“A fire involving an electric vehicle, for example, might require 136,000 litres of water over four hours to extinguish, compared to just 10,000-17,000 litres over 30 minutes for a traditional combustion engine vehicle,” says a recent Brookes Bell analysis. This radical disparity, based on the chemistry of lithium-ion batteries, lies at the root of the unfolding crisis in the shipping of electric cars.
When the 600-foot Morning Midas, carrying 3,000 vehicles, of which 800 were electric cars, burned and was abandoned adrift in the Pacific, maritime safety procedures and engineering practices were severely tested. Zodiac Maritime, the owner of the ship, asserted that “smoke was initially seen emanating from a deck carrying electric vehicles.” The swift spread compelled all 22 crew members to evacuate the ship, pointing to the specific dangers associated with fires on car carriers, particularly those dealing in high numbers of EVs.
The specific hazard profile of lithium-ion batteries is key to comprehending the reasons why these types of accidents are so difficult. Unlike standard car fires, a lithium-ion battery may go into “thermal runaway” a condition in which internal temperatures spike out of control, fueling the fire independently of external oxygen. As explained by Gard, “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.” This self-sustaining process ensures not only the high temperature of the fire usually well in excess of 700°C, sufficient for melting aluminum beams but also the emission of clouds of toxic and combustible gases, such as hydrogen fluoride, according to Brookes Bell. With their vapors forming explosive mixtures in the cramped conditions of a car deck, it becomes difficult to fight fires and also evacuate people.
While statistically there is still less chance of an EV catching fire compared to internal combustion engine (ICE) vehicles “in general, there are fewer fires from EVs compared with fires from conventional vehicles when driven over the same distance,” according to IUMI Secretary General Lars Lange the impact when they do happen is out of proportion. The acceleration of fire spread on a car carrier is facilitated by the tightly packed positioning of the vehicles and the very high flammability of interior plastic and body components. As per the International Union of Marine Insurance, “once established, vehicle fires are largely (approx. 80%) fueled by the car body and interior parts rather than the propulsion system.”
The salvage and firefighting efforts for ships such as the Morning Midas are informed by hard-won experience from recent tragedies. In the sinking of the Felicity Ace in 2022, after a nearly weeklong fire, salvage officials said that “the presence of a large number of lithium-ion batteries likely caused the fire to spread and complicated efforts to extinguish it.” The problem is exacerbated by the narrow capabilities of shipboard fire suppression systems. As set out in Lloyd’s List, ICE and EV fires can achieve peak heat release within 6–10 minutes of initiation but, if left unchecked within 10–15 minutes, the deployment of fixed firefighting systems is necessary. However, even sophisticated CO2 or foam systems can quickly be consumed, leaving responding crews with limited choices as fires keep restarting due to residual battery heat.
Early detection is increasingly being accepted as a key to successful fire response. Consilium Safety Group’s Isak Nordberg discusses, “With these extra minutes, you can, for example, cover a vehicle with a special fire blanket. This action can prevent the fire from spreading to other vehicles.” Their Early Detection software, which employs machine learning to optimize heat detector sensitivity, provides up to four minutes of extra warning time that can prove critical in suppressing a fire before it gets out of control.
The regulatory environment has not, however, evolved with technological and market developments. The International Maritime Dangerous Goods (IMDG) Code presently categorizes lithium-ion batteries as “miscellaneous” within Class 9, a designation not entirely in keeping with their risk profile. More seriously, as Brookes Bell explains, “electric vehicles are not required to be declared as dangerous goods when transported on car carriers, leaving crews unaware of how many EVs are onboard or their specific locations.” There are also no obligatory limits on EV battery state of charge at sea, even though there is a suggestion that reduced charge amounts can slow thermal runaway. Certain operators, like Wallenius Wilhelmsen, have voluntarily restricted onboard charging of batteries to 30% and required explicit marking of EVs on stowage plans.
The International Maritime Organization (IMO) has started closing these loopholes. In March 2024, its Sub-Committee on Ship Systems and Equipment initiated an action plan to “enhance fire safety measures” with enhanced detection, prevention, and extinguishing systems. In the meantime, temporary guidelines like MSC.1/1615 and recommendations by the European Maritime Safety Agency (EMSA) are being embraced by forward-thinking operators, who today use thermal imaging, AI-based monitoring, and specialized crew training to mitigate EV fire hazards.
The financial and environmental risks are great. Hazardous material fires such as from lithium-ion batteries can lead to the emission of toxic materials into the ocean, as in the Grande America spill that resulted in extensive pollution. For shipowners and insurers, financial losses from cargo damage, salvage efforts, and claims of liability can be hundreds of millions of dollars. Allianz’s Rahul Khanna highlighted the magnitude of the threat: The latest car carriers are able to transport as many as 10,000 electric vehicles… that’s a lot of value, and risk to the environment and to the safety of seafarers.
Salvage and investigative practices are adapting to these events. Shipowners no longer hesitate to enlist private salvors, insurers, and flag state authorities in months-long investigations, and insurers such as UK P&I have created specialized risk management departments to examine new dangers. Industry associations like the Vehicle Carrier Safety Forum and others are releasing best-practice guidance, focusing on early suppression, fixed fire-extinguishing systems, and current stowage data including engine types of the vehicles and battery locations.
As the number of EVs transported by ship keeps increasing, the maritime industry is facing a steep learning curve. Active defense via sophisticated detection, expert training, and stringent regulatory schemes is emerging as the new norm for dealing with the intricacies of lithium-ion battery fire risk at sea.
