MAIB: Lithium-ion battery fire

  • Safety Flash
  • Published on 12 June 2023
  • Generated on 27 July 2026
  • IMCA SF 14/23
  • 2 minute read

Water got into lithium-ion batteries in equipment for use subsea, causing an explosion.

What happened?

Inspection of the equipment after a successful deployment identified a potential leak from one of the metal tubes. However, other work priorities meant that the technician in charge of the equipment decided to leave it in its storage area and delay the removal and further examination of the battery.  

Seven hours later, the vessel’s bridge team heard a loud bang followed by a fire detection system warning for the deepwater equipment storage area. The attending crew  members discovered a scorched and damaged metal battery tube lying on the deck.

 There were no injuries.

Seawater got into lithium-ion batteries in equipment for use subsea, causing an explosion. Inspection of the  equipment after a successful deployment identified a potential leak from one of the metal tubes. However, other  work priorities meant that the technician in charge of the equipment decided to leave it in its storage area and delay  the removal and further examination of the battery. Seven  hours later, the vessel’s bridge team heard a loud bang.
Examination of the battery tube indicated that sea water had leaked into the  battery compartment and contaminated the Li-ion battery, which caused pressurised gassesto build up and self-combust and resulted in a brief explosion. The remaining battery tubes were removed to a secure storage area for further  checks.

Examination of the battery tube indicated that sea water had leaked into the battery compartment and contaminated the Li-ion battery, which caused pressurised gases to build up and self-combust and resulted in a brief explosion.

The remaining battery tubes were removed to a secure storage area for further checks.

Actions

  • Lithium-ion batteries are widely used in IMCA members’ operations, and they are potentially very hazardous. A 1kg Li-ion battery can store the same amount of energy as a 6kg NiMH (Nickel metal hydride) or lead acid battery.

  • Lithium-ion battery failures do occur; fires in Lithium-ion batteries can be difficult to extinguish.

  • Lithium reacts intensely with water, which can corrode or damage the internal battery safety devices and cause it to overheat, ignite, rupture or leak. Some of the chemicals produced by burning Lithium-ion batteries can be very dangerous.

  • A Li-ion battery that is found to be damaged or affected by water should not be used or charged. Remove the battery to a secure place where it can be monitored and potential spontaneous combustion can occur safely. In the event of a fire, use an appropriate fire extinguisher to put it out.

Latest Safety Flashes:

MAIB: Catastrophic engine failure and subsequent fire

MAIB has published Accident Investigation Report 10/2026 into a catastrophic failure of a diesel generator engine on board the vessel Kommandor Susan.

Read more
BSEE: Compressed gas cylinder hazards

BSEE has published Safety Alert 516, relating to potential risks involving compressed gas cylinders.

Read more
MSF: dropped object inside vessel tank

MSF have published Safety Alert 26-05 relating to a tank cleaning machine coming lose and falling within a tank on a vessel.

Read more
Uncontrolled movement of cargo

During offshore cargo operations alongside a rig, a single pipe loaded on deck shifted due to vessel motion and swell conditions.

Read more
Positives – rubber seals on hatches, securing of shackle pins, fuel sample box

A Member reports a few positive findings.

Read more

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.

The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.

All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.

IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.

The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.

Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.