Renault's trying to do with EV battery fire safety what Volvo did with seatbelts

Someone give Renault a gold star, or ten. The carmaker has made its 'Fireman Access' patents freely available to the car industry in a move reminiscent of Volvo’s 1959 seatbelt-design sharing.

The Fireman Access system enables firefighters to rupture the protective membrane around an EV or plug-in hybrid’s battery pack and douse the thing in water, pronto. The mechanism is a button that can be pushed with the pressure of the water hose.

In figures published by QBE last May, there was a 33 per cent increase in electric car fires in the UK between 2022 and 2023. Relatively speaking these numbers (89 to 118 incidents) are low, not just in light of the increasing number of EVs and PHEVs on the roads, but also when compared to fuel-related fires. Want the stats? In 2022, of the 18,991 UK road vehicle fires, only 239 were battery-related.

Though car fires are usually down to dodgy fuel systems, EV batteries can cause more dramatic fires and are more difficult to deal with. It’s all to do with something called 'thermal runaway'. Basically, the battery short circuits, overheating and releasing highly flammable gases which ignite. It’s dangerous since it only takes one cell to start it, then the others contagiously follow suit. Not good.

To date, the Fireman Access and Renault's SD switch – which acts like a fuse to decouple the car's electrics from the battery pack (which has also been developed with firefighters) – has helped cut the response time in dealing with electrified vehicle battery fires from hours to minutes, in turn enabling Fireman Sam to get back in his truck and onto the next emergency.

Renault boss Luca de Meo said: "Fireman Access is a practical demonstration of what can be achieved by combining our expertise as a manufacturer with the skills of the men and women who keep us safe every day. 

"I'm delighted to be making this innovation freely available, because when it comes to a subject like safety, we need to break down all the barriers. This move is also in keeping with the commitment made alongside the United Nations, to make mobility safer, all over the world."

The carmaker hopes all seven patents – already available on Alpine, Dacia, Mobilize and Renault models – will get adopted by other carmakers and create a standardised safety feature going forward.

Like that wasn't enough, Renault's also used its work with firefighters to train them to be more aware of how modern cars are set up using virtual reality workshops. Like we said, gold stars at the ready.

Renault isn't the only one looking at ways to deal with overheating batteries though. A division of Stellantis US had a patent approved for an EV exhaust recently. The idea there is to vent the gases, e.g. hydrogen, that could combust, while simultaneously releasing the pressure that could create heat.

With lithium-ion batteries being used in other mobility devices, such as e-scooters, there's also scope for the safety standard to reach a broad base.