NTSB: Electric vehicle battery fires a threat to first responders

The National Transportation Safety Board (NTSB) on Wednesday said that electric vehicle fires pose a threat to first responders and that vehicle manufacturers have distributed inadequate guidance to mitigate safety risks. 

In an 80-page report based on an investigation on four electric vehicle fires, the NTSB found that the vehicles’ high-voltage lithium-ion batteries “pose the risk of electric shock to emergency responders from exposure to the high-voltage components of a damaged lithium-ion battery.”

The government agency added that its investigation found that damaged battery cells can experience uncontrolled spikes in temperatures and pressure. 

“The risks of electric shock and battery reignition/fire arise from the ‘stranded’ energy that remains in a damaged battery,” the agency said.

NTSB also examined national and international safety standards for electric vehicles, including guidance documents vehicle manufacturers provide to first responders. The agency found that the current standards and research related to electric vehicle batteries contained significant “gaps.” 

NTSB, which has no enforcement powers and can only make recommendations, called for manufacturers to develop and publish vehicle-specific response guides for addressing battery fires and limiting chemical thermal runaway and reignition. NTSB added that the updated guidelines should also include information on how to safely store vehicles with damaged lithium-ion batteries.

The findings come as automakers are increasingly releasing electric vehicle models as a more environmentally friendly alternative to gasoline-powered cars. 

The NTSB’s investigations of electric vehicle fires began following crashes in Lake Forest and Mountain View, Calif., and Fort Lauderdale, Fla., in 2017 and 2018, as well as a non-crash fire in West Hollywood, Calif. 

Three of the batteries reignited after fires were initially extinguished by first responders. 

All four vehicles involved in the NTSB investigation were made by Tesla, the top-selling electric vehicle manufacturer in the U.S., which as of Wednesday has a market value of approximately $809 billion. 

In the 2017 Lake Forest fire, a Tesla Model X’s battery caught fire after it crashed into a garage. NTSB engineer and highway investigator Thomas Barth said in a video published Wednesday that firefighters poured thousands of gallons of water on the vehicle in an attempt to put out the blaze. 

“They didn’t realize that they had to direct water onto the battery compartment under the car to cool the battery and stop the reaction causing the fire,” Barth explained.