Know the warning signs: battery safety and fire on an electric boat

This one is serious, so we will keep the jokes outside the safety lines.

Lithium batteries power almost every electric boat on the water, and the vast majority run for years without a problem. But when a damaged or badly installed battery fails, it fails fast. On a boat, where escape routes are short and water is all around, that matters.

The Boat Safety Scheme reports increasing numbers of fast-spreading fires caused by damaged or failing lithium-ion batteries, including near misses, fires and serious losses on boats (BSS). Here is what it and the Broads Authority advise.

Installation: get the foundations right

Most problems start here. The Boat Safety Scheme says:

• Installed lithium systems should be fitted by competent persons to suitable industry standards.
• Use batteries and components intended for marine installation.
• Install and use them according to the maker's instructions, within its safe operating limits.
• Do not connect different battery chemistries in parallel or in series.
• Tell your insurer, or risk being left uninsured.

Source: BSS. If you are buying a used boat, these are the first things to check. See buying a used electric boat.

Charging habits: the daily session

Charging is when most batteries are at their busiest. The safety advice is simple:

• Use only the maker's charger and cables.
• Do not leave batteries charging when you are asleep or away from the vessel, unless the instructions or installer say it is safe.
• Disconnect batteries once charging is complete.
• Charge larger portable batteries off the vessel where possible, on a stable hard surface, not on soft materials.
• Do not overload sockets.

Sources: BSS, Broads Authority.

The same goes for the smaller quiver on board: e-bikes, eFoil batteries, phones and power banks. The Boat Safety Scheme lists e-bikes, laptops, phones, vapes and electric watercraft among common sources of battery fires.

Warning signs: read the conditions

Check batteries routinely for damage. Stop using a battery and get it checked if you notice:

• Heat where there should not be any.
• A strange smell.
• Unusual noise, including loud popping, hissing or screaming sounds.
• Smoke or vapour.
• Swelling, cracks or other damage.

A damaged lithium battery can overheat, shoot out flames and explode. If a battery is damaged or no longer holds charge, take it out of use and have it recycled by a specialist (BSS).

If there is a fire: get out, stay out

Lithium battery fires can spread rapidly, and traditional fire extinguishers may not work. The Boat Safety Scheme's advice is clear:

1. Raise the alarm.
2. Warn others.
3. Get out.
4. Stay out.
5. Call 999 or VHF channel 16 for help immediately.

Do not go back aboard to save belongings. Outside the UK, call 112, the emergency number that works everywhere in the EU (European Commission), and use VHF channel 16 on the water.

Be ready before the set arrives

Prepare before anything goes wrong:

• Fit certified smoke alarms that can be heard throughout the boat, and test them monthly.
• Make sure everyone aboard knows how to get out.
• Keep escape routes clear.
• Keep good ventilation on board.

Sources: BSS, Broads Authority.

Our verdict: respect it, don't fear it

So, should a lithium battery keep you ashore? No. A marine battery, fitted properly and charged sensibly, is a safe way to power a boat.

What makes the difference is habit: the right charger, no unattended charging, a working smoke alarm and an escape plan everyone knows. Those few minutes are the best safety kit you will ever buy.

For storage advice, read winter storage for electric boats and electric boat battery care.