Are lithium-ion batteries to blame for recent boat blazes?

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Are lithium-ion batteries to blame for recent boat blazes?

12 January 2023 • Written by Sam Fortescue

A spate of boat blazes have led to warnings of keeping lithium-ion batteries on board. But are they to blame? Sam Fortescue investigates...

Luckily the crew of the yacht Blue Vision were still up at 1.30am, otherwise there would have been no one to notice the fire taking hold. Speaking to investigators after the inferno in September 2021, they described “intermittent bright flashes” on the aft deck of the 35 metre Tansu yacht Siempre, moored stern-to a few places down the quay in the Port of Olbia.

What happened next unfolded quickly. “They stated that the fire soon spread across the aft deck and that they observed that within seconds, the flames reached a height of between two and 2.5 metres,” according to the report published afterwards by Malta’s Marine Safety Investigation Unit. “In the meantime, the crew of Siempre, who were asleep in the cabins, were alerted by the yacht’s fire alarm. The chief engineer ran up the interior stairway to investigate and, on reaching the saloon on the main deck, he observed a large fire on the aft deck. He ran back to the crew’s accommodation and instructed the rest of the crew members to vacate... through the escape hatches on the yacht’s bow.”

Emergency services work to put out the flames on board Siempre. The accident report suggested that the cause of the blaze may have been a faulty water toy battery
Credit: Vigili del Fuoco

The chief engineer tried to fight the blaze by attaching a hose to the fire pump, and a neighbouring yacht trained its fire hose on the blaze as well. The fire brigade arrived 20 minutes later, by which time the flames had spread to the bridge deck. “Moments later, all four crew members of Siempre jumped into the water from the bow,” continues the report. By 2.30am, the yacht was a ball of livid flame. She listed over, then partially submerged the next morning and was declared a total loss.

Astonishingly, investigators later reported that they thought the source of the devastating fire was likely to have been a faulty lithium-ion battery for the owner’s water scooter, or a fault in its power socket. Crew were aware of a problem with both items, having previously repaired scorching inside the socket. And they were awaiting instructions on disposing of the faulty battery, keeping it in a locker for safety.

Dramatic though this story is, it is far from an isolated example as yacht owners tool up with more and more electric toys and tenders. Precise figures are almost impossible to come by, but analysis from insurer Allianz Global Corporate & Specialty found that 18 per cent of marine claims from 2017 to 2021 came down to fire, resulting in losses of €1.65 billion (£1.42bn). These include the loss of the 200-metre-long car carrier Felicity Ace in March 2022, with hundreds of electric vehicles aboard. It is not known whether the fire started with one of these cars, but it is thought that their lithium batteries quickly aggravated the blaze.

The remains of a 26 metre Princess were raised in Torquay marina following a blaze in May 2022.
Credit: Ian Williams

Fingering lithium-ion as the culprit is a tricky business, according to Captain Herb Magney, consultant with First Look, Inc. “There are cases where it has been proven that the lithium batteries have been the culprit of recent fires,” he tells me. “They are highly suspect in the majority of the rest. The biggest obstacle to proving they are the culprit is that all of the evidence is usually at the bottom of the sea or a marina or just destroyed in the fire.”

Magney believes this is the tip of the iceberg. “What is missing from the data banks right now, is the hundreds of near-misses,” he exclaims. “I have seen several, been involved in a few and know first-hand from watching blazing batteries getting thrown overboard about many more.”

In many cases, the cause of the fire never reaches the public domain. Or the report by the flag state takes years to surface. Director Steve Monk of Da Gama Maritime doesn’t mince his words. “I’m bored of beating about the bush.  Just a shame it’ll likely take a death to happen to bring about a change in attitude,” he says with more than an edge of exasperation. “Battles against confidentiality agreements, release of accident reports and indeed even the notification of accidents regardless of their cause are still areas where we need to get more clarity. Try kicking those doors open and we may get somewhere, rather than just setting fire to yachts or harming crew trying to put out preventable fires with equipment they’re not safe to operate.”


What goes wrong with lithium-ion batteries? 

Lithium is a highly reactive alkaline metal. This makes it ideal for storing large amounts of energy in battery form, but also makes it potentially explosive when something goes wrong. The key is in the construction of the cells which make up the battery. When in use, electrons flow between the cathode and the anode through a perforated separator. If this membrane breaks down, either through poor manufacture, old age or mishandling, a short circuit can occur. Then thecell quickly heats up, the electrolyte expands and a toxic, flammable gas is vented, sometimes explosively. In bigger batteries with multiple cells, the heat starts to damage neighbouring cells, which then also malfunction. This process is called thermal runaway and, once triggered, it is very hard to stop. When the cell is breached, highly reactive lithium simply adds fuel to the fire. 

