Electric vehicle lithium-ion battery fires present new challenges for firefighters

When a Tesla burned in East Marion after a head-on crash last month, gray smoke billowed into the night and flames rose 15 to 20 feet. Two occupants remained trapped inside as volunteer firefighters blasted water onto the crashed car.

It took three fire tankers, two pumpers and two hours to get it under control, fire and police officials said.

“The flames were a lot more intense, and the heat given off was a lot more intense" coming from the Tesla, Southold Police Chief Martin Flatley said.

The people inside the Tesla died, as did two people inside a Ford Explorer involved in the collision. 

The Tesla blaze laid bare a unique set of challenges faced by first responders battling lithium-ion battery car fires, which burn hotter, emit more smoke and require more water to extinguish, local and state fire experts said.

“They [lithium-ion batteries] burn differently than anything else that we've dealt with in the past, such as your standard combustibles in a home or your standard car fire,” said Michael Uttaro, Nassau County chief fire marshal.

Though electric vehicle fires remain rare, according to experts, first responders are undergoing training and seeking new tools as the cars' popularity has exploded.

The state has 136,587 electric cars, more than three times as many as in 2019, according to Atlas Public Policy, an EV research firm. Last year, electric vehicle sales grew 65% nationwide compared with 2021, according to Cox Automotive, a research and consulting firm. 

Most all-electric vehicles and plug-in hybrid electric vehicles use lithium-ion batteries, according to the U.S. Department of Energy.

Few countywide EV fire stats

Uttaro said the office started tracking lithium-ion battery fires in cars and other devices in September. Since then, there was one electric vehicle fire and four other fires sparked by lithium-ion batteries in Nassau County, including one that was fatal. Suffolk’s Department of Fire, Rescue & Emergency Services does not maintain countywide statistics, according to a spokesman.

Because there aren't as many electric vehicles on national roadways and there's a small crash sample size, it's unclear whether EVs are more likely to catch fire compared with gas-powered vehicles, according to National Highway Traffic Safety Administration officials.

Lithium-ion technology is challenging firefighting methods that have been used to put out gasoline engine fires for more than a century, fire experts said.

John D’Alessandro, secretary at the Firefighter Association of the State of New York, which has 45,000 members, called the potential dangers “a very big deal,” and hopes that with experience, firefighters will learn more effective tactics.

“Hopefully it teaches us how to put a solution to the problem as quickly as possible," said D'Alessandro, who is also a firefighter in Saratoga County. He said laws and regulations are needed to improve safety around lithium-ion batteries.

Andrew Klock, senior manager of Applications and Development at the National Fire Protection Association, said firefighters need to know what to target on an electric vehicle fire, rather than just using more water.

“You don't just pour water on the engine compartment for instance, you don't pour water on the top of the car. What you need to do is use water effectively and get it where the battery is or in close proximity,” Klock said.

Joe Agovino, special assistant to the commissioner at Suffolk Fire, Rescue and Emergency Services, added that there has been ongoing lecture training across the county since 2021.

"Our training will continue to evolve as we continue to provide education on this matter as new info is provided via our website," he said in an email.

Most electric cars are powered by lithium-ion battery packs comprised of thousands of cells encased in a hard shell that is usually attached to the car’s undercarriage. Firefighters can have a difficult time accessing the battery compartment and cooling it, requiring more resources, including more manpower and additional engine companies, thousands more gallons of water and more time to combat, Nassau County fire officials said.

“These battery fires burn from the inside out, which is why it's so difficult to extinguish those fires. Because you can't get the water inside the battery, the fire originates internally inside the battery,” said Michael Mennella, hazmat specialist at the Nassau County Fire Marshals Office. “On a normal fire, you would apply water to the surface and we'd be able to put the fire out … that's why we can't put the fire out so easily.”

He said the additional time it takes to fight the fires could potentially strain resources.

When one cell inside the battery pack overheats and ignites, it creates a chain reaction called thermal runaway, in which higher temperatures start to impact adjacent cells, causing the fire to spread internally. There is also a risk the pack will reignite hours or days after being extinguished due to "stranded energy" that can linger inside, according to the National Transportation Safety Board.

Fires aren't the only challenge firefighters face with electric vehicles.

During emergencies, firefighters may sometimes have to cut vehicles to extricate victims, but there are electrocution dangers in designated areas of electric cars, and firefighters have to be familiar with each car, D’Alessandro said. Each manufacturer has a safety response guide for different models that includes information about high-voltage areas. The Tesla model 3, for example, has “no-cut” zones due to high voltage, gas struts, or other dangers.

'Outside the box'

Greenport Fire Department Second Assistant Chief Craig Johnson said that to stay proactive, firefighters underwent training early last month. The department is also considering whether to purchase blankets made of special material to smother the fire. Another tool being considered is a "cellar hose head" that slides under the vehicle and sprays water.

"These vehicles force you a little bit outside the box,” Johnson said.

Another potential risk is saltwater flooding. After flooding in Florida from Hurricane Ian in September, 12 EV fires were reported in the following weeks.

Residual salt in the battery can lead to overheating. In Freeport last December, a Tesla EV caught fire after a flooding condition, according to the Nassau Fire Marshals Office. There were no injuries. 

So far, the data shows non-crash fires are rare for EVs, but the likelihood increases as they age, according to Joe Young, a spokesperson at the Insurance Institute for Highway Safety. He also added that given the young age of EVs and relatively small number, it's likely too early to draw firm conclusions about whether they are more likely to spontaneously catch fire.

Rosemary Mascali, chair of the Education & Outreach Subcommittee at Drive Electric Long Island, a coalition of stakeholders, said electric car fires occur less frequently than in gas cars, whether involved in crashes or not. Tesla, she said, reported five car fires per billion miles driven, compared with 55 fires per billion miles driven in gas-powered cars.

As the number of EVs continues to grow — state regulations mandate that all vehicles sold will be zero-emissions by 2035 — first responders want to make sure they're ready for the change.

The EVs will cause fire safety experts "to up our game to try to meet the challenge of what these devices do when they go on fire,” Uttaro said.