What is the Best Battery For a Trolling Motor [Type & Size]

the Best Battery For a Trolling Motor

Selecting the appropriate battery size for your trolling motor is crucial for optimizing performance and efficiency on your boating adventures. This detailed guide will cover all the essential factors to help you identify the ideal battery size tailored to your specific boating needs.

Understanding Trolling Motor Batteries

Types of Trolling Motor Batteries

Trolling motor batteries play a vital role in the efficient operation of electric trolling motors, supplying the essential power needed to propel your boat. The choice of battery can significantly influence your boating experience.

Generally, trolling motor batteries are available in three main types: lead-acid, AGM (Absorbent Glass Mat), and lithium-ion (LiFePO4) batteries. Let's delve into the specific advantages and disadvantages of each type.

Lead-Acid Wet Batteries

The lead-acid wet cell battery is the most prevalent type used for trolling motors, resembling car batteries and having been a market staple for many years. Although some are specifically designed for deep cycle marine use, they are not fundamentally different from standard car batteries. Despite their availability, they are considered outdated technology compared to more modern options.

Opting for a lead-acid wet cell battery for your trolling motor necessitates careful consideration and adherence to specific precautions before purchasing and installing. The installation must be done with caution and in the correct sequence.

One of the main concerns with lead-acid wet cell batteries is the potential for acid spillage when filling with distilled water, posing hazards to you, your boat, and the environment. Although these batteries are economical and effective, their use is generally discouraged for marine applications due to safety concerns.

Advantages of Lead Acid Wet Batteries:

  • Affordable
  • Widely available
  • Easy to find replacement parts
  • Can handle shallow discharges


  • Require regular maintenance, such as filling with distilled water and cleaning terminals
  • Shorter lifespan compared to other battery types
  • Heavy and bulky

AGM Batteries

AGM (Absorbent Glass Mat) batteries have become the preferred option for marine applications due to their advanced design and enhanced safety features. Unlike traditional lead-acid batteries, AGM batteries are fully sealed and spill-proof.

The primary distinction lies in their internal construction. While lead-acid batteries rely on hydrochloric acid and lead plates, AGM batteries use absorbent glass mats combined with a gel-like substance to facilitate the necessary chemical reactions for storing electrical energy. This design not only enhances performance but also eliminates the risk of leakage, making them a reliable choice for various applications, including bass fishing in wet conditions.

The sealed nature of AGM batteries is vital for their longevity and safe operation. In contrast, even a slight loosening of a cell cap in a lead-acid battery can lead to leakage. This concern is nonexistent with AGM batteries, making them a preferred choice for those seeking a dependable, low-maintenance power source.


  • Longer lifespan compared to traditional lead-acid batteries
  • Virtually maintenance-free
  • More resistant to vibration and shock
  • Can handle deep discharges


  • More expensive than traditional lead-acid batteries
  • Still heavy

Lithium Batteries

Lithium batteries are celebrated for their exceptional power and remarkably lightweight construction. One of their standout features is their stable power discharge curve, which maintains consistent peak performance right until the battery is completely drained. For instance, a typical 12V 100Ah lead-acid battery weighs between 60-70 pounds, whereas the Timeusb 12V 100Ah LiFePO4 lithium trolling motor battery weighs only 21 lbs.

Compared to traditional batteries, which can be bulky and heavy, lithium batteries are compact and can easily fit into tight compartments. They come in various sizes and amp-hour ratings, allowing boat owners to select the ideal battery for their specific requirements.

For kayak fishing enthusiasts, lithium batteries are highly recommended due to their compact size and lightweight nature, which have minimal impact on the kayak's performance. Although they come with a higher price tag, lithium batteries are widely regarded as the best option for most kayak setups. In fact, many of the top trolling motors for kayaks are now equipped with lithium batteries.

Despite their higher cost, lithium batteries are becoming increasingly popular for trolling motor applications.


  • Longer lifespan in contrast to traditional lead-acid batteries.
  • Lightweight and compact
  • Maintenance-free
  • Can handle deep discharges


  • Expensive
  • Requires specialized charging equipment
  • May not be compatible with all trolling motors on the market

In conclusion, choosing the right trolling motor battery requires careful consideration of factors such as cost, lifespan, and maintenance requirements. Lead-acid batteries are economical but necessitate regular upkeep. AGM batteries, while more costly, provide a longer lifespan with minimal maintenance. Lithium-ion batteries represent the most advanced option, delivering superior performance at a higher price. By weighing the advantages and disadvantages of each battery type, you can make a well-informed decision to select the ideal trolling motor battery that best suits your needs.

