Lithium-ion batteries: fire risks and loss prevention measures in shipping

Risk bulletin | August 2022

Although shipping losses have more than halved over the past decade [1], fires on board vessels remain among the biggest safety issues for the maritime industry. AGCS analysis of over 240,000 marine insurance industry claims between January 1, 2017, and December 31, 2021, worth approximately €9.2bn in value, shows that these are the most expensive cause of loss, accounting for 18% of the value of all claims.

As recent events have demonstrated, roll-on roll-off (ro-ro) car carriers [2], the largest of which can hold as many as 8,000 vehicles, can be susceptible to fire risks (see box), while there have also been a number of blazes on container ships [3]. 

In March 2022, the fire and subsequent sinking of the ro-ro carrier Felicity Ace [4] with the loss of some 4,000 vehicles, put the risks associated with transporting electric vehicles (EVs), and the lithium-ion (Li-ion) batteries that help power them, firmly in the spotlight. The exact cause of the fire may never be known, but it is thought the presence of Li-ion batteries on board aggravated the fire conditions. Given the growing popularity of EVs means many more vehicles with Li-ion batteries will be transported by sea in future – together with the fact that this was not an isolated incident (see box) – it is crucial that the maritime industry focuses on loss prevention best practice.

“AGCS has long warned [5] about the potential dangers that lithium-ion batteries can pose for the shipping and wider logistics industries, whether they are being transported inside electric vehicles or as standalone cargo, if they are not handled, stored or transported correctly, with fire being a significant hazard,” explains Captain Rahul Khanna, Global Head of Marine Risk Consulting, AGCS

“Batteries are not only a potential cause of fire if damaged, overcharged or subjected to high temperatures, they can also aggravate other causes of fire at sea and are difficult to extinguish as they have the potential to reignite days or even weeks later,” says Khanna. “Safe carriage has become an emerging risk concern for the shipping community, raising questions about the adequacy of fire detection and firefighting capabilities on board vessels, cargo loading procedures and even whether changes in vessel design may be necessary, given specialist equipment is required to extinguish any blazes and salvage operations at sea can be challenging.”

A new risk bulletin from AGCS: Lithium-ion batteries: Fire risks and loss prevention measures in shipping highlights four main hazards: fire (Li-ion batteries contain electrolyte, an ignitable liquid); explosion (resulting from the release of ignitable vapor/gases in a confined space); thermal runaway (a rapid self-heating fire that can cause an explosion); and the toxic gases that these hazards can produce. The most common causes of these hazards are substandard manufacturing of battery cells/devices; over-charging of the battery cells; over-temperature by short circuiting, and damaged battery cells or devices, which, among other causes, can result from poor packing and handling or cargo shift in rough seas if not adequately secured.

In most shipboard incidents a thermal runaway event can be a significant possibility unless immediate action is taken by the crew, such as suppressing a fire with copious amounts of water over a long period of time. However, this can be extremely challenging due to factors such as early detection being difficult, a shortage of crew members, and a lack of adequate firefighting capabilities on board.

Therefore, the primary focus must be on loss prevention and in the bulletin Allianz marine risk consultants highlight a number of risk mitigation measures for stakeholders through the supply chain to consider, including recommendations for shipping Li-ion batteries installed in EVs and as standalone cargo, as well as steps that can be taken to ensure safe storage in warehouses.

While EVs are inherently safe, they do represent a significant difference in risk profile for shippers when compared with traditional vehicles and transporting them may represent an enhanced risk for the maritime industry, at least in the near-term.  To mitigate the fire risks that can potentially result from Li-ion batteries during the transportation of EVs on car carriers and within freight containers, the bulletin highlights a number of recommendations including:

  • Ensuring staff are trained to follow correct packing and handling procedures and that seafarers have had Li-ion battery firefighting training
  • Ensure the battery’s state of charge (SOC) is at the optimal level for transportation. This ranges from 30% to 50%, depending on the manufacturer’s recommendations and the length of the voyage
  • Review the safety data information describing the process, and preventive actions to be taken in case of an accident
  • Check that all EVs display identification on windshields detailing the battery type 
  • Ensure that all EVs with low ground clearance are labelled as this can present loading/ discharging challenges
  • Check whether the EVs have an undamaged battery system and ensure there is no charging during the voyage
  • Check that all EVs are properly secured to prevent any shifting during transportation  
  • Early detection systems are critical, including watchkeeping/fire rounds, thermal scanners, gas detectors, heat and smoke detectors, and CCTV cameras

The bulletin also highlights a number of loss prevention measures that can help ensure safe storage of Li-ion batteries in warehouses, noting that large-format batteries, such as those used in EVs, ignite more quickly in a warehouse fire than small format batteries used in smartphones, laptops and power tools. Recommendations include:

