The Renault Group has developed a fire suppression system for electric cars that promises to drastically reduce the time and water needed to extinguish blazes – and it is now opening it up to other vehicle manufacturers. 

The Fireman Access system – fitted to all electric and plug-in hybrid Renault Group models – is said to allow electric vehicle fires to be extinguished "in roughly the same time as on a combustion vehicle". 

It takes the form of an adhesive disc that is placed over an opening in the vehicle's battery and is designed to dislodge under the pressure of a fire hose, which allows water to quickly spread to all the cells inside - "the only fast and effective way of stopping thermal runaway", according to Renault.

The company says this allows an electric vehicle battery fire to be extinguished in a matter of minutes, compared with several hours using current methods. It also uses 10 times less water.

Having rolled out the Fireman Access system to its current electric and PHEV models, the Renault Group is making the patents freely available via free licence to the wider automotive industry so other companies can use it themselves.

Electric vehicles are less likely to catch fire than combustion vehicles, but the fires are much more difficult to put out because a chemical blaze does not require oxygen, making suffocation ineffective and greatly increasing the amount of water needed to extinguish the flames.

A battery fire also releases toxic gases and can reignite without warning even after it has been extinguished – meaning burned-out EVs must be stored far away from other vehicles and buildings.  

Renault Group CEO Luca de Meo said: “Innovating to improve road safety is part of who we are at Renault. We're particularly proud of the partnership developed with the fire services in recent years. 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. 

"Today, 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."