Factors to consider when choosing a trolling motor battery

When selecting a trolling motor battery, it's essential to consider several key factors beyond just the battery types. One crucial aspect is battery capacity, measured in ampere-hours (Ah), which indicates the amount of energy the battery can store and deliver to the motor. Higher capacity batteries provide longer run times but are generally heavier and more expensive.

Another important factor is battery voltage, which must align with the power requirements of your trolling motor. Most trolling motors operate on either 12-volt or 24-volt batteries, depending on their power needs. Using an incorrect voltage can damage the motor or impair its efficiency.

For trolling motors with up to 55 pounds of thrust, a single 12V battery is adequate. Motors generating up to 80 pounds of thrust require two 12V batteries connected in series to provide 24 volts. The most powerful trolling motors, producing over 80 pounds of thrust, typically need three 12V batteries wired in series to achieve 36 volts. For more details, you might want to explore configuring LiFePO4 lithium batteries in series and parallel to optimize your setup.

the weight of boat and battery size needed

It's also crucial to consider that some trolling motors are designed to work specifically with certain types of batteries. Therefore, always refer to the manufacturer's recommendations before purchasing a battery to ensure compatibility.

Maintenance is key for all battery types. Lead-acid batteries require regular upkeep, such as checking fluid levels and cleaning terminals, to maintain performance and extend lifespan. AGM batteries need less frequent maintenance but should still be periodically checked for charging and storage conditions. Lithium-ion batteries require minimal maintenance but must be charged with a compatible charger to prevent damage.

Choosing the right battery for your trolling motor depends on your specific needs and budget. Evaluate factors such as capacity, voltage, and compatibility with your motor, and weigh the pros and cons of each battery type. Regular maintenance can significantly extend your battery's lifespan and ensure optimal performance.

What Size Battery is Suitable for Trolling?

How Does a Battery Size Affect a Boat’s Performance

Selecting the correct battery size for your boat is essential to ensure optimal performance and safety on the water. The battery size significantly impacts the boat's electrical system, engine efficiency, fuel consumption, and overall stability. Using an incorrectly sized battery can place undue stress on the engine, leading to increased fuel consumption and potential damage to the boat's electrical components, which could result in appliance malfunctions and hazards like fluid leaks, sparks, or overheating.

Both oversized and undersized batteries can adversely affect the boat's performance and the battery’s lifespan. Oversized batteries can overload the electrical system, possibly causing damage and reducing overall efficiency. Conversely, undersized batteries might not supply enough power to meet the boat's electrical demands, resulting in shorter run times or complete power loss.

It is crucial to consult with experts or refer to the boat manufacturer's guidelines to determine the appropriate battery size for your specific boat model. When selecting a battery size, consider factors such as the power requirements of your electrical systems, the desired run time, weight distribution, and your budget. Taking these aspects into account will help ensure that your boat operates efficiently and safely.

Factors to consider when choosing the right battery size

  1. Boat Size and Weight: The dimensions and weight of your boat are critical in selecting the appropriate battery size for a trolling motor. Larger boats necessitate batteries with higher amp-hour (Ah) ratings to supply sufficient power for longer durations of use.
  2. Trolling Motor Thrust: The thrust rating of your trolling motor is another essential consideration in determining the required battery size. Motors with higher thrust ratings need more power, which means a battery with a larger capacity is necessary to meet the motor’s energy demands effectively.
  3. Fishing Conditions: Environmental factors such as wind strength and water currents can greatly impact the power requirements of a trolling motor. In conditions with strong winds or currents, the trolling motor requires more power to maintain performance, thus necessitating a larger battery size to effectively handle these increased energy needs.

Battery Size for Trolling Motor

The most prevalent battery group sizes for trolling motors are 24, 27, and 31. However, determining the appropriate size depends on factors such as your boat's dimensions, cargo weight, and the power requirements of the motor.

For smaller boats with lighter loads and less potent motors, a group 24 battery might suffice. Group 24 batteries typically measure approximately 10 x 6.88 x 9.94 inches and offer a capacity of around 70-85 Ah. Notably, the Timeusb group 24 LiFePO4 battery boasts a capacity of 100Ah.

