Hybrid Battery Systems: Is The Future Without Risk?
Hybrid propulsion typically combines lithium‑ion battery banks with traditional propulsion often diesel or LNG engines. These systems are rapidly gaining traction across the maritime industry. Yet the shift brings both opportunity and risk. Here’s what operators need to know.
The Upside
Hybrid and battery systems can reduce carbon emissions, lower NOx and SOx output, and offer operational cost savings. This is particularly true for vessels operating in emission control areas or making frequent port calls.
Retrofitting existing vessels is becoming more economically viable as battery prices fall, making hybrid systems increasingly attractive alongside cleaner propulsion technologies.
The Risks
Lithium-ion batteries pose a major safety risk if not properly managed. One of the main issues we have seen is thermal runaway; an uncontrolled increase in battery temperature. This leads to high-intensity fires that are resistant to traditional suppression. These fires also emit toxic gases which can be dangerous for all on board.
A recent example of this is Morning Midas who caught fire mid-pacific while carrying 800 EVs. The crew had to evacuate after the CO₂ fire suppression system was exhausted and the fire reignited.
Another issue that the industry is are facing is the standards for marine battery installations remain non-uniform and often voluntary. Without tighter regulations and guidance, operators face legal, safety, and reputational risks.
Lastly, the design and operational complexity of such systems requires careful monitoring and management. Inconsistencies at the cell level, whether due to manufacturing deviations or usage patterns, can increase risk.
The Verdict
Hybrid battery systems offer a clear route to cleaner ship operations and future regulatory compliance. Yet those advantages come with significant new safety responsibilities. Fire risk, regulatory uncertainty, and technical complexity demand that adopters proceed with caution and robust risk management strategies.
So, what can operators do to stay ahead?
R&Co recommends deploying early-warning detection systems, advanced cooling, and compartmentalisation to mitigate fire risk. We also advise that you implement battery management systems (BMS) and risk monitoring tools to detect module imbalance or ageing.
Ensure your crew training and emergency procedure updates are tailored specifically to battery fire scenarios. We’d highly recommend running drills aligned with EV fire realities.
If you're considering hybrid or battery-electric propulsion, speak to our expert team about how an audit can help assess risk and operational readiness. We’re here to ensure your next move is both forward-thinking and fully informed.