As lawmakers around the world weigh bans of 'forever chemicals,” many manufacturers are pushing back, saying there often is no substitute.
One of their uses is in firefighting chemical fires.
When an electric car is on fire, you need PFAS to stop the lithium fire. Water just can’t stop it.
Of course, before batteries we used gasoline.
I imagine their might be more of these cases where modern technology relies on unsustainable practices.
Another factor that makes lithium-ion battery fires challenging to handle is oxygen generation. When the metal oxides in a battery’s cathode, or positively charged electrode, are heated, they decompose and release oxygen gas. Fires need oxygen to burn, so a battery that can create oxygen can sustain a fire.
Because of the electrolyte’s nature, a 20% increase in a lithium-ion battery’s temperature causes some unwanted chemical reactions to occur much faster, which releases excessive heat. This excess heat increases the battery temperature, which in turn speeds up the reactions. The increased battery temperature increases the reaction rate, creating a process called thermal runaway. When this happens, the temperature in a battery can rise from 212 F (100 C) to 1,800 F (1000 C) in a second.
Just because PFAS is one way doesn’t mean there aren’t other things that would work.
So for electrical fires, they use carbon dioxide to smother the fire and sodium bicarbonate to aid in putting it out, along with class c fire extinguishers. Class c are just carbon dioxide.
For chemical fires, carbon dioxide extinguishers are also used. They can use extinguishers with bromochlorodifluoromethane, aka Halon 1211, (which I guess could be a pfas chemical, but I don’t find anything either way).
