Lithium-ion batteries – should we be concerned?

Six stacks of battery modules in one of the battery rooms. Illustration: The battery contractor
Six stacks of battery modules in one of the battery rooms. Illustration: The battery contractor

An opinion article by Mike Schwarz, IIMS Chief Executive Officer.

I have written this short article following the publication of a report into a lithium-ion battery-related fire onboard the ‘MS Brim’ which generated the investigation by the Norwegian Safety Investigation Authority. The vessel in question is the ‘MS Brim’, a 2019-built all-electric excursion catamaran offering excursion tours in the Norwegian fjords. Although not a technical man, I am troubled by some of the report findings, and forgive me as I have cherry-picked the bits that concern me most from a lengthy report.

So, I pen this article in my simplistic way as a) just a concerned and interested member of the general public and b) in my role as Chief Executive Officer of the International Institute of Marine Surveying on behalf of the surveying community.

Lithium-ion batteries are not brand new, but the technology is becoming far more widely used in vessels as the world looks to decarbonize and cut emissions. The purpose of this article is not to be negative and closed to new technology, but rather to express my concerns based on what I have read with regards to this incident in particular and the safety culture around this means of propulsion. At 81 pages, the report is detailed, but I would encourage you to download it at

Let me take some words directly from the report itself:
‘Immediately before the fire broke out, the battery system was disconnected as a result of a ground fault, which was indicated on the panel on the bridge. Ground faults had been a recurring problem since the vessel was new. The crew, therefore, perceived the alarm as ‘one of many’.

In the interests of public and crew safety, I ask why this was thought to be acceptable and why no-one reported or do anything about a recurring problem?

Back to the report:
‘There was no camera surveillance of the battery room. The presence of a camera might have helped the crew to dispel the incorrect perception that it was the engine room that was on fire. The DNV’s updated classification rules from 2021 recommend camera surveillance of battery rooms to improve the crew’s situational awareness, in addition to gas monitoring for early detection of gases before they develop into smoke’.

I leave you to draw your own conclusions on this paragraph.

And here is another statement from the report that caused me to raise my eyebrows:
‘The investigation has also identified several areas where the risks associated with the use of lithium-ion batteries were not sufficiently identified or addressed in the design. At present, DNV’s classification rules for battery safety do not sufficiently address the risks associated with the use of lithium-ion batteries on board vessels’.

Clearly there is the suggestion that the vessel design is at fault. Will appropriate modifications be made to ensure this issue is addressed? As a potential traveller to the Norwegian fjords sometime soon, I do hope so! Mention in the report that a classification society’s rules have yet to catch up with the technology does nothing to boost my waning confidence either. As so often seems to be the case in the marine world, it appears that technology is running faster than the rule makers or maritime regulators can keep up with. I wonder how differently things might work in the aircraft business. It seems incongruous that it would be acceptable for a few of the new breed of lithium-ion powered aircraft that will surely be in the skies soon should catch fire and crash. So, what is the aircraft industry doing differently and what could the maritime sector learn?

And now, to conclude, here are the safety recommendations extracted from the report:
The Norwegian Safety Investigation Authority recommends …
– that the Norwegian Maritime Authority issues requirements for appropriate test methods that reflect the risks associated with the design of different battery types to be chosen for conducting propagation tests.
– that the Norwegian Maritime Authority ensures that battery safety regulations be developed so that ventilation arrangements do not contribute to batteries and high-voltage components being exposed to humid sea air or seawater.
– that the Norwegian Maritime Authority introduces additional measures to verify that installations are smokeproof and ensure fire integrity.
– that the Norwegian Maritime Authority issues requirements for risk assessments relating to the use of lithium-ion batteries, and that they should contain all relevant risks identified by different disciplines, the sum of which represents the vessel’s fire risk.
– that the Norwegian Maritime Authority, as the administrative authority, cooperates with the Directorate for Civil Protection on stipulating a requirement that all Norwegian vessels, regardless of classification, must be built to a defined standard that ensures battery safety.
– that the Norwegian Maritime Authority introduces compensatory measures to address the safety of passengers and crew in the event of a lithium-ion battery fire.
– that the Directorate for Civil Protection strengthens the knowledge and expertise of the parties involved in the first-line response to accidents involving a fire on board a vessel carrying lithium-ion batteries.

Gosh, that’s a lot of safety recommendations, but read them carefully and re-read them to understand exactly what is being recommended. There is a huge onus being placed on the Norwegian Maritime Authority to react and presumably, this same pressure applies to other maritime regulators around the world.

So, there you have it. All I want to know is that when I get onboard such a vessel as a paying passenger, I am reasonably safe! And in my professional role, I want marine surveyors to be aware of some of the new challenges that await them today and in the near future surrounding lithium-ion battery technology and vessel design. I would like to encourage a debate around this topic, but if nothing else, I wanted to alert people to the situation.

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