Your boat is stationary, but that doesn't mean the battery doesn't need attention. Consumers can remain switched on, and the correct storage and charging strategy varies by battery type. If you want to properly prepare your boat battery for winter, start with the manuals for the battery, the charger, and the electrical system. These eight tips will help you create a practical inspection plan.
Tip 1: determine which battery you have on board
Note the brand, type, system voltage, and the function of each battery. A starter battery has a different task than a service battery. Even among boat batteries, there are different technologies. AGM and gel fall under lead-acid, while lithium batteries have their own charging and storage instructions. Therefore, do not automatically apply winter advice for one type to the other.
Tip 2: follow the manufacturer's storage instructions
Check the state of charge, environment, and inspection frequency specified by the manufacturer for long-term storage. There is no universal charge percentage that suits every battery. Also pay attention to the difference between the permitted storage temperature and the permitted charging temperature. Especially with lithium systems, it is important to check what the battery and the battery management system allow at low temperatures.
Tip 3: map out parasitic drain
An alarm, monitor, or other device can continue to use power while you think everything is switched off. Therefore, make an overview of the necessary and non-necessary consumers. Do not simply switch off the entire installation: a bilge pump or security system may need its own power supply. If in doubt, have someone check which circuits must remain active.
Tip 4: choose a battery charger that suits the system
Do not choose battery chargers based on brand or power alone. System voltage, battery technology, battery capacity, charging profile, and the conditions at the installation site play a role. Check which combination the battery and charger manufacturers declare suitable. An incorrect setting cannot be solved by simply leaving the charger connected for a shorter period.
For guidance, you can view the product information of the Victron battery charger IP22 12V or the Victron battery charger IP65 24V. These are not interchangeable choices: check the system voltage and suitability for your battery type and setup, among other things.
Tip 5: inspect the battery, cables, and connections
Look for visible damage, loose mounting, corrosion, and damaged cable insulation. Keep the environment clean and dry according to the installation instructions. Do not place metal tools or loose parts on a battery. Do not continue to use a battery with leakage, deformation, or other obvious damage, and have it assessed by a specialist.
Tip 6: determine if the battery can remain on board
A battery does not need to be removed in every situation. The right choice depends on the storage instructions, the boat installation, and the storage conditions. If the battery needs to be removed, have an expert safely disconnect and remove it if in doubt. Place a loose battery securely in a suitable place and protect the connections against short circuits.
Tip 7: assess shore power and supervision together
Remaining permanently connected is not the right solution for every setup. Check if the charger is suitable for the intended use and discuss the power supply with the marina or storage facility. Check the condition of cables and shore power connections. Do not use damaged plugs or improvised connections. Ensure that someone can check the installation during the winter.
Tip 8: plan inspections and keep records
Note when you check the battery and what readings you see. A suitable battery monitor can help provide insight, but its value depends on correct installation and settings. A standalone voltage measurement does not reliably tell the full state of charge for every battery type and under all circumstances. Have unexplained discharge investigated.
Does a boat battery need to stay on the charger all winter?
Not automatically. That depends on the battery type, charger, charging program, consumption, and storage instructions. Follow the manufacturers' instructions instead of a general recommendation to charge every battery continuously. Agree on who will perform inspections when you do not come on board for a long time.
Start the new boating season well prepared
Know your battery type, check the installation, and choose a suitable storage and charging strategy. View the battery, battery charger, and battery accessory collections at Bootland. Check before purchase whether the products suit your boat and have specialist work carried out by an expert.