3 Tips For Choosing Trolling Motor Batteries

Trolling motors are an excellent low-cost option for getting out on the water without relying on your physical power for propulsion. Many boats also include trolling motors as a secondary propulsion method, and these typically work the same way. Electric trolling motors are typically the standard option on small watercraft, and these engines require power supplied by a bank of batteries.

If you're new to the world of boating, you might be confused by the many options available. Selecting the best batteries for your trolling motor is crucial to getting the most power and life out of it, so it's one of the more critical equipments selection decisions you'll need to make. These three tips will help you to find the best batteries for powering a relaxing day on the water.

1. Don't Ignore Weight 

Weight is a concern on any small watercraft, but it can be crucial to consider when using an electric trolling motor as your primary propulsion method. Since the output of these engines can be relatively low, adding too much weight can significantly impact their performance. Depending on your battery configuration, your battery bank may add the weight of several people to your boat.

Since lead-acid and AGM batteries can weigh over 60 lbs., you'll need to consider your battery bank's total weight carefully. If you're installing multiple batteries to power your engine, going with an option that saves a few pounds can add up. Although expensive, lithium-ion batteries can also be a practical choice if you need to shave a few pounds.

2. Understand the Relationship Between Motor Specs and Amp Hours

Deep cycle batteries come with a rating in amp-hours. This value can give you an idea of how long your battery will last on the water. While there are a few other factors to consider, batteries with a higher amp hour rating should generally provide a longer motor runtime. If you know the amperage draw of your motor, you can divide this by your battery's amp hours to get a rough runtime estimate.

However, remember that conditions will affect your motor's power draw and your battery capacity. In colder conditions, the maximum capacity of your batteries may fall slightly. Likewise, your trolling motor will draw less power when operating at slower speeds or in calm waters. Always treat runtime calculations as estimates and leave yourself plenty of safety overhead.

3. Consider Warranty and Battery Lifetime

There's generally a direct relationship between battery cost and expected lifetime. Lead-acid batteries cost the least but tend to have relatively short lifespans. Lithium-ion batteries last the longest but cost much more. Finally, AGM batteries fill a middle ground for battery life and cost. You can typically expect battery warranties to track their expected lifespan.

When choosing your boat batteries, don't just consider the upfront cost. Paying more for a higher-end battery can mean getting more life, ultimately allowing you to save money if you intend to keep your boat for the long haul.