This results in overcharging, which can boil the electrolytes dry in wet-cell and AGM batteries and harm gel batteries as well.

An overcharged battery will shed material from its plates and boil away its electrolyte, dooming it to a short, ineffective life.

The plates of an undercharged battery will get clogged with lead sulfite, requiring you to carry that battery to the recycling center early as well.

Using the right marine battery charger can help you avoid these problems.

If you fail to do it correctly, youll be forced to purchase a new boat battery.

For this reason, an important first step in buying a charger is to read all pertinent information provided by the manufacturer to determine that the one you purchase will be compatible with the type or types of battery youll be charging.

Chargers are offered in one-, two-, three- and four-bank (battery) configurations.

If you have 12 hours or more between trips, you may be happy with a lower-amp charger.

If faster charging is needed, a more powerful unit (10 amps and above) may be best.

If you have one engine, youll only need a charger with a single cranking-battery output.

Twin-engine applications, however, call for a charger with dual cranking-battery outputs.

Portables also are great when you need to charge batteries on several boats.

The old-fashioned trickle chargers most of us are familiar with fall into this category.

But state-of-the-art models like the Minn Kota Model MK110P Battery Charger with short circuitreverse polarity protection and LED displays also are available.

The best models are encapsulated with seal-tight materials that protect the unit from shock, vibration and moisture.

Good chargers also have automated charge sensors that detect the batterys voltage level to assure an optimum charge.

And because they are portable, they are subject to being stolen if you must use them in a motel parking lot, boat stall or other public place.

On-boards tend to be more expensive than portables, but they easily pay for themselves in convenience.

When you return home from a boating trip, you simply plug the charger into a 120-volt outlet and let the charger maintain your batteries without the hassle of personal monitoring.

An onboard charger is always hooked up and is only a plug-in away from charging your batteries.

Because its permanently installed, its more difficult for thieves to make off with.

And most importantly, on-board chargers are more technologically advanced units, providing multi-stage switching to manage and maintain a boats batteries during the charging process.

Cycling batteries this way as opposed to maintaining the charge tends to reduce battery life.

Additionally, linear models often are set at voltages too high for maintaining batteries.

Bass Pro Onboard Charger Manual