The risks of lithium-ion batteries and lithium-iron phosphate batteries are worrying for the shipping industry

By Lorena Petershagen, Trainee Risk Consultant, Battermann & Tillery GmbH

The advantages of lithium-ion batteries include high efficiency, high cell voltages and low self-discharge. Under normal circumstances and with proper handling, they can be classified as comparatively safe. However, mechanical damage, external thermal stress or overcharging can pose a risk. In addition, the battery itself poses risks due to the emission of toxic/flammable/explosive gases in the event of a fire and due to the fire loads of the material used.

Lithium-iron phosphate batteries (LiFePo) are often proposed as an alternative solution. Due to their lower energy density, they require more space and are usually only used in stationary systems. The lower energy density theoretically also is to help to minimise the risk of fire.

But what does this mean in concrete terms for risks regarding transported cargo and stored goods?

The main components of the two battery types are similar. In both cases, the electrolytes used consist of a highly flammable liquid, which is usually the first to burn in the case of rechargeable batteries.

However, according to the manufacturers, lithium iron phosphate batteries do not release oxygen in case of fire, making them easier to extinguish.

Even if the risk posed by rechargeable batteries in the event of a fire is to be assessed as slightly lower, it is still advisable to apply the same safety measures for their use and storage as lithium-ion batteries.

These include observing and complying with the manufacturer's instructions or product data sheets. Furthermore, both internal and external short circuits should be avoided, as should direct and long-term contact with heat. As a matter of principle, there should be spatial separation from fire loads to prevent a possible fire from spreading. In addition, using a fire alarm system can help detect a fire at an early stage of its development and thus prevent damage.

In general, it should be noted that a single safety measure alone does not provide sufficient risk reduction. A combination of different risk-minimising measures is always advantageous; after all, forewarned is forearmed.