What happens if an electric car is involved in a crash and catches fire? An expert confirms some of the dangers and if carmakers are providing the right details for a safe rescue

The recent reports of electric vehicle (EV) batteries catching fire has reignited a commonly asked question - how safe are EVs really?

Lithium-ion batteries were first introduced in 1991 and have been used in our technology ever since. Most portable technology utilises them because of their storage capacity, longevity and because they're rechargeable.

They're in your mobile phone, tablet, laptop, toothbrushes, E-bike and some vape devices. They've been used comfortably and confidently for years – so why is there fear when you suddenly put one into a car?

This fear seems rooted in the fact that the batteries are large and powering one-tonne-plus vehicles that can be involved in accidents.

So, if an EV is involved in an accident, is there anything different that a first responder has to do to ensure their and/or the occupants safety compared to a traditional internal combustion engine (ICE)? According to Daniel O'Dea, Team Leader Alternative and Renewable Energy Technologies for Fire and Rescue NSW (FRNSW), an EV rescue does look a little bit different.

It seems obvious but EVs are extremely quiet, even when on, and it can be difficult for a responder to determine if the vehicle is on or off which can lead to there being "unexpected vehicle movement" which can endanger the responders and the occupant themselves during a rescue.

There are also additional hazards that are not present at incidents involving ICE vehicles. Like electricity hazards, leaking coolant or electrolyte from an EVs battery, as well as, "the potential to release toxic and flammable gas if the battery is damaged – this may lead to a fire or explosion".

But the hazard concerns are not limited to just the rescue of the occupants because if the battery has been damaged, stranded energy within the vehicle's battery "may also lead to a fire - days, weeks or even months after the initial incident".

But how often do these sorts of incidents occur? According to incident data from the FRNSW website, the first quarter of 2022 indicated that one in a hundred fire calls to FRNSW involved a battery in thermal runaway, which is when there is an uncontrolled and excessive rise in heat within a battery cell, often leading to cell venting and fire.

Considering the heightened risks in an EV rescue, it becomes even more important for first responders to be able to rely on up-to-date rescue cards, which is a two-page document that outlines a vehicle's structure and access points but, on an EV, also includes pertinent information on how to turn off the vehicle and "how to disable the vehicle's high voltage electrical system".

Yet, O'Dea highlighted that "most [not all] manufacturers provide a rescue card".

Standardising items like this should be a priority for manufacturers, to ensure the safety of their users and those tasked with rescuing them in the unfortunate event of an accident.

For the rescue cards that are available, how easy is it to access them?

FRNSW confirmed that first responders can access these cards through the ANCAP rescue app and that FRNSW "have now included this on the mobile data terminal in each fire truck allowing crews to search the licence plate to take them to the correct rescue card quickly".

This is not meant to scare would-be or current EV owners. The electrical components on EVs have to meet stringent safety measures for the Australian market and are relatively safe for everyday use. It's important to note that there is just more to EVs than the driving range and energy consumption to consider.

For example, how it can be difficult to declare a site safe and difficult to contain the fire from a damaged EV. There's also the question of how do you safely process and transport damaged EV batteries/cars when they can reignite months after supposedly being extinguished?

FRNSW are leading collaborative in-depth research on these items because there does seem to be a lack of guidance on standards, and legislation in relation to safety to address the potential risks from these emerging technologies (FRNSW website).

And with EVs leading the charge on a lot of car manufacturers future offerings, these questions need to be answered.