By Tim Houchin

The marine industry has long sought more sustainable and efficient energy storage systems (ESS), especially with the transition to greener technologies. Traditionally, lithium-ion (Li-ion) batteries have dominated energy storage markets due to their high energy density and relatively light weight. However, in recent years, carbon-based batteries have emerged as a strong alternative, especially in marine applications, ranging from sensors to underwater drones to vessels small and large (https://digitalbattery.co.uk).

Li-ion batteries come with safety concerns, such as thermal runaway, which can lead to fires or explosions, particularly when exposed to physical damage, temperature fluctuations, or water. This poses a significant risk in marine settings where exposure to extreme weather, saltwater and physical stress is common.

Carbon-based batteries, on the other hand, are more stable and safe. They are not prone to overheating and, thus, do not pose a fire hazard and are more resilient to temperature changes.

Saltwater and humidity create corrosive conditions in marine environments. Li-ion batteries are sensitive to moisture and need careful sealing and insulation to prevent degradation, which can increase maintenance costs and complexity.

Carbon-based batteries, particularly those made with advanced carbon materials, such as graphene or carbon nanotubes, offer superior resistance to corrosion. Their inherent durability makes them better suited to handle the challenging conditions at sea, reducing the frequency of maintenance and extending battery life.

Carbon-based batteries excel in energy efficiency and charging speed compared to Li-ion. Many carbon batteries, especially supercapacitors and hybrid designs, have faster charge and discharge rates than Li-ion batteries. This is particularly useful in marine applications where quick energy recovery is necessary, such as in electric boats or submarines. Fast charging times can also reduce downtime during port stays or in emergencies. The high cycle life of carbon-based batteries (tens of thousands of cycles in some cases) ensures they remain efficient and operational over long periods. They can handle frequent charge-discharge cycles without significant degradation.

As the marine industry moves toward sustainability, reducing its environmental footprint is becoming increasingly important. Li-ion batteries rely on lithium, cobalt and nickel, which come from resource-intensive mining processes. Additionally, the disposal of lithium-ion batteries can be problematic and expensive due to the presence of hazardous materials.

Carbon-based batteries are more eco-friendly. Carbon is abundant and can be sourced sustainably. In addition, carbon-based batteries often do not contain toxic materials, making end-of-life management easier.

Carbon-based batteries are more easily scalable without compromising safety or efficiency. They are also modular, so they can be tailored to the specific energy needs of an application. Carbon-based batteries have 98.6 percent energy availability at low discharge rates, resulting in high reliability.

While Li-ion batteries have dominated the market, carbon-based batteries are emerging as a better option for marine environments. Their safety, durability, energy efficiency and environmental benefits make them well-suited to the challenges of the sea. As the marine industry continues to prioritize sustainability and cost-efficiency, carbon-based batteries are positioned to play a crucial role in powering the future of marine energy storage systems.

Tim Houchin is the co-founder and CCO of Digital Battery Ltd.