04.3 EV traction battery fire behaviour

A traction battery fire has unique characteristics

Earlier, we looked how it can be difficult to identify an electric vehicle from the blue 'EV' numberplate badge, or other external features.

Understanding how a traction battery fire progresses may assist in early identification, in order to establish the appropriate emergency response.

Interesting to note; an electric vehicle traction battery under 50% state of charge (SoC) is less likely to go into thermal runaway. Under 25% SoC is it unlikely the battery will go into thermal runaway or ignite.

We can also identify that an EV is involved in an emergency incident, by looking for traction battery fire characteristics

What are they & how do we recognise them?

When arriving at a vehicle fire, look for one or more of these signs that you might be dealing with an electric vehicle lithium ion traction battery fire.

EVFS Website EV Traction Battery Fires-9.png
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A dashboard fault code is often first indication of battery short circuit

Large cloud of dark & light vapour - highly flammable

Popping noises as cells vent & whistling/hissing noises as gas escapes

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EVFS Website EV Traction Battery Fires-8.png

Ignition of jet-like, directional flames at up to 1000 degrees celcius

Reduction in vapour cloud as it is consumed by flames

Increased fire activity & possible projection of debris

Watch: EV traction battery fire behaviour (volume on)

Video credit: Lawrence Choong

An electric Nissan Shuike on charge at a DC unit ignited, detroying four other vehicles.

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Dark cloud of heavy metal particles

Whistling noise of venting gases

Lighter vapour cloud above vehicle

Small vapour cloud explosion, vapour cloud is consumed

Jet-like, directional flames

Listen for popping noises, watch for debris projectiles in centre of the screen