Frequently, electric cars are associated with a higher risk of fire compared to fossil-fuel vehicles. But in fact, the very opposite may be true. Nevertheless, serious consideration must be given to the other risks associated with electric vehicles and their batteries.
“Electric cars in parking lots keep catching fire” “Fireman: Electric cars are one of the biggest dangers we face right now” “Tesla vehicle blamed for major fire that destroyed hundreds of cars”
As electric cars have become more common over the years, so have headlines like these. But, according to Ola Willstrand, Project Manager at RISE, there is no clear evidence of there being a higher risk of fire with electric cars compared to fossil-fuel vehicles. In fact, the risk might even be lower.
“Car fires are frequently caused by a leakage of flammable liquid or gas, which ignites on a hot surface. There aren’t any such liquids in electric vehicles, thereby eliminating that risk. With hybrids, however, the risk remains,” he says.
Fire at Stavanger Airport
Early in January of this year, news spread around the world that an electric car had caused a major fire and collapse of a parking garage at Stavanger Airport. The police later refuted that claim, stating that the fire had actually originated in an older model diesel car.
“The first reports in media tend to be exaggerated or even false. I don’t know anything more about the fire at Stavanger than what was reported in the news. It’s unfortunate, however, that a quick first response was hampered by the rumour and fear of a fire in an electric vehicle,” says Ola Willstrand.
Type of battery matters
Perhaps the biggest reason why electric vehicles are perceived as being a greater fire risk is that they are run on lithium-ion batteries, which have caused things like mobile phones and hoverboards to catch on fire or even explode. But not all batteries are the same. When it comes to safety, the type of battery really matters.
“Battery design in the automotive industry is typically better, with higher requirements on testing, along with higher-quality safety systems,” says Ola Willstrand.
The reason for fires involving electric cars is typically associated with something other than the battery. From a safety perspective, however, it is still an important matter because burning batteries emit toxic fumes.
“Because the battery is typically located low down in the car, it is somewhat protected if the car catches on fire. Tests have shown that it often takes more than 30 minutes, with the vehicle fully engulfed in flames, before the battery is involved,” he says.
Not more dangerous, but different
In other words, it would be incorrect to conclude that there is a greater risk of fire with electric cars or that the risks are greater if they do catch fire. The risks are, however, different. If lithium-ion batteries short-circuit, cells can enter a state known as "thermal runaway," in which they continue heating up to a point where they can eventually ignite. It is difficult, however, to assess the status of a battery and they typically catch fire long after the initial damage has occurred. Because of that, recycling also involves certain risks.
All of this puts new requirements on knowledge and guidelines. RISE is working to both generate and spread such knowledge.