Lithium Battery Safety for Marine Workshops

Why Marine Workshops Face a Different Lithium Problem

An owner handles one or two batteries they know. A workshop handles dozens it doesn't. That's the whole risk story, in one sentence.

A refit yard in Sicily, a battery tech in Palma, or a yacht management office in Antibes sees the stuff nobody else sees. The e-foil pack that got dropped on a passerelle. The jetboard battery that sat in a locker at 55 degrees all August. The Seabob that took a splash of seawater through a cracked seal. They all end up on the same workbench, and the workshop inherits the risk profile the OEM test data never covered.

The cells inside a damaged pack can look fine for hours, days, or weeks, and then go. Thermal runaway isn't gradual. Once it starts inside a cell, neighbouring cells follow within minutes, the casing vents hydrogen fluoride and hydrogen, and a typical 3 to 5 kWh e-foil pack can release enough energy to end a workshop. That's the scenario the LiVault RACLAN range and RAMBSS infrastructure are built to contain.

The four conditions that change a battery's risk class

A battery that's left an OEM-specified operating envelope isn't the battery on the datasheet any more. Treat it as a quarantine item until proven otherwise.

• Mechanical impact: the pack has been dropped, crushed, or dented. Internal cell separators can be compromised with no visible external damage.
• Overheat exposure: the pack sat above its OEM storage temperature (typically 45 to 60 degrees depending on chemistry) for any meaningful period. A closed tender garage in Malta in August hits that easily.
• Liquid ingress: saltwater or freshwater has reached the cells or the BMS. A short circuit can run silently for days before escalating.
• Unknown history: the pack arrives at the workshop without a clear service record. You don't know what it's been through, so you can't rule any of the above out.

The Raclan Box Quarantine Protocol

This is the procedure we give every workshop we supply. It's built around the Raclan Box (1.75 kWh total capacity, 24.7 kg, DMT TÜV Nord certified under programme M 02-2022), and it's designed to be repeatable by any technician on any shift.

1. Contain at source. A suspect pack goes into the Raclan Box at the vessel or the customer's premises, not after a drive across town. The Box (580 x 380 x 380 mm external) fits on the floor of most tender garages and service vans.
2. Transport inside the Box. The pack stays sealed in the Box between the boat and the workshop. The TRIDENT cooling system is already armed; if the pack heats up in transit, the Box triggers independently of external power thanks to its 12 V LiFePO4 backup.
3. Place, close, lock. Inside the workshop, set the Box on its rubber feet, close the door, turn the key to ON. The thermal sensors go live immediately.
4. Monitor for 24 hours minimum. A cell going into thermal runaway from mechanical damage can take hours to escalate. 24 hours inside the Box, with the door closed, is the baseline observation window before the pack is handled again.
5. Decide: return to service or write off. If the 24-hour window passes with no alarm, no coolant release, and no temperature rise above ambient, the pack can go to OEM-specified testing. If the Box triggered at any point, the pack is written off and handled as damaged lithium waste.
6. If the Box triggered: do not open. Once the TRIDENT coolant has released, the pack is submerged and the event is contained, but the cells inside are still reactive. Contact Ritz Marine and the OEM before opening. The Box is built for a refill service after use; the 5.5 litres of TRIDENT is the consumable.

The Box is certified for a maximum single battery capacity of 877 Wh and a maximum total capacity of 1,754 Wh including the charger. For anything above that, the bench workflow shifts to the RACLAN Square Marine Box or to an installed RAMBSS bay.

Installed Workshop Infrastructure: RAMBSS Modules

At refit-yard scale, the workflow moves from portable boxes to installed bays. RAMBSS modules are 600 x 600 mm footprint units (three heights: 500, 750, 1,520 mm), all stackable, all tied together into one workshop fire-safety system.

What a RAMBSS bay gives a workshop

• Module 500 at 4.35 kWh per-battery capacity (inside 550 x 550 x 300 mm); Module 750 and Module 1500 at 5.25 kWh each (inside 550 x 550 x 500 mm and 550 x 550 x 1,300 mm respectively). That covers every e-foil, jetboard, and tender pack on the market.
• Three thermal sensors per module, redundant electronics, and a water-resistant OLED touchscreen per unit. The tech sees module state at a glance.
• Integrated multi-nozzle extinguishing plus an external half-inch water connection for interval cooling. If a module triggers, the yard can keep cooling the battery through the cell-by-cell cascade window without opening anything.
• Exhaust with multi-stage toxin filtering: HF, explosive H2, and VOCs are filtered before exhausting the workshop. That's the difference between a contained event and a yard-wide evacuation.
• Six-week emergency power: the module keeps monitoring during any workshop outage. A long weekend power cut doesn't leave quarantined cells unmanaged.
• LAN, Wi-Fi, dry contact: module state ties into the yard BMS or alarm panel. A night-shift fault reaches the duty manager through the same channel as any other critical system.
• Lloyd's Register Design Appraisal: RAMBSS holds Lloyd's Design Appraisal Document TSO-24-013730-F01-DAD. It's the reference workshops use when insurers ask for evidence of certified containment.

Installation footprint

RAMBSS modules are 600 x 600 mm externally, with 20 cm clearance required upwards and 10 cm backwards. The door can be hinged right or left (clarify before ordering). A typical yard installation runs a single stacked column (Module 750 on top of Module 500) against a bulkhead, with wall connecting plates and floor fixing plates bonded or screwed into the floor. The housing is an explosion-proof, fire-retarded multi-layer composite; the inside is A1 fire rate (non-flammable).

We coordinate installation with local marine electricians across Malta, Sicily, Greece, and the wider Mediterranean. For larger yards (Palma, Antibes, Genoa, Viareggio), we work through the established refit network rather than shipping techs in.

Insurance, Liability, and What Your Underwriter Is Starting to Ask

A workshop that handles a customer's 3 kWh e-foil pack is sitting on more stored energy than most yards realise. That's changed how marine workshop insurance reads.

Across Europe, underwriters writing marine-industry cover now routinely ask three things at renewal: what lithium storage infrastructure you've got, what's certified, and how you quarantine damaged items. A yard that can answer those three questions with a documented procedure and certified hardware tends to hold its premium. A yard that can't, gets loaded, excluded, or non-renewed. MCA guidance in MGN 681 Amendment 1 covers the vessel side of this; the workshop-side equivalent is starting to show up in marine-industry policy wording.

The practical answer is the one we give every workshop we supply. Show the underwriter certified containment (DMT TÜV Nord certificates for Raclan products, Lloyd's DAD for RAMBSS), a written quarantine SOP built around the 24-hour rule, and a basic audit trail per pack handled. That's the package that closes the loop on insurer questions.

For more background on the vessel-side compliance regime and how it feeds back into workshop practice, our long-form piece on lithium fire safety boxes for yachts walks through the same standards from the owner's perspective.

The Three Products a Working Yard Needs

Portable quarantine, bench-top testing, installed capacity. One of each, specified against your actual throughput.

For the newer RAMBSS-2 and RAMBSS-3 configurations (larger stacked installations aimed at refit-hall deployments), see RAMBSS-2 and RAMBSS-3 on Ritz Marine.