Nonetheless, there are those who are keeping unofficial tabs on the stories of yacht fires that do make it into the press. Michael Pavluk of yacht security specialist Frankentek says: “Of the more than 20 yachts that have caught fire since 2018,  I have not seen in the reports that a death has occurred, which is great news. But collectively,  the marine industry from underwriters, class, technology and IMO need to address this issue now before someone becomes a statistic.”

Faced with what they see as serious industry inaction, Magney, Pavluk and Monk have assembled a working group of concerned insiders to chisel out a response to the threat of lithium battery fires on yachts. Collectively, they represent interests from insurance, yacht management, manufacturers and yacht captains. And when it comes to fire risk, not all lithium batteries are born equal, according to Magney. “The proverbial problem children in this story are the high-energy LiPo variant (lithium-ion-polymer) portable batteries,” he says. “The ones that consumers can take out of the driven equipment and handle, charge, then reinstall for use. I am not so concerned about engineered hard installations.”

And there are good reasons for that, because the large-scale energy storage banks that feature in big hybrid yachts will be professionally installed with class approval. That means that the space will have been designed with suitable ventilation, detection and suppressant systems in place, while batteries will also be physically separated into different compartments. As Oceanco points out, the build quality will generally be higher than that in the commercial sector, with fire suppressant systems both within the batteries and externally in the battery room.

Steve Monk of Da Gama Maritime trains crew on board their yachts
Credit: Ted Fitzgerald of Clear Blue Sky

Even for refits and new builds below 500 gross tonnes that don’t have to comply with SOLAS, there are relatively simple solutions available to make the fixed battery banks as safe as possible. “Active systems are available that draw smoke, carbon monoxide, hydrogen and combustible gases to an analyser, providing a few minutes to 30 minutes of very early warning,” explains Pavluk.

It is not expensive in the context of a superyacht budget – and certainly not compared to the total loss of the boat. An entry-level Frankentek system with four Li-ion Tamer sensors from Nexceris and a reference sensor capable of monitoring four cubic metres costs around €15,000.

British company Thermarestor is just starting to market a small, inexpensive device that can spot the tell-tale build-up of heat within a circuit, triggering an alarm to alert crew. It activates at around 80°C, and you need one at every connection point to monitor a circuit – but costs are as low as £8 per sensor. “We firmly believe that the device can help manage the harmful effects of a lithium-ion battery fire – and if not actually prevent it, provide warning that something is going wrong,” says Matthew McKaig of Thermarestor.

Portable batteries are another matter. Not only do they absorb a fair amount of abuse in the toy itself – just think of a beginner on an e-foil – but they are also regularly handled and charged by the user. “Most problems come from the mishandling of good products,” says Magney. “This same principle applies to everything. I can hurt you with a burrito if I use it the wrong way or put it in the wrong place.”

Credit: Stevie-Iona Vaughan/Facebook

It is a view broadly shared by Ian Hoy of superyacht insurer Beazley. “Toys are perhaps the most challenging category,” he says. “In the case of Siempre, there were two electric surfboards, an electric hydrofoil surfboard and two electric underwater scooters on board at the time of the fire. Having a personal watercraft or toy is not a bad thing – but key to their enjoyment is making sure that they are safe and properly looked after.”

E-foil manufacturer Fliteboard insists that not all lithium batteries should be tarred with the same brush, as it has sold 10,000 units with “a perfect safety record”. Not only has Fliteboard tested its batteries by puncturing them with nails and repeatedly dropping them, but the cells are also engineered to a higher quality from the start. “We use premium 21700 cells, and a specific brand and model of cell that offers the lowest impedance on the market and the highest current rating,” explains founder David Trewern. “This means our cells stay cooler than other cells, and are used well below their maximum operating thresholds for discharge and charging.”

Owners will rarely know exactly what toys they want when they start a build project, and will want the flexibility to add new ones later, so Lloyd’s Register has developed detailed guidance which applies to any yacht. “The type and details of lithium gadgets are unknown at the design stage of the yacht. However, shipyards need to provide arrangements and make provisions for safe charging and storage of such electrical supplies on board,” says global yacht segment director Engel-Jan de Boer. Lloyd’s’ approach is to design battery storage areas with a maximum safe power capacity, which should not be exceeded. “Most importantly, charging and storage of lithium gadgets should only be carried out in dedicated lockers, cabinets or spaces being compliant with the safeguards.”

