Dafo Vehicle Fire Protection has built a fire protection system which addresses and mitigates the new fire hazards associated with Li-ion batteries, as part of an EU initiative.

Fire suppression systems for vehicles have been on the market for decades, and are widely used and regulated across a wide variety of industries. However, these systems are tested to be effective on vehicles with combustion engines, and all test standards are designed with this in mind.

The growth of the electric and hybrid electric vehicle industry has accelerated the demand for new fire suppression technologies.

“With the rapid introduction of electric and hybrid electric vehicles in public transport, there are new challenges because they present completely different risk scenarios,” said Anders Gulliksson of Dafo Vehicle, coordinator of the EU-funded Li-IonFire (Automated e-vehicle Lithium Ion Battery Early Warning and Fire Suppression System) project.

A comprehensive solution for fire mitigation

“When the commonly used Li-ion batteries fail through short circuiting, overcharging, high temperatures, mechanical damage and overheating, this might cause thermal runaway and the release of a flammable electrolyte, which makes fire extinguishing very difficult. In addition to the dramatic fire scenario with the rapid increase in heat, there are a lot of potentially toxic gases being emitted”.

The project partners, including Dafo Vehicle Fire Protection and Sweden’s RISE Research Institutes, explored various techniques to detect potential battery failures as early as possible and take immediate action to halt, or delay, a potentially dangerous situation.

The partners studied the different fire risks associated with battery spaces, including specific risks when charging, and after-crash handling procedures for electric vehicles and batteries. They also investigated to what extent fixed and integrated fire suppression systems, which are widely used to protect engine compartments on heavy vehicles, can be applied to vehicles powered by Li-ion batteries, and how they should be designed.

Through extensive testing, the Li-IonFire team better understood how a breakdown occurs within the battery and how it can be detected.

“If a system is activated at this early stage, the battery can be ‘brought back’ to a safe state, without the fire developing further,” explained Gulliksson.

“The tests have also shown that even with a late deployment of the fire suppression system, there’s a possibility of delaying the battery reaching a critical state, meaning that the chance of safe evacuation is very high.”

With proper detection and system activation, the hazardous scenario can be reversed and potentially even stopped entirely.

An integrated solution for early fire detection, system cooling and fire suppression.

The project team has successfully validated and demonstrated an electric and hybrid electric vehicle fire protection system for electric and hybrid electric vehicles. The new system provides an early fire alarm and spot cooling system to prevent heat runaway while localising and suppressing fire. The system was officially unveiled at in 2019, and has generated tremendous interest from both end users and vehicle manufacturers.

“Li-IonFire delivers to the market a product that didn’t exist until now: a system that can offer real protection against battery fires, using a new suppression agent, Forrex EV, which is specifically developed for these applications,” concluded Gulliksson.

“Li-IonFire will significantly boost the safety of operators and the protection of valuable assets.”

Li-IonFire will be available from September 1, 2020.