Extinguishing fires in electric cars

Burning electric car - how to extinguish it We keep hearing about burning electric cars in the news, and models from a well-known American manufacturer in particular have made the headlines several times. The burning car freighter "Fremantle Highway" in mid-2023 in the North Sea off the Dutch islands has once again shown how dangerous a fire in an electric car can be. However, this is not so much due to the frequency of burning electric cars (numerous studies show that electric cars do not burn more frequently than cars with combustion engines), but rather to the very special demands that a burning electric car, or rather the lithium-ion battery installed in it, places on the fire department and other first responders, and extinguishing it is often extremely challenging.

Extinguishing electric cars - the most important information in brief

The batteries in modern electric cars can store enormous amounts of energy and the fires that occur there have to be fought differently to those in classic combustion engines. Special extinguishing measures are required; currently, large quantities of water are often used, but the use of fire blankets for electric cars, for example, is more efficient and less costly. Extinguishing blankets can also be used where large quantities of water are not available or would cause damage to the surrounding area (such as underground garages, parking garages). Special care must be taken when disposing of electric cars afterwards. A similar problem - albeit due to the much smaller batteries - affects plug-in hybrids and hydrogen cars, which are also equipped with lithium-ion batteries.

Click here to go directly to the most important extinguishing agents for electric cars:

=> To the extinguishing blankets / fire blankets for electric cars

Detailed information on extinguishing electric cars can be found in the following sections.

Batteries in electric cars are the greatest fire hazard

In contrast to classic petrol cars, pure electric cars do not have any fuel in the form of petrol or diesel on board (plug-in hybrids / PHEVs do), which means that the fuel in an electric car cannot ignite in the event of an accident, for example. The danger with electric cars comes from the built-in high-performance battery, which can store increasingly large amounts of energy, especially in newer models, in order to provide the range desired by customers.

First of all: electric cars are no more dangerous than conventional combustion engines

At this point, it is important to mention that the impression should not be given that electric cars are more dangerous than classic combustion engines. With the increasing spread of alternative drive systems, the requirements for efficient extinguishing management are simply changing, especially for fire departments. With the necessary preparation and consideration of the new framework conditions when extinguishing electric cars, the fire department and private individuals are just as well prepared for this new situation as they are for possible fires involving classic cars and trucks.

Li-ion batteries are generally well protected

The lithium-ion batteries used in electric cars are generally fitted perfectly into the bodywork and protected by the manufacturers. In addition, the individual batteries are encapsulated, providing good basic protection for the batteries in the cars. Nevertheless, accidents in particular can result in such strong forces that individual cells or the entire battery area can be damaged, which can have various consequences, including the electric car catching fire.

How do you recognize a possible fire in an electric car?

Electric car fire - these are the first signs Unlike a classic car fire, a burning battery in an electric car is not usually characterized directly by flames shooting up, but begins with a thermal reaction in the battery cells. The temperature within individual cells rises, spreads to other cells and thus successively increasing temperatures develop and the dreaded thermal runway sets in, in which many (or all) battery cells react thermally in an uncontrolled manner and can catch fire. The first signs of a developing fire in an electric car are

Gases escaping from the battery block, often in conjunction with a hissing, whistling, etc.
Smoke development in the area of the battery block
Individual flames or sparks, often in combination with a corresponding odor
Rise in temperature over a longer period of time after the accident

Difficulty Time distance to the accident

One difficulty with battery fires in electric cars can be the distance in time to the actual accident. Even if the initial fire has been extinguished by the fire department, for example, a defective battery still poses a risk for much longer; sometimes even for days. In some cases, burning electric cars even have to be submerged in water-filled containers in order to control the long-lasting thermal reaction of the Li-ion batteries.

Extinguishing burning electric cars

Conventional extinguishing agents or normal car fire extinguishers are not very suitable for extinguishing electric cars. If an electrically powered car or truck catches fire, the fire department will inevitably have to be called out, as the electrical systems and batteries in the vehicles pose a significant risk to life and limb.