Fliteboard’s Flitecell has a perfect safety record
Credit: Fliteboard

This stance works as long as class is involved. Flag states such as the Red Ensign Group are also working on more detailed guidelines for yachts, but smaller boats will slip through this net. So insurer Beazley has taken the unusual step of setting out battery handling requirements as a condition of cover, mandating that batteries should never be charged unattended, for instance. Charging should take place on deck,  not in an enclosed space, always using the manufacturer’s charging device on a heat-proof mat. When not in use, lithium batteries should be stored in a fire-proof box.

Five years ago, a narrowly avoided lithium battery fire on a yacht covered by Beazley persuaded the insurer to lay down the law. “Since then, we have asked for details of any lithium-powered toys to be notified to us so that we can make sure the appropriate risk mitigating actions are included within our quote to help manage the threat,” says Hoy. “It is possible that in the not-too-distant future, there might be specific surveys to look at how lithium-powered toys are being stored and charged on board.”

A battery charging box is the key item of kit here. There are many brands on the market offering blast protection, extreme heat resistance and charging capabilities for multiple batteries. Some also contain fire-suppression equipment. “You can dictate what size you want and can put all your lithium batteries in there to charge – it goes some way towards mitigating risk from a thermal overload and spread,” says experienced captain Malcolm Jacotine.

Beazley’s rules on safer lithium battery storage

  • No charging while the yacht is unattended, or between sunset and sunrise
  • Only charge on deck
  • Only use the original manufacturer’s supplied charger
  • Charge batteries on a heatproof mat
  • Follow the manufacturer’s recommendations
  • Operational fire extinguishers suitable for lithium-ion batteries to be on board and accessible by crew members in the event of a fire
  • When batteries are not being charged or in use, store them in a fireproof box

The space must be well-ventilated to get rid of toxic gases, and covered by lithium fire extinguishers, such as those with aqueous vermiculite dispersion technology. Detection kit should be based on the same active gas analysis that is used for fixed battery installations. It is not enough to monitor for heat or abnormal electrical performance, because these signs of a malfunctioning lithium cell come far too late, when thermal runaway may already have set in.

Another experienced captain, Scott Gaffga, says that he has drawn up a battery checklist and put it under the bosun’s command. “This makes it much safer, as one person charges and inspects the batteries,” he explains. Every battery is inspected before charging, and then stored in a fireproof box. The management company behind Siempre, Private Yacht Group, also now recommends that its owners “consider” fitting a storage box “as soon as possible”. It has also updated guidance to say that faulty batteries must be removed from the boat as a priority.

Steve Monk and Mike Pavluk are keen to have the final word in this debate. As much as they are focused on developing useful solutions to protect against lithium-ion fires on yachts, they are furious that management companies and owners are not doing more themselves. “One big frustration is that many owners live in the misconception that crew who have done basic training in accordance with STCW requirements ashore are fully trained experts who can deal with any situation on board,” says Monk. “Someone who completed a course ashore five or more years ago will not be up to speed on the latest technology, regulations and procedures.”

The 29 metre Reine d’Azur was destroyed after a fire broke out on board in August 2021

He points the finger at disinterested owners, captains with big egos and ill-informed management companies, all more interested in sending crew on coffee-making courses than tuning up their safety skills. Magney goes further with characteristic bombast. “The average deckhand gets more product and training time provided to them on how to polish stainless steel in the course of a month than they do for dealing with a LiPo battery fire in a year and more.”

They claim that around half of yachts do not budget properly for training, and put the annual shortfall at millions of dollars. If just five per cent of the management budget were spent on training, it would make a difference, but the gold standard would be closer to 10 per cent. “It’s more of bad fiscal management by managing companies and crew alike,” Magney reckons.

Captain and marine projects consultant Chris Andreason agrees that training is the answer to mitigate a disaster with lithium and any emerging threats. “Captains have to deal with skill fade, new crew, time pressure and the emergence of new equipment,” he says. “If you as captain are trying to juggle 100 balls at once, you and your officers will always make sure you are compliant but may not have the time to do any additional training. However, if external training is in the budget from the vessel startup, with a refresher course after every yard visit, then it is more likely to be acceptable to the management team. Owners will understand that increased crew training brings more confident and competent crew, leading to a better, safer onboard experience for themselves.”

First published in the February 2023 issue of BOAT International. Get this magazine sent straight to your door, or subscribe and never miss an issue.


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