Last time we talked about how to choose the proper type and size of battery for your boat, now it’s time to discuss how to charge and maintain your batteries. With the proper maintenance and charging, high quality boat batteries should last several seasons.

The first mistake most battery owners make is to wait a while before they charge their batteries. The quicker after use that a charger is put to a battery, the longer the battery will maintain it’s full capacity. A charger should be applied to a battery as soon as possible, preferably the same day.

A charger that delivers a slow or trickle charge is preferred to a charger that applies a quick, jump style charge. Deep cycle batteries are discharged slowly over time and need to be charged the same way.

On-Board chargers that mount right in the boat make this task easier, since there is no need to carry or hook up an external charger. Simply plug 110 volts into the on-board charger and it begins to charge your batteries. This feature makes on-board chargers standard equipment on most tournament boats and also great for fishermen that travel a lot.

On-board chargers are available in sizes that will charge 1-4 batteries and that put out 5-30 amps. As with batteries, get the largest charger your budget allows. You will definitely need to pick a charger that can charge all of your batteries. The only exception would be when using a single battery to start the outboard and do nothing else. In this case the alternator from the outboard will keep the cranking battery charged. If you use your cranking battery to power your electronics, you will want to charge it after every trip.

Most current on-board chargers also have a "smart" mode. This feature does two things. First, it allows all the chargers amperage to be channeled to where it is needed most. For example, a 3-bank charger with a 30 output would be great in a boat with a 24 volt trolling motor (2 batteries) and a cranking battery. When the charger is first turned on, each battery is receiving 10 amps. When the cranking battery is fully charged, the charger will automatically stop charging the cranking battery and send 15 amps to each of the 2 trolling motor batteries. Charging time is decreased when amperage is sent where it is needed most.

The second smart feature is the ability to leave an on-board charger plugged in for long periods of time, such as over the winter. In this case, the charger will maintain all batteries at a 90-100% charge all winter with no attention from the boat owner. The charger monitors the batteries and when they fall below a 90% charge, the charger will turn on and trickle charge them back to 100% then return to a sleep mode. This eliminates removing batteries in the winter to store them inside and guarantees healthy batteries come spring.

There are a few other options that make on-board chargers a little more convenient. An external charge indicator allows you to monitor the batteries condition during charging and an external 110-volt inlet makes it easy to plug in an extension cord every night.

Boat batteries are an expensive and important investment. Without them productive fishing trips are impossible. Protect this investment by properly charging your batteries with an on-board charger and they will last several seasons.

Next time we will discuss charging and maintaining batteries using your motor's alternator.

If you have any questions on batteries, battery chargers, or any other boat rigging items as well as information on walleye fishing, send me an e-mail at lance@walleye101.com.