Upgrading batteries

Treating batteries as a system works best

- WAYNE CANNING

For a very long time, high-capacity battery technology remained pretty simple. Wet cell lead-acid batteries were pretty much the only choice boaters had. Over the last 10 to 15 years, battery technology has advanced and more choices of battery design and type have developed. All batteries age, and at some point it becomes time to replace them. This is the time many consider upgrading to one of the newer types of batteries. This may seem a simple task at first, but there is more to consider when changing or upgrading batteries than just the batteries themselves. Batteries are part of a system that must work together to be truly efficient.

The battery system

When thinking about batteries for your boat, you must also consider how the batteries are to be used and recharged. Cabling and connecting the batteries to the boat electrical system, as well as how the batteries are mounted and secured, can also impact battery performance. How a battery is recharged has a large effect on the performance and life of a battery. Not all batteries charge at the same rate or voltage. Incorrectly charging a battery can greatly affect performance and shorten its life.

There will often be several charging sources on a boat, each utilizing a different technology. A typical cruising boat will have a battery charger used when connected to shore power or generator. Otherwise, charging is done via an alternator run off the propulsion engine. Solar and wind chargers will also likely be used. Each of these charge sources must be correctly configured to work with the type of battery installed.