Gard says “risk of EV battery fires should not be downplayed”

Gard’s Tom Bent Opsal Nielsen Senior Claims Executive, Arendal and Are Solum Team Leader, Dry Cargo Claims, Arendal have said that Electric Vehicle battery fires can be hotter, more toxic, quicker to spread – and possibly more explosive, than other types of fires.

“Most experts agree that lithium battery fires are different and that the risks for people on board are serious. The industry needs to align and collaborate more to address the issue”, Gard said.

The writers noted that lithium batteries and the potential fire hazard they posed in electric vehicles (EVs) during transportation by sea had become a “hot topic” in the industry. Gard has now provided an overview of the main concerns and reasons behind them.

The rapid increase in demand for EVs is a game-changer for both the car industry itself and for shipping segments involved in transportation. The writers said that “as far as we know, there is no research suggesting that EVs are more likely to catch fire than other vehicles. To the contrary, some research suggests that EVs are in fact less likely to catch fire than fossil-fuelled cars. However, the significant potential for harm and damage when EVs are involved in fires on-board should be more than enough cause for concern”.

Gard also highlighted the projections for ships carrying vehicles: Currently, EVs account for a fraction more than 4% of new cars globally. This number was expected to increase significantly by 2030. “This means that no matter how infrequent EV fires are, the law of averages is against us, and the industry and regulators need to accelerate and align their efforts accordingly”, the writers said.

Gard said that in the container segment “we see a clear correlation between the rise in transported batteries and the increase in container fires”. While charcoal had long been identified as the number one cargo causing fires in the container shipping sector, lithium batteries were now becoming the predominant source.

Unlike traditional fires, EV fires are self-sustaining and do not require external oxygen to fuel them. This is because the cathode material in the battery generates its own oxygen source, enabling the fire to persist for a long time, even in environments with limited external oxygen supply.

That, in turn, calls for different fire-fighting methods. And if there is a “dual” fire (lithium and traditional”, the problem is compounded.

High temperature:

Depending on circumstances, the temperature in a lithium battery fire can be considerably higher compared to other types of fires. This may present a variety of challenges in terms of access to the fire, escape routes, firefighting, and possibly more rapid spread of the fire on a vessel. Higher temperatures can also have an impact on the different materials onboard: for instance, aluminium will melt if exposed to temperatures of 700 degrees Celsius or higher.

Vapour clouds:

Lithium battery fires emit toxic fumes, including lithium oxide, lithium hydroxide, and other hazardous chemicals. This poses a significant challenge for crew and fire-fighters. Additionally, lithium battery fires can release flammable gases like hydrogen. In confined areas like car decks, these gases can become trapped, creating an explosive environment that further endangers firefighting efforts and limits access to the scene and escape routes.

Firefighting methods:

From the container segment, Gard said that it had observed that extinguishing burning batteries in containers required a significant amount of time and a large volume of water. Generally, it appears to be the consensus that water is the best medium for extinguishing a battery fire, but getting directly to the battery and the sheer amount of water needed is a challenge on-board, as ship stability might be compromised. Furthermore, salt water had been reported to cause short circuits in EVs affected by flood water.

Some ships have CO2, some are looking at increasing CO2 supply on-board, and some may have foam systems instead of water for firefighting. These mediums have their advantages and may be effective for suppressing fires but may have limitations when it comes to extinguishing an EV fire that is self-sustaining for a long period. Foam and CO2 also comes in a limited quantity, so once used up there is no more extinguishing agent left on the ship.

Thermal runaway is a commonly-used term in the context of lithium battery fires. Essentially it refers to a situation where a battery experiences a series of reactions that cause its temperature to rapidly increase, potentially leading to a fire or explosion.

There are several factors that can trigger thermal runaway, such as overcharging or physical damage to the battery. Used rather than new EVs, damaged cars or waste batteries create an additional concern. Additionally, if the battery design is flawed and the separators that keep the positive and negative electrodes separate fail, it can start a chain reaction.

High temperatures can also initiate thermal runaway, which becomes particularly problematic if multiple electric vehicles are stored closely together, as fire can easily spread in such situations.

The writers said that “fortunately, it seems there is consensus that thermal runaway is a rare event, particularly for new EVs. However, fires onboard ships will happen, and the risk of an EV battery being involved in a fire increases with the growing number of EVs carried on car carries and Ro/Ros”.

The writers said that, based on the characteristics mentioned above, it was apparent that most firefighting methods could only suppress battery fires to some extent. Therefore it was crucial to prioritize fire suppression, boundary cooling, and fire containment as effective measures for managing a fire until professional assistance became available.

The safety of passengers and crew was of utmost importance, which meant that the unique risks posed by lithium battery fires had to be addressed thoroughly during training and when dealing with actual incidents on board. Routines for evacuation would have to be re-assessed, particularly for ferries, Gard said.

Using fixed firefighting installations was always the preferred choice in terms of ensuring crew safety. However, existing systems might have limitations when it comes to EV fires, so additional control measures might become necessary, especially when it comes to early detection.

Containing the fire before escalation should be a focus area through smarter systems and rapid response, said Gard.

“The industry, and more importantly, crew and passengers can ill afford to wait for regulation”, warned Gard.

Gard (and the insurance sector as a whole) still lacked data to make meaningful and precise insurance statistics on EV fires. “This lack of data is actually a positive sign, indicating that there are not that many incidents occurring”, claimed Gard.

Ongoing investigations into recent cases meant that conclusions have yet to be reached in many instances. “However, it is crucial to highlight that the current infrequency of cases does not translate to low risk: The number of lithium batteries present on-board any Ro/Ro or ferry voyage is steadily rising, and the potential for harm should be a concern for all of us”, the insurer concluded.