Damaged Marine Lithium Battery: What to Do
Recognise damaged LiFePO4 batteries after impact, water ingress, overheating, swelling or electrical faults.
Stop using a battery that shows swelling, deformation, puncture, impact damage, severe overheating, leaking, smoke, unusual gas or odour, hissing, evidence of flooding or salt-water ingress, or fire exposure.
Do not recharge a damaged battery simply to see whether it recovers.
A large fixed marine battery should be isolated and assessed using the manufacturer's emergency instructions and a competent professional.
Diagnose before replacing parts
A shutdown or low-output symptom can begin in the battery, charging source, protection, cable path, monitor configuration or the load itself. Record evidence before resetting equipment so the original cause is not lost.
- Capture alarms, BMS history, state of charge, voltage at the battery and voltage at the affected equipment.
- Inspect for heat, looseness, corrosion, damage or water ingress before attempting another high-current test.
- Stop and isolate the system if there is swelling, unusual heat, odour, smoke, damaged cabling or repeated protection operation.
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