Do EV Fires Make You Worry?

Dec. 28, 2023

More electric vehicles (EVs) are being sold than ever before and the EV charging infrastructure is being installed at a faster rate in home garages, public parking lots and even businesses like your own. Does this make you worry about the risk of EV fires? Should you worry? Let’s look at some facts.

According to U.S. government data, EV fires appear to occur less frequently than internal combustion engine (ICE) vehicle fires, with 25 fires for every 100,000 electric vehicles sold compared to 1,529 fires for every 100,000 ICE vehicles sold. Did you know that?

Is it a matter of age? According to an analysis by the National Fire Protection Association, vehicle fires caused 560 deaths, about 1,500 injuries and $1.9 billion in property damage in 2018, the last year I could find some data. The report includes all vehicle types. It did not differentiate between electric and ICE vehicles. The vast majority — 77% — of vehicle fires resulted from electrical or mechanical malfunctions.

Eighty-eight percent of highway vehicle fires involved models from 2007 or earlier. In other words, vehicle age and maintenance appeared to play a significant role in whether a vehicle catches fire. This raises an important question about EVs, which are newer. Will EVs have more fires as they age?

A fire at my shop

I started my shop in a rented two-bay garage. Within five years, we had our first and only car fire. A newly hired mechanic was welding the exhaust on my used 1977 Honda Accord and he started the rear floor carpets on fire. That lift never moved so slowly!

We were trained to push a burning car outside, if it was safe. We managed to do that, but the Honda was totaled. The Worcester, Mass., fire department showed up and I was humbled by the captain. Never again would I run a shop that was so unaware of the risks.

EV fires are different

While EVs may not catch fire as often as their ICE counterparts, when they do, they burn differently. EV fires burn hotter than gasoline. That means if an EV catches fire, it can pose a greater risk to objects around it.

EV fires also can reignite as the electrolyte has everything within it to burn. It needs no oxygen. The risk of reignition means that tire and service shops, towing companies or other entities that transport, service or garage a damaged EV could face a heightened fire risk as well. The key word is “damaged.”

A look at batteries

Years ago, high voltage (HV) battery packs were made using nickel metal hydride (NiMH) cells that were not flammable. Li-ion chemistries are now the norm in almost all HV batteries. And they can be flammable. With an EV, you are replacing the gas tank with a battery, so comparing the internal combustion engine’s fuel (gasoline) with electric vehicles' fuel (electricity) is a fair subject.

We know gasoline and respect it. Most tire stores keep a close eye on fuel leaks. The smell alone will warn us of the danger. Once you know how to handle these hazards, the better off you are.

Today’s lithium-ion batteries used in hybrid, plug-in hybrid and electric vehicles can burn or explode if they are defective or are physically damaged. That fact is well-known.

Automotive Career Development Center, my EV technician training company, has seven plug-in vehicles. We have inside and outside level I and II electric vehicle supply equipment (EVSE), which are commonly called chargers. Our understanding of the cells, modules and other components that make up HV battery packs helps lower the fear level, so we make no attempt to keep them outside. False evidence appeared real — or for short, F.E.A.R. — is usually caused by a lack of understanding.

Now, during a flood situation, there is a risk of an HV battery fire if the battery is in the vehicle’s cabin. Many hybrids and plug-in hybrids locate the Li-ion pack there. If the EV’s interior is submerged in salt water, as was the case in 2022 when Hurricane Ian hit Florida, watch out for smoke. Most long-range EVs have a watertight HV pack bolted under the chassis. The fire risk after saltwater flooding can potentially persist for weeks.

If a fire occurs while a vehicle is charging, it is usually within an hour of being connected to an EVSE or DC fast charger. That happens when impurities are in the cell or a spot-welded tab comes loose inside the HV pack. In almost every case, a recall is soon issued.

Get to know EV battery technology. There is a free two-part video series about Li-ion fires that we put together as a fundraiser to support foster teenagers. Go to https://www.fixhybrid.com/recorded-webinars/ and scroll down to the bottom and you will see First Responders FREE. Click there, scroll up and educate yourself. With understanding comes good decision-making. This certainly applies to EV service.

About the Author

Craig Van Batenburg

Craig Van Batenburg is MTD's monthly EV Intelligence columnist and the owner of Van Batenburg's Garage Inc. dba Automotive Career Development Center, which provides training for facilities that service - or want to service - electric and hybrid vehicles. For more information, see www.fixhybrid.com or email Craig at [email protected].