How to Plan Ventilation for a Boat Battery Compartment

How to Plan Ventilation for a Boat Battery Compartment: steps

Understand what you are venting for
Flooded lead-acid needs ventilation because charging produces hydrogen. LiFePO4 in normal operation does not. The reason to ventilate a lithium compartment is heat, and the consequences of a thermal event, not routine gassing.
Control temperature first
Keep the compartment out of direct engine heat and out of a sealed, sun-loaded space. Charging and discharging both generate heat, and an Australian summer already puts the compartment near the top of the pack's range.
Allow air to move around each pack
Packs pressed tightly together and against a bulkhead cannot shed heat from their faces. Leave the clearance the manufacturer specifies on all sides.
Check what the installation standard requires
AS/NZS 3004.2 governs the installation, and your insurer may have its own view. What is technically unnecessary for the chemistry may still be required of the installation.
Plan for the failure case
Consider where a venting pack would direct its gases and heat, and what is adjacent — fuel, accommodation, the escape route. This is the part of the question that actually matters.