Electric vehicles (EVs) have been around for more than 20 years. Once a niche vehicle, EV sales have greatly increased over the past decade. Although EVs account for less than two percent of all vehicles on U.S. roads, the U.S. saw EV sales of over one million in 2023, up 56 percent since 2022. However, misconceptions and highly publicized EV battery fires make EVs appear more dangerous than gas-powered cars.

First, let’s explain what classifies an EV. According to the U.S. Department of Transportation:

  • Battery Electric Vehicles (BEVs) or all-electric vehicles runs entirely off of electricity from a high voltage (HV) battery. BEV batteries are charged using external Level 1, 2 or 3 chargers.
  • Plug-In Hybrid Electric Vehicles (PHEVs) use an internal combustion engine (ICE) and HV battery to power an electric motor. PHEV batteries are charged using the ICE or external chargers.
  • Hybrid Electric Vehicles (HEVs) rely on a combination of an ICE and a HV battery to power the vehicle. HEV batteries are charged via the ICE or regenerative braking.
  • Fuel Cell Electric Vehicles (FCEVs) are still new to the market and use an electrochemical process to convert hydrogen into electricity to power an electric motor. Currently, FCEVs only charge their HV battery using on-board compressed hydrogen gas.

Ahead, we’ll look at the data and with the help of veteran firefighters and other experts in the field explain everything to know about EV fires.

What Is an Electrical Vehicle Fire?

According to certified firefighter Jack Bishop, an EV fire is “a fire incident involving an EV, primarily originating from its lithium-ion battery pack.” These fires can result from thermal runaway, a condition where an increase in temperature leads to a self-sustaining chemical reaction or short circuit, causing the battery to overheat and ignite. Associate Clinical Professor of Fire Protection Engineering William Koffel notes that “the EV could be the first item ignited, or the fire could spread to the EV.”

Causes of EV Fires

Everything To Know About Ev Fires Gettyimages 1440243847GENESIS KORAWEE RATCHAPAKDEE/GETTY IMAGES

According to a 2020 NTSB report and third-generation firefighter Lauren Jones, the major cause of EV battery fires happen after the HV Lithium-ion battery malfunctions after a crash. During crashes, HV battery packs can be “punctured, or damage to high-voltage wiring and cables can cause short circuits,” says Jones. “Sparks from a short circuit can ignite the battery’s highly flammable organic solvents, setting individual cells ablaze, which then overheat, igniting other cells,” said Bishop. Jones also stated that if an EV is in a flood, “the [HV Lithium-ion] battery can dry out, causing it to overheat and ignite.”

According to a 2024 study published in Science Direct, even salt spray can cause an EV battery to self-ignite, with the likelihood of ignition increasing with exposure time to the spray and the age of the vehicle.

The other major cause is thermal runaway. According to UL Research Institutes, thermal runaway results in “an extremely high, uncontrollable temperature and violent venting of flammable gasses” that can rapidly ignite. Poor battery design, poor ventilation, vibrations, damage to the battery, overcharging, a malfunctioning battery management system, lack of maintenance or charging a battery before letting it cool down can all trigger thermal runaway.

Steve Lockwood, owner of Mountain State Fire Protection LLC, adds, “Using damaged or incompatible chargers, faulty aftermarket modifications [light packages, high-powered radios] and living in climates with extreme temperatures all increase the risk that could ignite [the high voltage battery] causing thermal runaway.” This phenomenon affects all Lithium-ion batteries, including those in your smart phone, electric toothbrushes, power tools and other devices.

What To Do If Your EV Catches Fire

If you’re driving, pull off the road to a safe location as quickly as possible. Get out of the car and run on the median or shoulder not in the traffic lanes and CALL 911! According to Lockwood, you should inform the 911 dispatcher of your location and the car is an EV. “Never attempt to extinguish the fire yourself. EV fires burn hotter, burn longer and are more complex than a conventional ICE vehicle fire.”

According to Chief Palmer Buck of The Woodlands Township in Austin, TX, “firefighters also need special training on how to safely disconnect and disable an EV HV battery and the proper techniques needed to quickly cool down a burning EV.”

How To Prevent EV Fires

Bishop recommends to “only use manufacturer-supplied or approved charging chargers and cables.” Other steps to prevent EV fires include:

  • Avoid overcharging and leaving the charger plugged in unnecessarily.
  • Schedule regular maintenance, including checking or changing EV HV battery coolant fluid and routine inspections, to ensure the battery’s thermal management and electrical systems are in optimal working condition.
  • Charge the vehicle in a dry, well-ventilated area, away from flammable materials.
  • Flush the battery/undercarriage with cold, clean water after driving in areas where salt is used during winter months, and have your repair shop clean corrosion or oxidation from battery terminals and other electrical connectors.
  • Check if there are any manufacturer recalls related to battery or electrical components.