  • Training staff in appropriate packing and handling procedures
  • A pre-defined Emergency Response Plan should be established to tackle damaged or overheating Li-ion batteries. Key employees should be trained in this before batteries are permitted on site
  • A pre-defined Hazard Control Plan to manage receiving, storage, dispatch and supervision of packaged Li-ion batteries should also be developed
  • Pre-emergency planning with the local fire department and on-site fire brigade, if available, is important, given the specific procedures that must be followed to eliminate the hazard
  • Follow the manufacturer’s guidance for use and storage
  • Protect battery poles from short circuit
  • Do not expose to long-term high temperatures or heat sources (including direct sunlight)
  • Ensure structural or spatial separation (min. 10 ft or 3 m) from other combustible materials if there is no automatic extinguishing equipment present 
  • Floor stacking of Li-ion batteries should be strictly controlled in designated areas with limited stack heights, footprints and separation distances
  • Rack storage of Li-ion batteries should not be permitted unless the building and the racks are fully protected with a sprinkler system, with solid metal horizontal and vertical barriers between each storage bay
  • Ensure prompt removal of damaged or defective Li-ion batteries
  • Installation of a gas detection method targeting CO2 concentration and shock/impact and vibration sensors on large-format batteries should also be considered
“If the maritime industry is to improve its incident record related to the transportation of lithium-ion batteries all parties involved in the supply chain must understand the hazards involved, the most common causes and the problems associated with transporting in commerce,” says Captain Randall Lund, Senior Marine Risk Consultant at AGCS, author of the report together with fellow AGCS marine risk consultants Miguel Herrera and Justin Kersey. “Regulations are specific in addressing these batteries to help prevent most incidents, but these can only be effective if they are communicated and enforced. Only through a concerted effort by stakeholders in the supply chain can we hope to reduce the rate of incidents.”
  • In March 2022, the US Coast Guard [6] issued a safety alert about the risk posed by Li-ion batteries following two separate container fires caused by mis-declared cargo. The first saw a shipping container waiting to be loaded onto a ship bound for China catch fire. In August 2021, a container full of discarded lithium batteries caught fire while being transported by road to the Port of Virginia, where it was due to be loaded onto a container ship. The cargo was mis-declared as ‘computer parts’
  • In June 2020 a fire on the car carrier Höegh Xiamen [7] in Florida lasted for eight days before it was put out – a failure to properly disconnect and secure vehicle batteries was the cause
  • In January 2020, the cause of the fire in one of the cargo holds of the container ship Cosco Pacific [8] was the combustion of a Li-ion battery cargo which was not properly declared

Ro-ro and car carrier vessels can be more exposed to fire and stability issues than other vessels and require additional emphasis on risk management. To facilitate carriage of automobiles the internal spaces are not divided into separate sections like other cargo ships. The lack of internal bulkheads can have an adverse impact on fire safety and a small fire on one vehicle or battery can grow out of control very quickly. Vehicles are not easily accessible once loading has been completed. The large volume of air inside the open cargo decks provides a ready supply of oxygen in case of fire. 

A number of accident investigations have revealed that pre-sail away stability checks were either not carried out as required or were based on inaccurate cargo information. In many cases cargo was not fully secured prior to sailing and inadequate lashing of cargo such as EVs could lead to a thermal runaway and ensuing fire. For cargo ro-ro and vehicle carriers, improved cargo securing and weather routing should be considered.

The number of fires on board large vessels has increased significantly in recent years. Across all vessel types and causes, fire/explosion was the second top cause of the 54 total losses reported in 2021 [9] accounting for eight, second only to foundered (12). Over the past decade (2012 to 2021) fire ranks as the third top cause of loss overall, accounting for 120 out of a reported 892 total losses, behind foundered (465) and wrecked/stranded (164). In 2021 fire was the third top cause of shipping incidents overall around the globe – behind machinery damage (1,311) and collision (222). There have been 41 total losses involving ro-ros over the past decade with fires causing six losses.

[1] AGCS Safety & Shipping Review 2022, 54 total losses (over 100 GT) at end of 2021 compared to 127 at the end of 2012.
[2] AGCS Safety & Shipping Review 2022;  Loss drivers in the shipping industry: larger vessels, May 2022
[3] AGCS Safety & Shipping Review 2022;  Loss drivers in the shipping industry: larger vessels, May 2022
[4] AGCS Safety & Shipping Review 2022;  Loss drivers in the shipping industry: larger vessels, May 2022
[5] AGCS Risk Bulletin: Lithium-Ion Batteries, 2017
[6] US Coast Guard Marine Safety Alert: Lithium Battery Fire, March 10, 2022
[7] National Transportation Safety Board; Failure to Properly Disconnect and Secure Vehicle Batteries Led to Fire Aboard Vehicle Carrier Höegh Xiamen, December 16, 2022
[8] Port Technology: COSCO says lithium battery started vessel fire, January 8, 2020
[9] AGCS Safety & Shipping Review 2022;  Loss drivers in the shipping industry: larger vessels, May 2022

Pictures: Adobe Stock

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