How to take care of your boat battery – professional guide

Hur du tar hand om båtbatteriet – professionell guide

A well-maintained battery is the foundation for a reliable and safe boating experience. Whether you have a lead-acid, AGM, or lithium-based battery, the same basic principles of care and maintenance apply.

Charging & Maintenance

  • Always charge the battery immediately after use – avoid deep discharge
  • Use a smart trickle charger (e.g., CTEK) during winter storage
  • Maintain a charge level between 50–100% for optimal lifespan
  • Avoid overcharging – choose a charger with automatic temperature compensation

Cleaning & Inspection

  • Regularly check the terminals for oxidation and corrosion
  • Clean the terminals with a solution of baking soda and water (1 tbsp per dl)
  • Apply terminal grease or contact spray to the terminals after cleaning
  • Ensure all cable connections are tight and in good condition

Winter Storage

  • Store the battery in a cool (5–15°C), dry, and frost-free place
  • Always disconnect the battery from the boat for extended storage
  • Charge to 100% before storage and check every 4–6 weeks
  • Avoid storing directly on concrete – use a wooden board or plastic pallet

Safety

  • Always work in well-ventilated areas – batteries emit hydrogen gas when charging
  • Wear protective gloves and safety glasses when handling battery acid
  • Keep open flames, sparks, and cigarettes away from the battery
  • In case of acid leakage – neutralize with baking soda and rinse with plenty of water

Signs that the battery needs replacing

  • Doesn't hold a charge for more than a few hours under normal conditions
  • Visible swelling, cracks, or leakage in the casing
  • Voltage drops quickly under load (below 12V)
  • The battery is older than 4–5 years and performs noticeably worse