As a key component of electric vehicles (EVs) or electronic devices, the transport of highly inflammable lithium-ion (Li-ion) batteries is increasingly affecting shipping safety, as demonstrated by a number of fires on vessels such as roll-on roll-off (ro-ro) car carriers and container ships. Given the many difficulties involved with suppressing battery fires, particularly at sea, focusing on loss-prevention measures is crucial, whether batteries are transported within EVs or as standalone cargo, according to a new report from marine insurer Allianz Global Corporate & Specialty (AGCS) .
Hazards and causes
The report 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; overcharging 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.
See also: Will Electric Vehicles Be Safer?
Loss-prevention measures for EVs on car carriers and in containers
Recommendations to mitigate the fire risk that can result from Li-ion batteries during the transportation of EVs on car carriers and within freight containers include ensuring that staff are trained to follow correct packing and handling procedures and that seafarers have had Li-ion battery firefighting training; checking the battery’s state of charge (SOC) is at the optimal level for transportation, where possible; ensuring that EVs with low ground clearance are labeled, as they can present loading/discharging challenges; and checking all EVs are properly secured to prevent any shifting during transportation. In transit, anything that can aid early detection is critical, including watchkeeping/fire rounds and using thermal scanners, gas detectors, heat/smoke detectors and CCTV cameras.
Ensuring safe storage of Li-ion batteries in warehouses is particularly important, as large-format batteries, such as those used in EVs, ignite more quickly in a warehouse fire than do smaller batteries used in smartphones and laptops. Recommendations include training staff in appropriate packing and handling procedures; establishing an emergency response plan to tackle damaged/overheating batteries and a hazard control plan to manage receiving, storage, dispatch and supervision of packaged Li-ion batteries; preventing the exposure of batteries to high temperatures and ensuring separation from other combustible materials; as well as prompt removal of damaged or defective Li-ion batteries.
If the maritime industry is to improve 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. Regulations and guidance are specific in addressing these batteries to help prevent most incidents, but 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.
Other relevant findings from the report include:
- AGCS analysis of over 240,000 marine insurance industry claims over the past five years (with a value of €9.2 billion), shows that fire/explosion (from all causes) is the most expensive cause of loss, accounting for 18% of the value of all claims.
- The number of fires (from all causes) on board large vessels has increased significantly in recent years. Across all vessel types, fire/explosion was the second top cause of the 54 total losses reported in 2021 (eight), second only to foundered (12). Over the past decade fire/explosion ranks as the third top cause of loss overall, accounting for 120 out of 892 reported total losses, behind foundered (465) and wrecked/stranded (164).
- Ro-ro and car carriers can be more exposed to fire and stability issues than other vessels. To facilitate carriage of automobiles, the internal spaces are not divided into separate sections as in other cargo ships. The lack of internal bulkheads can hurt 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.