Quote Originally Posted by Mirek View Post
You try to downplay a very real concern. What happens with a petrol car burning is just the fire. If you have a fire truck you extinguish it rather easily (of course it's a problem in the middle of the forest with a hand extinguisher). Even if you extinguish by water nothing serious happens. You can do that.

But if lithium-ion batteries start to burn just next to the fire truck it will probably won't make much difference to them burning in a remote place in the forest. Moreover if you try to extinguish it with water you will only add to the explosive power by adding hydrogen to the fire. If this happens somewhere in the forest it's much worse than with the petrol car because you can't effectively stop the fire from spreading until you cover all of that and the surroundings with a thick foam. For that you need very serious hardware. Something like airport fire trucks.

What is worst about that is that lithium-ion batteries like to start burning long time after they are damaged. This is what can never happen with petrol car. It can't simply start to burn in parc ferme in the middle of the night. The electric car can.
You try to upplay a concern.

As you said yourself and as proved by all the recent rally car fires, they can't stop the fire for petrol cars either, unless they stop next to a fire truck like Veiby in Portugal. So what happens is that the car burns until there is nothing to burn and all that is done is keep the fire from spreading. Which is the same that would be done with battery fire.

Yes the battery fire will burn longer and with higher temperature. But if you know you have batteries that can take fire you use fire-extinguishers applicable for that (foam, CO2, various versions with particles) that keep it from becoming too intense. For spreading in forest water on surroundings will work just fine.

Batteries catch fire if they are damaged or if they overheat. In high performance electric car battery temperature management is one of the most important systems so yes that has to be designed properly. For damage you off course have to focus on protecting the battery. Which again has to be focused on but in a car with rollcage and lot of empty space (no engine/exhaust etc, no rearseats++) it should be possible. Civilian battery cars don't burn everywhere around in crashes, quite the opposite. Yes they don't "race", but again they don't have rollcages++ either.

And here we are again to the fire actually starting (if it does) it's not like it's nuclear fuel burning, keep it from spreading at let it burn.. just like you do with petrol rally car.

Btw. the argument about fire starting later is also funny, cause that's exactly what happened to Breen in Turkey.