If you’ve fished a day on the water you know what it’s like for your trolling motor to slow down as you drift towards your best fishing hours of the day. A battery may not seem exciting, but it’s the difference between catching and going home. It can determine the success of your fishing tournament. Fortunately, battery manufacturers have been able to keep up with the new demands of anglers, and there are modern options that would have seemed impossible even five years ago.
This guide is meant for bass tournament anglers, kayak anglers, and inshore fishermen who prefer to fish from their trolling motor as opposed to using their outboard engine. It discusses the specifics of trolling motor batteries, the misinformed marketing from most competitors, the features that matter and why some batteries leave you high and dry when the fish finally are showing on the graph, and others help anglers extend their fishing days.
Real Numbers Associated with Trolling Motors
Amps are the most important factor pertaining to batteries and their size. The starting point is knowing how much energy a trolling motor battery consumes each day. Manufacturers rate their trolling motors by their draw in Amps. It is important to note peak draw and the real-world conditions that affect how much energy is consumed throughout the day, such as wind, current, boat weight, and the way the motor is used. Choosing the correct size trolling motor battery for your motor is important because it will determine whether you can feel confident fishing at your desired location.
Your Average Daily Consumption
An average bow-mounted trolling motor consumes 20 to 60 amps depending on the thrust setting, with brief spikes during motor starts or gusts of wind. Averaging about 30 amps, an 8 hour tournament draws 240 amp-hours of energy. This number eliminates borderline batteries and explains the trend of anglers who previously used a single group 27 battery, to now install batteries that are almost twice as large in the same space.
Deep Cycle vs. starting Batteries
At least once a year someone installs a starting battery in a trolling motor thinking it will work only to find it fails them for the season. Starting batteries are designed for a high energy draw that is recouped by the alternator and should never be deeply discharged. Deep cycle batteries are designed specifically for a high energy, long term draw. Understanding this difference eliminates the most common failure in fishing battery applications.
The Chemistry Behind Trolling Motor Batteries
The chemistry behind trolling motor batteries is important because it changes the weight of your boat, the price, and the time you spend fishing versus the time you spend watching the battery gauge. All trolling motor batteries have different use cases, but lithium batteries have changed the game the most because they have lower prices now.
Flooded and AGM Lead-Acid
Traditional deep-cycle marine batteries are still relevant, and are more cost effective, but are suitable for occasional use. AGM batteries are built to be strong and vibration proof, but come at an increased cost over flooded batteries. Everyone is familiar with the pros and cons of deep-cycle batteries. They are heavy and discharge at a rate that reduces motor power. These batteries can be worth it to the weekend fisherman who has a smaller boat.
Lithium Iron Phosphate for Days Long on the Water
Upgrades to lithium batteries for tournaments or serious recreational anglers have become standard, and the reasons for that quickly add up. The capacity of usable battery can nearly double when upgraded to lithium from lead acid meaning a 100 amp hour lithium battery does considerably more than a 100 amp hour lead acid battery. Lithium batteries are also significantly lighter, which becomes important for boat performance, towing with trailer, launching kayaks by hand, and fishing. Lithium batteries’ voltage also stays practically constant, and thus the batteries have nearly full control of thrust even after a lot of battery is used. This means a casters has the same amount of control while making the last cast as they do for the first cast. Companies like Vipboss integrate battery management systems into their battery packs for the added challenges of the marine environment and the high level of integration marine environments require.
Installation and Use on the Water
A battery is only useful with a good supporting installation. Marine environments have a lot of ways to punish poor installations, and details that may seem like overkill during the installation end up saving an entire fishing trip when the weather turns.
Wiring, Fuses, and Connectors
The loss of thrust from undersized wiring on trolling motor circuits is apparent, and serious current flows through those circuits. Tinned copper wire should be used for circuits in the range that is appropriate sized, and a fuse or breaker designed for the appropriate level of amperage should be placed no more than 7 inches away from the battery’s positive terminal to avoid problems that stop an entire fishing trip.
Onboard Chargers and Between-Trip Care
An expenditure once takes you from an old lead-acid unit to a charger that is appropriate for your battery bank and chemistry, and lithium batteries in particular need a lithium-specific charger. Using a lead-acid unit to charge a lithium battery either leaves the battery with an insufficient charge or causes the battery to go into protection mode. It is best to charge both lithium and lead-acid batteries on a regular basis (e.g., before going on a fishing trip). For this reason, having an onboard charger with a reporting capability via Bluetooth is beneficial, as you can verify your battery without having to load your boat for a fishing trip.
A Fully Concentrated Fisherman
The right trolling motor battery has the potential to take you from being a good angler to a great angler, as you will no longer worry about the battery going dead. When you are no longer thinking about battery capacity, you can focus on how to maximize your fishing potential. With lithium batteries, you no longer need to worry about battery capacity during the entire offshore fishing trip. With lithium batteries, you no longer need to worry about reducing power while trying to catch a fish during the afternoon hours, which is the reason many anglers use lithium batteries. However, if you use your trolling motor battery less than a few times a season, lead-acid batteries are a good option to consider. Ultimately, trolling motor batteries are an important consideration, and the right battery, charging equipment, and fitted battery size will solve your battery problems.
