Fires in EVs

What causes a lithium battery to catch fire?

Battery packs consist of thousands of cells packed together. During a thermal runaway, the heat generated by a failed cell can move to the next cell, causing it to become thermally unstable as well. This chain reaction can cause the entire pack to be destroyed within a few short seconds.

Nice blog that covers this topic ...

https://www.ionenergy.co/resources/blogs/battery-safety/

I'm thinking a tank of gasoline is much safer...

Safety of course is a matter of perspective depending on how one defines safety, but I guess the only thing I can offer is that a tank of gasoline is better understood.

What an excellent topic for a Google search.

Helpful!

People focus on EV fires, making it appear common, but how many gasoline car fires and explosions happen every day? The answer is that we rarely hear because it rarely gets reported (beyond the traffic reports when it causes a problem). A recent US govt report concluded that gasoline fires in cars are roughly 100x more common than EV fires, but that doesn’t make the news.

https://www.autoinsuranceez.com/gas-vs-electric-car-fires/

I'm pretty sure that my car, with the battery shut off, is not going to burst into flames while parked in the garage and burn the house down while my family is sleeping....Electric car? not so much....

There have been a number of recalls for ICE-powered vehicles in the last couple of decades in which the recall notice warned the owner not to park the recalled vehicle in a garage attached to a house because there was a significant risk of the defective part starting a fire even when the car was shut down.

That's why you have a battery disconnect...no chance of short to start a fire...not really possible in an EV which is probably on the charger all the time it's parked...

Don't really care about the car as much as I do my family....the vehicle catching fire in traffic or along the road should not hurt anybody, and insurance should cover the damage....It's the starting on fire while parked, that's a concern for me...It's a sneak attack that can't be anticipated...

Hey now, what's a tiny bit of local warming if you are spared the global one? You can't have it all now, can you?

Now that unprovoked local meltdown ehm.. warming seems to be happening only on individual compromised cells. The rest, that just follow a chain reaction are completely innocent and we shouldn't be pointing fingers.

Compromising cells now is done -unless from a manufacturing flaw which is rare- only if you ask a cell to go over its individual margin of safety one time more than you should. Too fast charging or discharging for the conditions or a charger-inverter circuit glitch, mechanical damage from shocking or vibration and shell deformation etc. Now where can this happen in a car is beyond me.

Now to get a bit serious, a cell by cell 24/7 parameter and health monitoring can be implemented and the posibility to isolate any single suspect cell get integrated in the system, plus a bit of local cooling and/or fire extinguishing if something gets out of hand is feasible technically. I also can't buy this compromice cannot be predicted on time by cell behavior history (capacity, esr, temps and unexpected changes on their charts.) It's of course a matter of priorities of the industry. S.M.

...or towards a hostile military target, perhaps.

. . . like at hostile targets in the Ukraine using stand-off deployment methods.

https://auto.economictimes.indiatimes.com/news/two-wheelers/scooters-mopeds/heat-wave-on-ev-fires-raging-industry-in-a-huddle-shaken-not-stirred/90631751

https://www.deccanherald.com/business/what-s-causing-fire-in-electric-vehicles-1097381.html

..."There have been at least thirty deaths involving incidents of Tesla car fires.^[74 "...

https://en.wikipedia.org/wiki/Plug-in_electric_vehicle_fire_incidents

How many must die before it's regarded as a serious problem?

If you would monitor the internal resistance and temperature of the battery pack, or preferably the batteries individually, then you could increase cooling on demand when needed...an isolation method for failing batteries would reduce the incidence of failure by thermal runaway even further...when a cell starts to overheat repeatedly or the internal resistance hits a certain point, it could be isolated from the pack, thus providing a safer and longer life for the pack, as well as providing for individual failed cell replacement....

..."The aged cells shown more probabilities of thermal runaway due to the increase of the internal resistance. However, it is possible to reduce the difference by increasing the cooling flow from 3 g/s to 50 g/s. "...

"Thermal runaway evaluation and thermal performance enhancement of a lithium-ion battery coupling cooling system and battery sub-models"

https://www.sciencedirect.com/science/article/abs/pii/S1359431121013089#!