Clearing the Air: Emerging Data and Battery Trends Suggest EVS Could Bring Lower Fire Risk
Emerging data tells us that electric vehicles (EVs) don’t have any higher fire risk than conventional combustion engine vehicles. According to Andrew Klock, senior manager of education and development at the National Fire Protection Association, EVs are “not more dangerous. They’re just different.”
EV battery fires involve thermal runaway, a chemical process that occurs when one of the cells in a battery pack short circuits and heats up unsafely. The heat from the malfunctioning cell can cause the adjacent cells to fail, and this can lead to a chain reaction in the battery pack. Compromised battery cells release oxygen that fuels a fire during thermal runaway. This can be slowed and eliminated by lowering the temperature enough to make the chemical process stop. Directly targeting the battery pack with water to gradually lower the temperature stops EV fires. Currently, it can take around 2,500 gallons to extinguish an EV fire; a combustion engine fire can take about 500–1,100 gallons.
Thermal runaway is more common in certain battery chemistries than in others, and lithium-ion batteries made with nickel manganese and cobalt oxide (NMC) cathodes have relatively greater fire risk than other chemistries. But there’s good news here: The battery industry is shifting toward nickel- and cobalt-free lithium iron phosphate (LFP) cathodes and LFP batteries have high thermal stability that makes them less prone to thermal runaway. Assuming the shift continues, EV fire risk will be reduced over time. Next-generation, solid-state batteries currently in development promise to reduce EV fire risks even further by replacing flammable, liquid electrolytes in lithium-ion batteries with non-flammable, solid electrolytes.
According to data collected by EV FireSafe, an Australian company that monitors EV fires, there were slightly more than 500 battery-related fires in light-duty EVs globally between 2010 and the end of June 2024. With an estimated 40 million EVs operating globally as of early 2024, that’s around a 1 in 100,000 rate of fire. Tesla estimated that one of its vehicles caught fire every 130 million mi (209 million km) traveled, which is about one fire every 23,400 round trips from New York to Los Angeles. In comparison, the National Fire Protection Association estimated that a fire occurs once every 18 million mi (29 million km) for all fuel types, which is more than 7 times more frequent.
https://theicct.org/clearing-the-air-evs-could-bring-lower-fire-risk-oct24/