Lithium-ion (Li-ion) batteries are indispensable in our society. Everyone has nowadays devices with Li-ion batteries: mobile phones, laptops, hoverboards, cars, bicycles, Energy Storage Systems (ESS), etc.
There are regular reports about fires involving Li-ion batteries. In most cases, the reporting is only about the fire itself and not about the hazardous substances that are released during these fires. Certainly with electric cars it is mainly about how difficult it is to extinguish a fire from such a ‘battery-car’. The consequences of fire for our safety and health usually remain underexposed and that while this risk is certainly present. This is evident from the fire in (Drogenbos, Belgium) where tests are being carried out with energy storage systems, and more than 50 people became ill due to the substances released during the fire.
But what makes a battery fire so special?
Voltage effects, charging with the wrong voltage and/or temperature effects can cause a Thermal runaway in the battery. A thermal runaway is a self-reinforcing process in which the temperature continues to rise, (chemical) materials in the battery are broken down, resulting in an internal short-circuit that results in the combustion of the chemicals in the battery.
The following toxic pyrolysis products are released during combustion:
- hydrogen fluoride (highly corrosive acid);
- lithium oxide (causes burns);
- hydrochloric acid (causes burns and irritates the respiratory tract).
The issue that arises with the ever-increasing application of Li-ion batteries is, on one hand, the danger of a self-sustaining fire, and on the other hand the great health risk due to the released toxic substances in the air and in the fire extinguishing water.
Imagine what that could mean in underground parking where a (large) number of parking spaces for electric cars are clustered.
A fire or, in which case, a thermal runaway in one of these cars is not only very difficult to extinguish, there is also a good chance that more and more (electric) cars will start burning for a long time and the fire will become increasingly difficult to fight. The property loss risk is, therefore, increasing enormously, not to mention the health risks for the environment.
These health risks also apply to the large-scale application of batteries at events, local batteries, storage of solar energy, etc.
The increasingly large-scale application of Li-ion batteries, therefore, poses considerable challenges for society and calls for the abandonment of traditional fire safety solutions to enable the application of innovative solutions.
Nothing is impossible, but it requires a different way of thinking about fire safety!
Gerben van Hal