How to increase EV battery life that will also prevent EV fires

  • Daily monitor the battery’s condition.
  • Power down if the HV battery warning light comes on.
  • Check charging system health using your vehicles built-in interactive visual tools to monitor energy usage details; high voltage power flow; charging status; HV efficiency history.
  • Keep the battery between 20 and 80 percent charged. Charging to 80 percent then disconnecting the charger leaves room for charging from regenerative braking, reducing the likelihood of overheating.

FAQ

Are electric vehicle fires more common than conventional car fires?

No, according to the International Fire and Safety Journal. Using data from the National Transportation Safety Board (NTSB), Bureau of Transportation Statistics (BTS) and government recall information, AutoinsuranceEZ indicated fires by vehicle type are as follows:

  • Hybrids signified the most, with 3,475 fires per 100,000 vehicles. This is most likely because hybrids utilize two powertrains.
  • ICE vehicles caught fire substantially less often, at 1,530 incidents per 100,000 vehicles.
  • EV fires were significantly lower than the others, with 25 fires per 100,000 vehicles.

Koffel added, “At this time, there is no indication that EV fires are more common than conventional car fires.” However, Lockwood notes, they are “usually more powerful when they happen. I would not tell anyone that [EV fires] are common.”

Are electric vehicle fires more dangerous than conventional car fires?

Yes. Thermal runaway causes temperatures of a Lithium-ion battery to reach almost 1900F, while a traditional gasoline power vehicle fire burns at around 1400F. According to Buck, his department “can extinguish a gasoline-fueled car fire with 500 gallons of water they carry on their trucks.”

However, Buck adds that “it can take 3,000 gallons or more to extinguish an EV battery fire.” In addition, due to residual heat, ongoing chemical reactions or EV battery design making it difficult for water or fire suppressants to reach all affected cells, EV HV batteries can reignite hours—or even days—after the initial fire is extinguished. According to Blaze Stack, “EV fire protocols are still evolving,” including the use of thermal imaging cameras that “detect residual heat in battery packs” as well as other firefighting methods and technologies.

What is an EV fire blanket?

“EV fire blankets will delay the development of the fire, will keep the fire from spreading to adjacent vehicles, or will smother the fire,” says Koffel. Made from fiberglass or silica-based fabrics, these blankets can withstand extreme temperatures.

A fire blanket specifically designed for EV fires can weigh up to 100 pounds and can easily take two or more people to properly place the blanket into position. “There is also concern that in some instances the [fire] blanket could trap vapors potentially resulting in a vapor explosion,” adds Koffel. So, leave extinguishing EV fires to professional firefighters.

Experts

  • William Koffel is an associate clinical professor who specializes in fire protection engineering with the A. James Clark School of Engineering at the University of Maryland. He is the former president of Koffel Associates, a fire protection and life safety engineering design and consulting firm, and he is recognized as an expert in the fire protection and life safety aspects of codes and standards. He is also a past president of the Society of Fire Protection Engineers (SFPE) and a former code official with the Maryland State Fire Marshal’s Office.
  • Lauren Jones is a 3rd generation firefighter with over 13 years of service with Willow Grove Volunteer Fire Co., holding the ranks of sergeant and lieutenant for five years. She still responds to fires for the Enterprise Fire Co. of Hatboro, PA. Lauren is currently serving as a Protective Services Teacher at North Montco Technical Career Center, Lansdale, PA.
  • Jack Bishop is recent to the firefighting profession, but has received several international accreditations and certifications from the U.S. Federal Emergency Management Agency (FEMA), The World Health Organization (WHO) and FireRescue1 Academy and U.S. Fire Administration (NFA).
  • Steve Lockwood is owner of Mountain State Fire Protection LLC, which specializes in premier fire equipment and comprehensive fire protection services.
  • Palmer Buck is the Chief of The Woodlands Township Fire Department in Austin, TX. Chief Buck Chief Palmer Buck holds a Bachelor of Arts in Applied Science Fire Protection Technology, a Master of Public Affairs and is a graduate of the National Fire Academy’s Executive Fire Officer program. Chief Buck has 37 years of experience in public safety. He is a proven leader with extensive operations and command experience, and a sought-after mentor and advisor to firefighters of all ranks. He is a member of the International Association of Fire Chiefs, the National Fire Protection Agency, the National Society of Executive Fire Officers and the International Association of Firefighters. Original interview notes from “Are Electric Vehicles More Likely To Catch on Fire?” Apr 23, 2023.

Resources

RELATED:

Author
Bob Lacivita
Since rebuilding his first engine at age 14, cars have been Bob Lacivita's passion, as well as his way of life. He went on to become an award-winning ASE and General Motors auto technician, vocational educator, career and technical center administrator, technical consultant and freelance writer; teaching legions of students and readers about DIY ca...
Read More
Bob Lacivita