Professional firefighting is essential

Extinguishing blanket for electric cars Special battery fire extinguishers should at most be seen as a supportive measure, but their effect is rather negligible, especially with electric cars, battery-powered forklift trucks, etc., and their use is therefore not recommended - professional help is essential here, just as it is when extinguishing PV storage systems / battery storage systems. Accordingly, extinguishing electric cars focuses on two areas: Containing the fires or protecting the surroundings by cooling down the battery. While more and more fire departments are using special fire blankets for electric cars to contain fires, the efficient and predominantly long-term cooling of the battery of electric cars or plug-in hybrids continues to pose a major challenge. Ultimately, the defective batteries or the complete electric cars still have to be transported from the scene of the fire for disposal - another difficulty for many professional firefighters.

Real "extinguishing" of electric cars not possible

A special feature of lithium-ion batteries and therefore of electric cars is that the fire cannot be extinguished in the true sense of the word (as in a normal fire, for example), but due to the design of the batteries, this fire can flare up again for a long time (which is why electric cars, for example, are also sunk in containers after being extinguished, where the battery can then "die down" for a long time). Accordingly, firefighting with electric cars primarily involves containing the flames and the blankets are therefore not extinguishing blankets in the strict sense, but rather fire containment blankets. Nevertheless, the term "extinguishing" is also used colloquially here.

Measures for extinguishing electric cars

The following sections explain what measures professional firefighters use to extinguish electric cars and what downstream measures are necessary:

Currently often used by fire departments to extinguish electric cars: Lots of water

When extinguishing electric cars, the fire department often uses a well-known and tried-and-tested method: water. However, not only is the acute fire extinguished on site, but due to the very special fire characteristics of a battery, it must be extinguished / cooled more or less constantly, so that it is not uncommon for several 10,000 liters of water (!) to be used for a single electric car.

Difficulty: Limited water supplies on board fire-fighting vehicles

A problem quickly arises here: as the emergency vehicles only carry limited quantities of water, a supply via a hydrant is necessary. Even large emergency vehicles generally have no more than 1500 liters of extinguishing water or, if necessary, extinguishing foam on board. If a hydrant is not immediately available, even extinguishing a single electric vehicle can be a challenge. Accordingly, extinguishing an electric car on a highway, for example, where there are often no or only very few hydrants, can become a logistical challenge.

Special extinguishing lances should make extinguishing more efficient

In order to make extinguishing electric cars even more efficient, various suppliers are developing systems to reduce the amount of water required. The aim is to tackle fires quickly and efficiently with extinguishing lances or complete extinguishing systems specially developed for battery fires. However, these extinguishing systems are often not only cost-intensive, but also require special vehicle technology that is not available in every emergency vehicle.

"Decay basins" for electric cars - water-filled containers provide long-term safety

Recover-E-Bag_Electric_Car_Container_Alternative What was previously only known in the context of nuclear energy, the so-called decay pool, in which fuel rods can release the residual heat they contain over a long period of time, is also often used for the sustainable extinguishing of electric cars. Specially prepared containers are filled with water and the cars are submerged in them to prevent the battery from developing a fire again. As an alternative to the extinguishing containers for electric cars, there are other systems, such as a customizable Recover-E-Bag storage system, which is much more mobile and easier to use.

Conclusion: Conventional measures for burning electric cars only useful / available to a limited extent

As can be clearly seen from the above, conventional firefighting methods quickly reach their limits with high-performance batteries, so alternatives should at least be considered for the initial measures. More and more fire departments are therefore turning to special fire blankets for electric cars, which can be used to contain battery fires very efficiently without the need for vast quantities of water, thus gaining the necessary time to initiate further measures and minimizing the acute danger to the environment.

Fighting electric car fires with fire blankets / fire blankets

Fire blankets for electric cars are an effective way of containing burning lithium-ion batteries and thus minimizing the dangers posed by a lithium battery that has caught fire. The way the fire blankets work is as simple as it is ingenious: by spreading the blankets over the burning or fire-prone electric car, the fire-retardant material of the fire blanket prevents the battery fire from spreading to the surrounding area. Accordingly, the fire blanket does not extinguish the battery fire in the literal sense, but primarily prevents it from spreading to the surrounding area and ensures that the burning electric car causes greater damage. Manufacturers such as JUTEC, VLITEX and BRIDGEHILL have a range of extinguishing blankets / fire blankets for precisely these applications.

Flaring up and spreading to the surroundings is prevented

The cause of the fire, often a so-called thermal runway in the defective Li-ion battery of the electric car, cannot be extinguished, but the use of an extinguishing blanket prevents open flames and at the same time minimizes damage to the surroundings. At the same time, the fire blanket deprives the fire of oxygen, which also has a fire-fighting effect.

