches-fire-in-th...
  - tonyhb 5y ago
    This is absolutely insane and all I can think of is a total wipeout style dunk tank under our garages in case of fires.
TimSchumann 5y ago
Uh, someone correct me if I'm wrong on this... but aren't most Lithium Ion battery chemistries self oxidizing? If that's the case, I don't think a fire suppression system would help.
- kayodelycaon 5y ago
  You're correct. They are. That's why you can't put them out unless you drop the whole thing in a giant container of water.
- i_am_proteus 5y ago
  It's possible to put the fire out by cooling the battery below ignition temperature, and depriving the fire of atmospheric oxygen certainly reduces the combustion rate, but the result for firefighters is that an enormous amount of water is required. Typical petroleum fires (gasoline, diesel) can be smothered with foam to put them out. No amount of heat will ignite these fuels without oxygen. Smother a self-oxidizing fire does not extinguish the fire. To remove heat, firefighters spray cold water on the fire, which is incompatible with smothering it (the water and steam push foam away), so the fire has atmospheric oxygen as well as oxidant from the fuel. Dropping the car into a tank of water accomplishes both - the water tank is a heat sink, cooling the car, and it also smothers the fire and removes atmospheric oxygen.
- lb1lf 5y ago
  -I recall having read of at least two incidents where Norwegian firefighters simply dumped a truckload of sand over the burning vehicle. This happened in places where simply leaving it to burn out wasn't an option. Crude, but effective, apparently. Massive heatsink+depriving the fire of any oxygen not supplied by the decomposing battery.

> The big takeaway from these fires is that proper safety for EVs might soon mean not leaving them in garages Just add a fire suppressant system to the Powerwall it's hooked on.

tonyhb 5y ago

Not sure it's as easy as adding a fire suppressant system to a garage. In many tesla crash reports firefighters leave the batteries to burn for hours, as there's no nice way to extinguish lithium fires.

aequitas 5y ago
Standard procedure nowadays seems to be to dump the car in a container filled with water: https://www.autoevolution.com/news/bmw-i8-catches-fire-in-the-netherlands-firefighters-drop-it-in-water-container-133267.html https://www.autoevolution.com/news/bmw-i8-catches-fire-in-th...
- tonyhb 5y ago
  This is absolutely insane and all I can think of is a total wipeout style dunk tank under our garages in case of fires.

TimSchumann 5y ago

Uh, someone correct me if I'm wrong on this... but aren't most Lithium Ion battery chemistries self oxidizing? If that's the case, I don't think a fire suppression system would help.

kayodelycaon 5y ago
You're correct. They are. That's why you can't put them out unless you drop the whole thing in a giant container of water.
i_am_proteus 5y ago
It's possible to put the fire out by cooling the battery below ignition temperature, and depriving the fire of atmospheric oxygen certainly reduces the combustion rate, but the result for firefighters is that an enormous amount of water is required. Typical petroleum fires (gasoline, diesel) can be smothered with foam to put them out. No amount of heat will ignite these fuels without oxygen. Smother a self-oxidizing fire does not extinguish the fire. To remove heat, firefighters spray cold water on the fire, which is incompatible with smothering it (the water and steam push foam away), so the fire has atmospheric oxygen as well as oxidant from the fuel. Dropping the car into a tank of water accomplishes both - the water tank is a heat sink, cooling the car, and it also smothers the fire and removes atmospheric oxygen.
lb1lf 5y ago
-I recall having read of at least two incidents where Norwegian firefighters simply dumped a truckload of sand over the burning vehicle. This happened in places where simply leaving it to burn out wasn't an option. Crude, but effective, apparently. Massive heatsink+depriving the fire of any oxygen not supplied by the decomposing battery.