Take care of your boat battery

When performing vessel safety checks, I ensure that the boat’s battery is secured and that at least one terminal is covered to prevent a metallic object from shorting out the battery and potentially causing a fire.

Batteries buried in the bowels of the vessel, under or behind other gear, makes inspection almost impossible. In such cases, you cannot ensure that the tops of the batteries are clean, the connections are tight or that a wet cell battery has sufficient fluid.

You should check the fluid level in wet cell batteries often. If low, fill the cells with distilled water. Clean any spilled water from the top of the battery before returning it to service. If the fluid level in the cells is below the tops of the plates, the battery’s life has most likely been compromised.

If you find corrosion on top of the battery or on one or both of the terminals, clean them using a small brush and a solution of one tablespoon of baking soda to a cup of water. To be safe, remove the battery and clean it away from the vessel while protecting yourself with either a face shield or safety goggles and gloves. Rinse off the baking soda mixture with running water, and dry the battery before returning it to the boat. Coat the terminals with petroleum jelly to prevent further corrosion. If you live in the North where it freezes in the winter, make sure your batteries are fully charged before winterizing. Using a hydrometer, take specific gravity readings of each cell to verify the battery’s state. A fully charged wet cell battery should read between 1.255 and 1.275 per cell. –Allan B. Furtado