Extinguishing blankets create time for further countermeasures

In principle, the extinguishing blanket provides a "safe" environment in which the battery fire cannot cause any further damage to the environment, giving you sufficient time to initiate further countermeasures. In the case of electric cars, this can also mean that they are stored in so-called extinguishing containers until the danger posed by the Li-ion battery has been completely eliminated.

Securing transportation with a fire blanket

Extinguishing blankets are not only used for acute firefighting, but are also a sensible safety measure when transporting an electric car that has been involved in an accident - even if a fire has not yet broken out. If there is a risk of the battery of an electric car involved in an accident catching fire, a fire blanket can also be used as a preventative measure by using it when transporting the electric car involved in the accident.

Fire blankets as a quarantine measure for electric cars involved in accidents

After an electric car has been involved in an accident, it is usually stored at the breakdown site of a towing company or workshop in order to minimize the risk of a subsequent battery fire. Here too, fire blankets can be used as a quarantine measure to store the electric cars safely for longer periods of time. The advantage over the water-filled containers is on the one hand the lower price, but on the other hand the electric car is not damaged under the fire blanket.

Extinguishing blanket or fire blanket?

Colloquially, blankets that are used to contain / limit fires are normally referred to as fire blankets. Strictly speaking, however, the blankets presented here are not used to extinguish electric car fires, but to contain them or prevent them from spreading further. Accordingly, the extinguishing blankets are officially referred to as fire blankets and not as extinguishing blankets. However, for ease of understanding, both terms are used interchangeably here.

Possible initial measure even for private individuals

As described above, fire blankets are well suited to containing an e-car fire. In an early phase, it can therefore even be a possible first measure for private individuals. If there is a suspicion that the battery of a car poses a danger, a fire blanket can be pulled over the car and the fire department called, who will then take care of professional firefighting. For operators of underground garages and parking garages, such a fire blanket can also prevent damage to the building/structure if they are available on site, because the new generation of fire blankets is not only relatively light, but can also be pulled over the source of the fire by laypersons after brief instruction. It is always important to remember that you should never put yourself in unnecessary danger.

Fire extinguishers are not suitable for extinguishing electric cars

Contrary to some of the information circulating, in our opinion battery fire extinguishers are not suitable for fighting fires in electric cars. The extinguishing agent contained in the fire extinguishers has no effect due to the small volume. In addition, the battery in the electric car cannot be reached from outside. People also put themselves in great danger due to the heat and smoke development and the risk of a possible deflagration. If an electric car catches fire, you should resort to measures such as fire blankets etc. or - often the best choice for private individuals - call in professional help and leave the firefighting to the fire department, which usually has the appropriate equipment and is trained accordingly.

After extinguishing: safe removal of the electric car and cooling the battery

As a rule, extinguishing the electric car does not completely eliminate the danger, as a high-performance battery can also flare up again later. Special safety measures therefore also apply to the removal of the battery. Many fire departments or special service providers then resort to the containers described above, in which the complete electric cars are sunk. With the Car Service Set, VLITEX now has an additional option for transporting accident-damaged electric cars on classic tow trucks by wrapping them completely in a suitable fire blanket.

Long-term cooling of the Li-ion batteries during and after extinguishing

Due to the enormous thermal energy in the lithium batteries, long-term cooling of the cells is the top priority when extinguishing - of course after all safety distances and necessary precautions with regard to the electrical systems have been observed. If the electric car catches fire during charging - charging batteries is always a critical time when hazards can arise - the charging cable must of course be removed beforehand so as not to add any more electrical energy to the overall system.

Storing defective electric cars in containers filled with water

What sounds strange at first glance is often practiced: After the initial extinguishing and acute firefighting, the electric cars are stored in specially prepared containers in a water bath for several days. The thermal reaction of the battery can then be completely stopped there.

Special case: Extinguishing e-car fires in underground garages or parking garages

With the increasing spread of electric cars and plug-in hybrids, a completely new problem is emerging: if the fire department cannot drive directly up to a burning electric car, mobile extinguishing agents such as fire blankets are becoming increasingly important. In more and more parking garages or underground garages, it is therefore no longer permitted to charge or even park electric cars there.

