Everything You Need to Know About Trolling Motor Batteries

Posted May 11, 2020

What Are Trolling Motor Batteries?

Trolling motor batteries are specially designed batteries for a boat trolling motor. The purpose behind them is to provide electricity over a more extended period of time when slow trolling through fishing areas.

In contrast, boat starting batteries are used for starting the ignition. With marine batteries, it is necessary to start the engine and then provide enough power to sustain the motor and devices connected to the boat.

To better understand what trolling motor battery you should choose, it is vital to understand the different types of batteries that are offered.

Dual Purpose Batteries or Deep Cycle Batteries

Due to the need for a consistent energy supply, you should choose a dual-purpose battery or a deep cycle battery.

Both of these are separate from a starter battery found in automotive engines. They provide steady and consistent power supplies to keep your engine running over a longer timeframe.

A dual-purpose battery provides enough power to start the engine and turn it over, while also providing enough energy to keep your trolling motor running consistently. As the name implies, dual-purpose batteries can be used for both purposes.

Deep cycle batteries are a little different. They are designed to provide stable energy to your trolling motor over a longer timeframe. They will provide exceptional performance when used with a trolling motor.

It depends on what you are looking for; you can get the best of both worlds with the dual-purpose motor. If you are looking for a battery that will last longer in your trolling motor, then check out the deep cycle batteries.

Lead Acid Wet Cell or AGM

Lead-acid wet cell batteries are one of the most common types of batteries to use with trolling motors. They are an affordable option that can handle the everyday uses of a trolling motor. They typically last around 2-3 years and may require some sort of maintenance.

The wet cell is referring to the cells in the battery submerged in a mixture of sulphuric acid and water. The maintenance comes in when the battery is being frequently overcharged, causing the water levels to drop. It is recommended to check your battery before use, to make sure enough water is in the battery. If your water is running low, add distilled water to prevent the battery from being damaged.

AGM batteries stand for Absorbed Glass Mat. These types of batteries are completely sealed, unlike the lead-acid wet cell batteries. These batteries are a more expensive option but do not require any maintenance on them. AGM batteries will typically last 3-4 years, a little bit longer than the wet cell batteries.

An Even Better Option

If you are looking for the ultimate option, it would be worth your time to look into lithium trolling motor batteries. Lithium batteries are superior to both lead-acid wet cell and AGM batteries. They offer a longer life span and the ability to deep cycle while maintaining power with no maintenance.

When compared to lead-acid, lithium marine batteries can last up to 10 times longer while still providing 80 percent rated capacity over 2,000 miles. The fast charging time will make sure you are getting the most out of your adventures.

Lithium batteries provide superior energy when compared to the other options and are about half the weight.

Some of the other significant benefits of lithium trolling motor batteries include:

  • Longer shelf life
  • Constant power
  • Temperature resistant
  • Fast charging
  • No maintenance
  • Lightweight
  • Safe & Non-hazardous

When comparing deep cycle batteries lithium marine batteries are a smart investment.

What Specifications to Look For?

The battery specifications can alter your experience dramatically. There are so many batteries on the market claiming to be the best, but how do you know which ones are?

Amp Hour Rating

Like a fuel tank gauge, the amp hours will determine how long your battery will last. The amp-hour provides a measurement of charge within your trolling motor battery.

A higher amount of amp-hours will provide energy to your trolling motor for a longer time. This is one of the most important specifications to look for when considering a new trolling motor battery.

It is recommended to have at least 100 amp hours for use in trolling motors to ensure your battery won't fail. But higher amounts, for example, a 125 amp hour battery will last longer. It depends on what type of needs you have to determine what amp-hour would be best suited for you.


Standard deep cycle batteries usually are 12 volts. It is recommended to check your power system to determine if more voltage is required. Some power systems require 24 or even 36 volts like the RB36V40.

To learn more about how to calculate your energy needs and find the optimal battery for your application and usage, visit our Lithium Battery Selector Tool.

Helpful Tips

When it comes to choosing a trolling motor battery, it depends on how you plan to use it to determine the best fit for you. If you would like to get the most out of your trolling motor and avoid any maintenance, it is recommended to invest in lithium batteries.

Some helpful tips to maintain your lithium battery include:

  • Charge batteries after each use
  • Store batteries in a cool, dark place so your battery will not drain out
  • Make sure to check for corrosion before use
  • Do not ever mix batteries

Battery corrosion can dramatically reduce the power output of the trolling motor. If you do have corrosion, you can easily clean it with a mixture of water and baking soda.

Purchase Your Next Trolling Motor Battery

After completing this guide, you should have a good overview of what trolling motor batteries are and what they are being used for. Lithium is the superior option when comparing deep cycle batteries, offering lightweight and powerful energy.

If you are looking for a trolling motor battery, check out our selection, and we can help you make a decision that is right for you.