September 28, 2022
Electric Vehicle (EV) fires are in the news. While vehicle fires are nothing new, there is a concern that EVs might be more prone to fires than ICE vehicles, even if recent studies with the limited data available do not support the concern. It is no debate, however, that when a lithium-ion battery from an EV catches fire, the fire presents unique challenges:
- An EV battery fire is a lot hotter (up to 4,900 degrees Fahrenheit compared to 1,500 degrees Fahrenheit),
- An EV battery fire takes a lot more water to extinguish (sometimes as much water as needed to extinguish a house fire), and
- An EV battery fire lasts a lot longer (over an hour in some instances)
“Lithium batteries are generally safe and unlikely to fail, but only so long as there are no defects and the batteries are not damaged,” according to a 2019 OSHA publication, entitled, Preventing Fire and/or Explosion Injury from Small and Wearable Lithium Battery Powered Devices.
With the rush to produce EVs for the masses, manufacturing defects will happen. One EV manufacturer recalled approximately 110,000 EVs in 2021 due to spontaneous fires that were believed to be caused by defectively manufactured batteries. Other EVs from other manufacturers have also been reported to spontaneously combust while driving, during charging, or after charging. For example, the Washington Post reported in 2021 instances where EV batteries have spontaneously combusted while parked and charging in consumers’ garages, causing both vehicle and house fires.
Of other concern, the batteries in EVs are at a significantly heightened risk of damage than other consumer products with lithium-ion batteries, making them more likely to fail. According to pre-pandemic statistics from NHTSA, the average number of reported vehicle accidents in the United States was 18,510 per day. As EVs on the roadways increases, there will be greater opportunities for EV batteries to become damaged, and for thermal runway to occur – even weeks after an accident. According to a 2022 Washington Post article, a firefighting agency had to extinguish an EV battery fire at a wrecking yard three weeks after a collision. To fully extinguish the EV battery fire, it took ingenuity (digging a water-filled pit for the fiery vehicle), nearly 4500 gallons of water (the same amount of water needed to extinguish a house fire), and over an hour.
What is thermal runway? When the EV battery is exposed to excessive heat, or there is a penetration in the battery case, an internal short circuit can occur, which can cause a vicious cycle. The heat causes a chemical reaction, which generates more heat, which makes the chemical reaction develop even faster, which generates even more heat. This process is called “thermal runway” and it is the chain-reaction process generating EV fires.
With the push for EVs in garages and on roadways, defective and damaged EVs will become more common at dealerships and service centers, and this will increase the risk of thermal runway and spontaneous fires at your facilities. Your facilities must be prepared, or it could spell disaster. Imagine the results if an EV spontaneously combusts while parked inside your building, or on a lift, in the middle of the night.
Inevitably, your facilities and employees need the proper policies, procedures, training, and equipment to combat and minimize EV battery fire dangers to your people and property. Get prepared, and seek the guidance of knowledgeable experts.