DETROIT (AP) – Fires in electric cars pose safety risks to first responders, and guidelines from manufacturers on how to deal with them have been inadequate, according to U.S. investigators.
There are also gaps in industry safety standards and research into high-voltage batteries with lithium-ion batteries, especially in rapid, severe crashes, the National Transportation Safety Board said Wednesday.
The agency, which has no enforcement powers and can only make recommendations, urged manufacturers to write vehicle-specific reaction guides to combat battery fires and limit chemical thermal run and re-ignition. The guidelines must also include information on how to safely store vehicles with damaged lithium-ion batteries.
The recommendations come at a time when carmakers are rolling out several new electric vehicle models, with many in the industry experiencing a turning point when switching from petrol to cleaner electricity.
In its Wednesday report, the agency also asked firefighters and auto-towing associations to inform members about fire hazards and how to deal with the energy left in the battery after a crash, and how to safely store a vehicle with a damaged battery.
And it asks the National Highway Traffic Safety Administration to include the availability of an emergency guide when calculating five-star car safety results.
NHTSA should also build a coalition to investigate ways in which batteries can be disconnected and reduce hazards from thermal runoff, a chemical reaction that causes uncontrolled battery temperature and pressure rises.
The NTSB began investigating battery fires following crashes and fires in Lake Forest and Mountain View, California and in Ft. Lauderdale, Florida, in 201
All four vehicles were manufactured by Tesla, the best-selling electric vehicle manufacturer in the United States.
“The risk of electric shock and resumption / fire from the battery is due to the ‘stranded’ energy remaining in a damaged battery,” the agency said.
In the August 2017 fire in the Lake Forest, a Tesla Model X battery caught fire after the vehicle left a road and crashed into a residential garage at high speed. Thomas Barth, an NTSB engineer and highway investigator, said in an agency video that firefighters poured thousands of gallons of water on the roof of the vehicle. “They were not aware that they had to direct water into the battery compartment under the car to cool the battery and stop the reaction that caused the fire,” he said.
In an 80-page report, the NTSB wrote that a review of emergency preparedness guidelines from 36 manufacturers showed that all had ways to reduce the risk of high-voltage shocks, including methods of disconnecting the battery. But none of the guidelines talked about limiting the risk of energy stored in the batteries, such as procedures to minimize re-ignition or instructions on where and how to spray water to cool the batteries, the agency said.
One way to deal with damaged batteries is to pull them out of the vehicle and soak them in a salt water bath to discharge the energy, the NTSB wrote.
The National Fire Protection Association, which offers training to first responders and traction companies, said it has already addressed most of the NTSB recommendations. Andrew Klock, head of new issues, says the group has released training on how to put out battery fires, then stick vehicles up and put out the batteries with water to limit resumption.
The NFPA has trained about 250,000 first responders, but there are 1.2 million firefighters nationwide, Klock said.
In a statement, NHTSA said last week it launched a battery safety initiative to address growing concerns about electric vehicle and structural fires ignited by batteries. Under the initiative, the agency will analyze data, investigate fires and monitor the investigation of electrical vehicle accidents, the agency said.
The Alliance for Automotive Innovation, a major automaker trade group, said it will review the recommendations and work with fire associations, NHTSA, the Society of Automotive Engineers and others to improve safety.
Messages were left Wednesday with requests for comment from Tesla and the National Fire Protection Association.