How Long Does a Boat Battery Last?

OPTIMA Batteries
Harris Chain, Florida
If you're looking for a simple answer as to how long a boat battery will last, no one can give you an honest answer (although many will offer guesses). There are too many variables involved, from the boat itself, how the boat battery is used and how it is maintained. Many boat batteries do not see a hard life in terms of how they are used. However, they do often see a very hard life in how they are not used. In other words, many boat batteries are not properly-maintained and proper voltage maintenance of boat batteries will help maximize battery performance and lifespan. 

Fully-charged, most boat batteries will measure at least 12.6 volts (including the OPTIMA 34M BLUETOP). Some boat batteries, including the other OPTIMA BLUETOP batteries may not be fully-charged until the measure at least around 13.0 volts. Whenever any battery is discharged below 12.4 volts and is left sitting in that state of discharge, sulfation begins forming in the battery plates, which diminishes both battery capacity and lifespan.

So if proper voltage maintenance is the key to long boat battery lifespan, how can you accomplish that? By regularly using a quality battery charger or maintainer, even during boating season. Keeping voltage maintained while your boat is in storage is absolutely critical to making your boat battery last for a long time and could double or even triple battery lifespan.

What if you don't have access to electricity where you store your boat? Fully-charge the battery with a quality battery charger before you put it into storage and completely disconnect it, so it can't get discharged by anything in the boat while it is in storage. Then, when you bring it out of storage, fully-charge the battery again with a battery charger before you use it.

If the boat is going to be in storage for longer than an off-season (more than six months or so), be sure to check voltage and if the voltage drops below 12.4 volts, charge it up again to keep the voltage topped off.