David O´Neill originally had a background in boatbuilding and yacht design and has been working in the engineering side of the marine industry in Mallorca for over 25 years. Currently working in the team at Akupalma focused on supporting advanced marine energy projects.
Akupalma has been the largest battery supplier to the marine industry here in Palma for over 30 years and has recently moved all of its teams to a new office/warehouse in Son Moro. Their constant focus is education and support for installers and project managers.
With all of the advances in yachting at the moment, few subjects cause as much debate as `Lithium batteries´. Virtually every person on Mallorca is walking around with lithium-powered phones on them. In addition, there are countless tablets, laptops, headphones, and power tools at their homes with the same technology.
But in our industry, for every person who talks of the transformative power of these systems, there is another shouting “Fire, fire!”. We all want the environmental and on-board lifestyle changes that Lithium battery systems can bring to yachting. They offer reduced pollution, silent overnight running, hybrid solutions, or even full electric. But are they safe? And why are we still seeing fires aboard – especially with yacht ‘toys´?
Everybody seems to be waiting for regulators or insurance companies to find a magic solution so we can feel more comfortable with this energy transition. But there are already things we can proactively do to improve and reinforce on-board safety.
A little calm investigation and knowledge go a long way to understanding the truth behind the bad stories we have seen in the past and help us to not make some of the same mistakes.
Not one product
The largest lesson out there is that lithium batteries are not one single product. Not even close. The huge range of items that lithium batteries are built into means there is a huge range of chemistries out there. Some basic knowledge of the strengths/weaknesses of the 3 main ones in our industry is very useful, if not crucial, to the safe handling of these products aboard. Especially when it comes to purchases of boat toys or main systems. Lithium batteries in their simplest form are really just condensed energy. We have already been handling different types of energy with fuels like diesel, petrol and flammable gases for over a hundred years, and the range of lithium solutions and their pros/cons, are similar to those of conventional fuels. There are 3 common lithium battery types we will see in daily (marine) life and equating them to conventional fuels is a good way to get your head around the subject.
All batteries can be handled safely if you know what precautions you should take, but we do need to treat them with respect, as we have done in the past with conventional fuels.
`Li-Po´ Lithium-Polymer is at the extreme end and is the butane/propane equivalent of the group. This battery needs very careful handling, just like propane does. Their extremely light weight and power density are what make them suitable for high-performance items such as radio-control drones and high-performance water toys such as E-Foils. Many manufacturers of the toys do not fit full-safety electronics, further pushing up the risk factor. Li-Po does not like being overcharged, physically mishandled or overheated. No equipment manufacturers are using Li-Po battery solutions for the actual yacht, as their extreme lightness is not relevant if safety is compromised. But guests and owners will bring these on board, not knowing the risk involved. If you have these on board, know where they are and treat them well. Keep them cool when being charged, or stored, and keep them in a fireproof Li-Po bag. These bags are readily available online.
`Lithium NMC´ often just branded `Lithium-Ion´ is the `petrol´ of the group. This has been used for many years in car power packs, phones, power tools, etc. It is light weight and packs a big punch. This was the first mass-market battery and is still the most common lithium solution out there. With the correct original manufacturers’ chargers and protection systems, these make a reasonable choice. In most markets, this is also the cheapest option, hence why it is in so much equipment. But the electrolyte chemicals inside an NMC battery can combust if radically overcharged, shorted or overheated, hence why they have dedicated chargers and serious protection systems. They must never be used with incorrect chargers or handled without respect for the energy they contain. Early yacht batteries were this chemistry.
‘LiFePo4’ Lithium-Iron-Phosphate (LFP) is the `diesel´ of the bunch. A little less power dense than other choices, this chemistry is what most of the main superyacht suppliers have been building their service battery packs with for the past few years. The reason for this is simple – safety. It is not so common in the yacht toy market as it is still a bit more expensive and bulkier than NMC. LFP is a robust and fantastically stable solution that gives the benefits of massive power storage while focusing on safety as its first priority. The LFP batteries are inherently stable, so even quite serious mistreatment cannot start a fire from the battery itself. When combining this stable chemistry with the monitoring and charging protections developed for earlier chemistries, it’s a really safe installation option. This is why all of the main marine players have gone this way. Fires and boats do not make a good combination and the manufacturers all know that. Their target is similar to ours – enable a change of life on board, but safely.
The current state of affairs and confusions
We have all heard horror stories in recent years about lithium fires on yachts. But when investigating further, it is almost always found that it is nothing to do with the boat’s main batteries or core systems. A check through recent incidents shows that most yacht fires are starting in lazarette/garages, cabins and salons – not where we have the boats’ main systems. The fire is nearly always caused by the toys, the LiPo or NMC hoverboard the crew uses for shopping, the e-foil bought by a guest for the boss, etc.
Most people think of a battery from a water scooter as a glorified AA battery for a torch, but this is very far from the truth. If you mentally think of LiPo and NMC as similar risks to propane and petrol, you will start to appreciate that it is a serious chunk of energy. Petrol can be handled safely, but it is dangerous if handled carelessly. We must treat high-power batteries with the same sort of respect, as they can contain similar energy and capacity for damage.
So, as a first step in safety, we need some simple ideas and handling tips to limit -or stop- the chaos caused by these secondary batteries.
- When buying new equipment, what should you look for? What type of batteries do you have on board? And are you looking after them correctly?
- When purchasing toys, always check what type the batteries are and buy the version with the safer chemistry where available. Even going from Li-Po (butane) to NMC (petrol) is safer, but where possible always go for LFP.
- A more advanced charger with multiple connections on the cable to the battery is also a sign of safety and a monitoring system possibly being installed.
- Always stick to known high-quality brands with a proper reputation. Cheap/unknown equipment can be a very bad safety risk.
- Be super careful with any Li-Po equipment and batteries. It doesn’t matter if it is just a very small battery for the boss’s drone – its capacity for damage is huge. The Radio Control world has been using these for years and is why they invented Li-Po bags. The normal practice is Li-Po batteries are charged in metal boxes or Li-Po bags. Do not recharge anywhere near flammable surfaces or equipment.
- Nearly all fires happen while recharging. Only ever use the original manufacturers’ chargers. Fast charging stresses the batteries more, so use slow chargers, where practical. Make sure the chargers and connectors are not damaged or corroded. For smaller batteries or batteries out of the toy, recharge the pack inside a fireproof Li-Po bag or metal area, when possible. Recharge in an area where crew can monitor the process, especially when fast charging.
- If there is any sign of strange smells, popping noises, swelling, high heat or damage to the batteries or chargers – get them off the boat immediately! These are serious warning signs. Do not just hope it will magically fix itself. Never try to reuse faulty equipment until it has been fully checked ashore.
- Where possible, store all spare batteries somewhere that they cannot be physically damaged or corroded. Somewhere cool, flameproof and dry is best, such as a metal cabinet or larger Li-Po bag.
- Store the toys carefully. Do not leave battery-powered equipment to get hot in direct sunlight for long periods, or soaked in salty humid lockers. This is just asking for trouble. It will be overheating the batteries or damaging the electronics that monitor safety. We have all seen equipment left in the sun or shoved in a locker under a pile of wet dive gear. We have to stop treating equipment this way as this sort of carelessness is what causes fires and/or serious damage.
All modern high-power lithium batteries contain seriously condensed energy. We can safely use that to increase our freedom and lifestyle on board but -the same as diesel, petrol, and propane- we need to handle these products with the respect they deserve.
So are lithium batteries saint or sinner? The answer is down to our care and professionalism.
