If you depend on your trolling motor for your on-the-water adventures, it is important to remember that without a functioning battery, you won’t be going anywhere. Here are some helpful tips on how to install, charge, maintain, and replace that trolling motor battery when needed.
Adding a trolling motor to almost any boat allows you to take your fishing adventures to a new level. You will be able to access areas previously too small for conventional motors. Or, on the other end of the spectrum, you’ll be able to take your kayak or inflatable boat further than you could previously paddle.
Trolling motors are also cheaper to buy and operate than other types of motors, but without a quality, reliable battery, you risk being stuck at home or stranded on the water. Keeping your trolling motor battery running in peak condition is key to make sure the adventures continue.
The first step to making sure your battery provides many long seasons of reliable service is proper installation. Installing a trolling motor battery is not difficult, but not doing it correctly can cause some serious problems later.
Choose the Correct Battery
You cannot just buy any old battery and expect it to be compatible with you trolling motor. You need either a deep-cycle marine or absorbed glass mat (AGM) design. Both are designed to withstand the frequent charging that will be required, and while an AGM battery will last longer, it does cost more up front.
Select the Right Location
Most batteries will be installed near the motor as this simplifies wiring. This may be on either the bow or stern depending on whether the trolling motor is the primarily motor on a small boat or an auxiliary power for a larger one.
Regardless of where it may be, the battery should be protected from weather and water as much as possible and not be sitting directly on a metal deck.
Safety and Security
In most cases, you will need two additional items: a battery box and a security strap. These two pieces will not only help protect against theft but also help keep out weather and prevent dangerous movement during operation. It is important to note that many jurisdictions require all boat batteries to be secured in this manner.
If you own a trolling motor, you will quickly become an expert at charging the battery if for no other reason than that you will be doing it so much. You could learn through trial and error, but this can be expensive and sometimes dangerous, so let us help.
Obviously, you will need a charger. We recommend a quality, automatic model with a trickle-charge setting. These will provide many years of reliable service, do not require constant attention, and can also be used for many other purposes.
Slow and Steady
There are two things you want to avoid when charging any battery. First, never do it to fast. Second, never overcharge the battery. Both can cause damage and shorten the life of the battery and hamper its ability to hold a charge.
An automatic charger set on trickle charge will avoid both by providing a slow, steady charge and shutting down when the proper power level is reached.
Your battery should be charged after every use. Like the batteries in many electronic devices, deep-cycle and AGM batteries can both develop problems achieving a full charge if run repeatedly at low levels.
Plus, a battery that’s less than fully charged is more likely to quit working when you need it the most, like when you are miles downstream from the launch.
Aside from regularly charging your trolling motor battery, the biggest thing you can do to ensure it lasts for many years to come is simple preventative maintenance. A few simple steps every few uses and prior to offseason storage will lengthen the life of the battery and make sure it is ready to go every time you need it.
A well-maintained battery should easily last three to five seasons, maybe even longer.
Every time you use your battery, give it a quick check for leaks, damage, or other signs that it may not be functioning at 100%. You also want to check the connections to ensure they are tight and free of corrosion.
Once a month, you should pull the battery and perform a thorough inspection and cleaning. Do this more often if you see corrosion developing.
Start by disconnecting the battery cables and removing the battery from the storage box. Clean both the battery and the box with water and mild detergent to remove any sand, dirt, or debris. Then allow them both to dry.
Now you want to check the battery itself for any damage, leaks, bulging, or any signs of potential failure. Next, remove any corrosion from the cables and connections. I like to use fine steel wool, but check with the manufacturer for specific recommendations.
Check all the cables, the box, and the security trap. Reinstall the battery, tighten connections, and add a thin coat of petroleum jelly to connections to prevent corrosion.
End of Season
In addition to the monthly inspection and cleaning outlined above, the end of the season brings with it some addition preventative maintenance. First, you want to fully charge your battery prior to storage. Remember, a partially charged battery will not last as long as one that you charge after every use.
Second, you never want to store a battery by sitting it directly on a dirt or concrete floor. Place it on a shelf or lay down some 2x4s to create a safe area for the long winter nap.
Never Use a Damaged Battery
If you notice any damage or leaks, or if your battery is not operating at its fullest potential, it is time to consider replacing the battery.
As previously mentioned, a well-cared-for trolling motor battery should last for several seasons, maybe even as long as 5 years. However, no matter how much you care for a battery, it will eventually reach the end of its useful life. It will be time to get a replacement.
What to Buy
You want to make sure you replace your existing battery with one of identical size, voltage, and connection style. Using an incorrect battery is potentially dangerous and is likely to damage your motor.
If you can no longer purchase the same kind of battery you used in the past, check with the manufacturer for a suitable replacement.
Follow the instructions above when installing your new battery. It is also recommended that you retain the receipt for warranty purposes and write the installation date on the battery itself for future reference.