Special extinguishing blankets for electric cars for fires in underground and multi-storey parking lots

The mobile extinguishing blankets for electric cars offer an optimal way to contain fires in underground and multi-storey parking lots, which are otherwise difficult to extinguish. Normal fire engines cannot drive up to the source of the fire in such situations, but the fire blanket can simply be transported to the electric car by two firefighters and pulled over the source of the fire. Any further spread of the fire is immediately prevented and the greatest danger is averted, and the fabric of the building is not endangered by the electric car fire.

Once the fire has been extinguished: disposal of defective Li-ion batteries

Once the fire has been extinguished, the lithium battery still needs to be disposed of properly from the vehicle. Appropriate battery transport containers are required for transportation to the disposal company. Due to the size of the batteries and their condition (the batteries are considered defective and are sent for recycling or disposal), only transport containers of packaging group 1 can be used for this purpose.

How do you discharge plug-in hybrid vehicles and hydrogen cars?

With regard to the above explanations, it can be stated that the capacity of an installed battery is directly related to the potential hazard, because the greater the energy stored in a battery, the greater the possible consequences of a thermal runway or battery fire. However, this does not mean that plug-in hybrid vehicles (PHEV) or hydrogen-powered vehicles are not affected by this problem.

Extinguishing plug-in hybrid vehicles - combination of fuel and battery fire possible

If a PHEV catches fire, there are usually two different causes of fire: On the one hand, the fuel can burn (petrol/diesel), so that classic extinguishing measures can be used. On the other hand, the battery is often also affected, so that extinguishing measures for battery fires should be used at the latest after the conventional fire has been extinguished - possibly also as a preventive measure to rule out the possibility of a battery fire from the outset. Although the Li-ion batteries of PHEVs are considerably smaller and less powerful than those of fully electric cars, this capacity is still sufficient to cause very extensive damage. From the point of view of fire departments, PHEVs are therefore actually even more problematic than purely electrically powered cars due to the combination of fuel and battery fires.

Hydrogen-powered vehicles - only a relatively small backup battery on board

In contrast to electric cars or PHEVs, hydrogen-powered vehicles only have a relatively small battery on board, as this is only used to temporarily store electrical energy. The actual energy source is hydrogen, which is converted into electricity in the fuel cell while driving and then provides propulsion in the electric motor. With this comparatively small buffer battery, the hydrogen car poses only a minor risk. The hydrogen carried in the car also poses only a minimal risk due to the high-security tanks used, because even in extreme situations, crash tests have shown that the hydrogen does not escape uncontrollably and ignite. From the fire departments' point of view, hydrogen drives are therefore the easiest cars to extinguish.

E-cars with innovative LFP batteries - less of a fire hazard

Lithium iron phosphate batteries (LFP batteries) have become increasingly popular in recent years, particularly because of their safety features. One of the main reasons why LFP batteries are considered safer, especially in terms of fire risk, is their chemical composition and thermal stability. Accordingly, they are also increasingly used in electric cars, so that the risk of fire is less high with batteries of these models.

What is the difference between LFP and lithium-ion batteries?

LFP batteries use lithium iron phosphate (LiFePO4) as the cathode material. This chemical is more thermally stable than the materials used in conventional lithium-ion batteries, such as lithium cobalt oxide (LiCoO2). This higher thermal stability means that LFP batteries are less susceptible to overheating and are less likely to suffer thermal runaway - a condition in which the battery cells generate uncontrolled heat, posing a fire risk.

Lower energy density - advantage in terms of safety, disadvantage in terms of range

LFP batteries also have a lower energy density than conventional lithium-ion batteries. Although this may initially sound like a disadvantage, especially when used in electric cars, it actually contributes to safety. The lower energy density means that less energy is released in the event of damage or malfunction, reducing the risk of rapid ignition or explosion.

Longer service life and many charging cycles

In addition, LFP batteries are characterized by a higher number of charging cycles and a longer service life, which makes them more economical in the long term. They are more environmentally friendly as they do not contain cobalt, a metal that is often mined under problematic conditions.

Increasing use in electric cars

Lithium iron phosphate batteries (LFP batteries) are also used in electric cars. In recent years, they have gained popularity in the electric vehicle industry, mainly due to their safety benefits, longevity, but also because of their lower cost. Many electric car manufacturers see the benefits of LFP batteries and are increasingly integrating them into their vehicle models, especially for models designed for efficiency and safety.