Timeusb Group24 lithium battery vs Group24 Lead acid battery

For larger boats carrying heavier loads and featuring more robust motors, a group 27 or 31 battery may be necessary. Group 27 batteries typically have dimensions of about 12 x 6.75 x 8.88 inches and provide a capacity ranging from approximately 90-105 Ah. Conversely, group 31 batteries are larger, with typical dimensions around 13 x 6.81 x 9.44 inches and a capacity ranging from 100-125 Ah. Below is the BCI battery size format for your reference.

Timeusb lithium battery group size chart

Advantages and disadvantages of using larger or smaller batteries

Opting for a larger battery undoubtedly yields more power and extended run times for the trolling motor. However, the drawback lies in the increased weight and bulkiness of larger batteries, which can potentially impact the overall performance and maneuverability of the boat.

Conversely, smaller batteries are lighter and more manageable, but they may lack sufficient power for prolonged use. Hence, striking a delicate balance between battery size and the boat's weight, thrust capacity, and prevailing fishing conditions is crucial to ensure optimal performance.

Therefore, finding a battery that achieves the ideal equilibrium between size and performance, considering factors such as boat weight, thrust capacity, and fishing conditions, becomes imperative. Upgrading to a LiFePO4 battery offers a solution, renowned for its high energy density and lighter weight, presenting an optimal balance of power and maneuverability.

lithium battery vs lead-acid battery

Battery Maintenance and Care Tips

Guaranteeing the peak performance, durability, and safety of your electric trolling motor system relies on giving top priority to the maintenance and care of your trolling motor batteries. Below are some tips and guidelines to assist you in this endeavor:

Charging Techniques:

Using a charger specifically designed for your battery type is crucial to ensure peak performance and prevent potential damage. Ensure that the charger matches the voltage of your battery. If you're uncertain, refer to the table below for guidance. To prevent shortening the battery's lifespan or causing damage, avoid overcharging. Charge the battery after each use and refrain from leaving it in a discharged state for prolonged periods. Can a LiFePO4 battery be charged using a standard charger? Continue reading to discover the answer!

Battery Storage Tips

Maintaining proper storage conditions for your battery is essential to preserve its lifespan and performance. Store the battery in a cool, dry location, shielded from direct sunlight and extreme temperatures.

Additionally, it's advisable to disconnect the battery from the trolling motor before storage. For flooded lead-acid batteries, ensure that water levels are adequately maintained. If storing the battery for an extended period, fully charge it beforehand and periodically recharge it.

Signs of a Failing Battery

Staying alert to signs of a failing battery is crucial to prevent safety hazards and uphold optimal performance. These warning signs may include challenges in starting the trolling motor, diminished power output, sluggish or incomplete charging, swelling or distortion of the battery casing, and leaks or corrosion near the terminals. If any of these indicators emerge, it may indicate the necessity for battery replacement or the need for professional intervention.

Choosing The Right LiFePO4 Battery for Your Trolling Motor

Voltage of Motor Motor Thrust Recommended Max Amp of Batteries Recommended LiTime LiFePO4 Batteries Recommended Reasons
12V 20 ~ 30 lb 50A Timeusb 12V 50Ah Lithium Battery Cost-effective
12V 30 ~ 70 lb 100A Timeusb 12V 100Ah Lithium Battery Cost-effective, Low-temp, Lighter
24V 70 ~ 100 lb 100A Timeusb 24V 100Ah Lithium Battery Cost-effective
36V 100 ~ 120 lb 100A 3* Timeusb 12V 100Ah Lithium Battery 3 batteries in series

This table is a concise table presenting the recommended Timeusb LiFePO4 lithium batteries, categorized by motor voltage, motor thrust, and the maximum recommended amperage of the batteries. Each recommendation includes comprehensive justifications. Explore Timeusb Trolling Motor Batteries to discover and select your ideal battery.


In summary, choosing the appropriate battery size for your trolling motor is paramount to achieving peak performance and longevity. An incorrectly sized battery can result in reduced power output, shortened battery lifespan, and potential safety risks. Thus, it's vital to factor in considerations such as motor thrust, boat weight, and usage patterns when determining the optimal battery size.

As previously discussed, adhering to the manufacturer's recommendations or seeking advice from knowledgeable experts is the best approach to selecting the correct battery size. Moreover, diligent maintenance and care are essential, including following charging, storage, and maintenance guidelines provided.

By carefully considering battery selection and practicing proper maintenance, you can enhance the efficiency and reliability of your trolling motor system. Therefore, don't underestimate this crucial aspect of your boating experience; choose the right battery today! Discover the power of LiFePO4 and share a 6% discount link with your friends and family from Timeusb.