There are currently just over 700 electric-powered cars on Czech roads, but as their number grows, Czech firefighters are undergoing training in extinguishing fires in lithium-ion batteries. Incidents around the world show that while putting out a fire in a fuel-powered vehicle may take 10 to 15 minutes, a fire in an electric power car may take over an hour with an increased danger of re-ignition.
With the relatively small number of electric-powered cars on Czech roads, the country’s firefighters have little, if any, experience in putting out a fire in a car with a lithium-ion battery. These batteries are prone to a phenomenon known as “thermal runaway” – in which battery temperatures sharply increase to a point where they catch on fire or explode.
Construction engineers were aware of the danger and in order to lower the risk placed the battery low-down, enclosing it in a special “casing”. So, due to the location of the battery the danger of a fire breaking out is actually smaller than in a fuel-powered vehicle, but once it does, it takes much longer to put out and there is a danger of re-ignition hours after it has been extinguished. In some cases it can take 24 hours for a battery fire to be fully extinguished.
Experts at the Technical Institute of Fire Protection in Prague are developing new tools and tactics to help address the challenge and minimize the risks. Ondrěj Suchý, one of the specialists involved in the project explains:
“Firefighters have to get to the battery fast and then use appropriate extinguishers which will not just lower the temperature in the battery, but prevent it from reigniting.”
The institute is keeping its research under wraps and the project will be presented to the public in June, 2020.
Meanwhile, the country’s firefighters are being trained to respond to such a fire by conventional means, which means a huge amount of water and conventional fire suppression tools such as firefighting foam. They need to have experience in locating the battery and breaching the casing and once they have put out the fire, which may take an hour or more, cooling the battery to prevent it re-igniting. Special containers for electric-powered cars damaged by fire are being set up around the country to house the vehicles in the event of such an incident.
Despite these complications, experts say that battery-powered cars do have one important advantage. While a fire in a fuel-powered vehicle breaks out as soon as the fuel comes in contact with a spark or flame and then spreads rapidly, in battery powered cars it takes some time for the battery to achieve the heat necessary to start a fire – meaning that in the event of a serious accident the occupants of the car have more time to escape before a fire starts.