Driving Future Mobility
April 27, 2022
Driving Safety for Electric Vehicles
Mike Hale, Global Plastics Technology Director
Electric vehicles (EVs) are the future of transportation, enabling us to reduce our dependency on fossil fuels thereby decreasing our impact on the environment. As EVs grow in popularity though, we must evaluate how safety standards must change before they become mainstream.
A recent incident occurred in the transportation of EVs across the Atlantic Ocean, where several batteries caught fire. The crew needed to be evacuated because the fire could not be extinguished. Instead, the ship eventually sank from the damage. This incident leaves us questioning whether today’s safety standards and infrastructure appropriately account for the unique properties of EV battery fires.
We need to consider how these battery fires will impact fire suppression, the equipment needed to battle them, and infrastructure upgrades.
Slow the Fire from Spreading
As plastics start to be considered as a potential solution for battery cases, Trinseo and other materials providers need to explore solutions that could help slow EV fires from spreading. When lithium-ion (Li-ion) batteries catch fire, they burn slowly—the heat builds over time before flames appear.
Therefore, materials should be adapted to slow the fire further by encapsulating the battery to help passengers evacuate. While metal could achieve this, it would add weight to the vehicle. At Trinseo, we are evaluating polycarbonate/acrylonitrile butadiene styrene (PC/ABS) resins as an alternative since they have a good balance of heat, ignition, and impact resistant performance, as well as being typically ductile at low temperatures.
When Fire Happens
In addition to containing EV battery fires, we must also ensure our infrastructure is equipped to handle them. How do we adapt car parks and garages for EV fires, which burn longer and hotter than combustion fires and could require special fire suppressant foam?
Underground car parks are required to be fire resistant; however, those standards are for combustion engines. If we imagine a car park as it stands today—sometimes hundreds of vehicles—would it withstand a large EV battery fire? While EVs are less likely to catch fire than traditional vehicles—a recent study found 25 EVs catch fire per 100,000—EV fires are significantly more destructive than their combustion engine equivalents.
Currently, industry standards for EV fires are in early stages, and they do not focus on materiality concerns. More needs to be done as today’s practices for vehicle fires will not suffice.
EVs are not the first transportation technology to require updated safety and infrastructure standards. Trains and airplanes underwent similar discussions; however, these changes often followed disasters, such as the King's Cross St Pancras tube station fire in 1987, which resulted in 31 deaths and over 100 injuries. This incident pushed London to upgrade their fire-resistant materials in Underground construction and overhaul stations to remove wooden escalators. Additionally, trains now have different fire safety measures based on where they are traveling, such as through fields, tunnels, or even underground in major cities. Tunnel construction is specifically designed to withstand heat from high-speed trains.
We need to have these conversations now, before tragedy strikes, so we can preserve life and improve materials and infrastructure. Governments, OEMs and insurance companies must develop progressive EV fire and safety guidelines like those in place for other modes of transportation. While EVs are the future, and offer us wonderful sustainable alternatives to fossil fuels, we need to be ready for the new challenges that will come with them, before EVs are the mainstream family vehicle.