Choosing the Right Batteries: Outboard Motor VS Trolling Motor

Are you considering the switch to an electric boat motor for your marine adventures? As the world embraces sustainable energy solutions, electric boat motors have gained significant attention for their eco-friendly and efficient performance.

In this comprehensive guide, we'll explore the ins and outs of marine electric boat motors and the batteries that power them, helping you make informed decisions for your next aquatic journey.

Part 1: Understanding Marine Electric Boat Motors

1.1 What Makes Electric Boat Motors Unique?

Electric boat motors, unlike traditional gasoline engines, rely on electrical power to propel watercraft. These motors are known for their low noise, zero emissions, and low maintenance requirements, making them an attractive option for environmentally conscious boaters. With advancements in technology, electric motors now offer comparable performance to their gasoline counterparts, ensuring a seamless transition to sustainable boating.

1.2 Types of Electric Boat Motors

(1) Electric Outboard Motors

• These are the most common type of electric boat motors, designed to be mounted on the back (transom) of the boat.
• They come in a variety of power outputs, typically ranging from 3-50 horsepower or higher.
• Advantages include easy installation, compact size, and quiet operation.
• Downsides are limited battery power and travel distance compared to gas outboards.

(2) Inboard Electric Motors

• These motors are installed inside the boat, often in the engine compartment.
• Provide more power and longer range than outboard motors.
• Require more complex installation but allow for better weight distribution in the boat.
• Available in power outputs up to 200 horsepower or more for larger boats.

(3) Stern Drive Electric Motors

• Similar to inboard motors but with the drive mechanism positioned outside the hull.
• Offer some of the advantages of both inboard and outboard designs.
• Provide good power and range while maintaining a compact footprint.

(4) Pod Drive Electric Motors

• Innovative design with the motor and drive unit in a single, integrated pod.
• Mounted under the boat, often in pairs for better maneuverability.
• Allow for greater efficiency and precise steering control.
• Higher cost and complexity compared to other options.

(5) Trolling Motors

• Small, lightweight motors designed for precise slow-speed maneuvering.
• Mounted on the bow or stern, can be foot control, hand control and remote controle.
• Used in conjunction with a main propulsion system for fishing and precise boat positioning.

 Trolling Motor on Bow & Stern

1.3 Trolling Motor VS Outboard Motor

Outboard motors and trolling motors serve different purposes and are designed for distinct applications on boats.

1) Outboard Motors

Outboard motors are the primary means of propulsion for most boats. They are mounted on the transom (back) of the boat and are used to propel the vessel through the water.

LiTime 12V 100Ah Lithium Marine Outboard Motor Battery

Power: Outboard motors are available in a wide range of horsepower options, making them suitable for various boat sizes and types, from small fishing boats to large recreational vessels.

Features: They are designed for powering the boat at higher speeds and are essential for getting the boat to and from fishing spots, cruising, and water sports.

2) Trolling Motors

Trolling motors are secondary motors used for specific fishing techniques, such as trolling, where the boat moves at a slow, controlled speed to avoid disturbing fish.

Trolling motors are electric and are available in a range of thrust ratings, which determine their power and suitability for different boat sizes. Suggest reading: What Size Battery for Trolling Motor?

Trolling motors are mounted on the bow (front) or stern of the boat and are used for precise maneuvering, maintaining position, and quietly moving through the water, particularly in shallow or heavily vegetated areas.

LiTime 12V 100Ah Lithium Trolling Motor Battery with Bluetooth

3) Main Differences Between Trolling VS Outboard Motor

Primary Propulsion vs. Auxiliary Power: Outboard motors generally serve as the primary propulsion for most boats, particularly larger ones. However, on smaller vessels like kayaks, trolling motors can also function as the main source of propulsion. Typically, trolling motors are used as auxiliary motors for precise maneuvering and specific fishing techniques.

Speed and Power: Outboard motors are designed for higher speeds and are available in a wide range of horsepower options, while trolling motors are focused on providing controlled, quiet movement at lower speeds.

Mounting Location: Outboard motors are mounted on the transom, while trolling motors can be mounted on the bow and stern of the boat.

Outboard motors are essential for powering the boat at higher speeds and are the primary means of propulsion, while trolling motors are used for precise maneuvering and controlled movement, particularly in fishing scenarios that require slow and quiet operation.

Both types of motors play distinct but important roles in the overall functionality of a boat, catering to different aspects of boating and fishing activities.

Part 2: Types of Batteries for Electric Boat Motors

2.1 Deep Cycle VS Starting Batteries

Marine outboard motors and trolling motors typically use marine deep-cycle batteries. These deep-cycle batteries are designed to provide a steady amount of power over a longer period of time, making them well-suited for the demands of marine use, including starting the engine and powering onboard electronics.

Below are the differences between marine deep cycle and starting batteries:

1) Starting Batteries:

Starting batteries, also known as cranking batteries, are designed to provide a high burst of power for a short duration, typically to start an engine.

• High Cranking Amps (CA): These batteries can deliver a large amount of current quickly to start the boat's engine.
• Shallow Discharge: They are not designed for deep cycling (discharging to a low capacity), as frequent deep discharges can damage them.
• Construction: They have thinner plates compared to deep cycle batteries, optimized for quick bursts of energy rather than long-term use.
• Typical Use: Starting batteries are ideal for applications where the main demand is starting the engine, with minimal electrical load afterwards.

2) Deep Cycle Batteries:

Deep cycle batteries are designed to provide sustained power over an extended period, making them suitable for powering electric motors and onboard electronics in boats.

Characteristics of Deep Cycle Batteries:

• Deep Discharge Capability: These batteries can be discharged to a much lower capacity (often up to 50-80%) without damage, unlike starting batteries.
• Thicker Plates: Deep cycle batteries have thicker and more robust plates, allowing them to withstand frequent charging and discharging cycles.
• Capacity: They are rated in ampere-hours (Ah), indicating how much energy they can store and deliver over time.
• Typical Use: Deep cycle batteries are used in applications where sustained power over longer periods is required, such as trolling motors, electric propulsion systems, and powering onboard electronics.

How to Choose Between Starting and Deep Cycle

• Application Specificity: If your primary need is to start an engine and you have minimal additional electrical loads, a starting battery may suffice due to its high cranking amps and lower cost.
• Long-Term Power Needs: For electric boat motors and applications requiring sustained power over longer durations, deep cycle batteries are more appropriate due to their ability to handle repeated deep discharges without significant degradation.

2.2 Why Lithium Deep Cycle Electric Boat Batteries Better Choice

Lithium deep cycle batteries are generally considered a better choice than lead-acid batteries for electric boat applications for several reasons:

1. Energy Density and Weight

• Lithium: Higher energy density, meaning more energy can be stored in a smaller and lighter package. This is particularly important for boats where weight and space are critical.
• Lead Acid: Lower energy density, resulting in heavier and bulkier batteries for the same amount of stored energy.

2. Efficiency

• Lithium: More efficient, with charge/discharge efficiencies typically around 95-98%. This means more of the energy put into the battery is available for use.
• Lead Acid: Less efficient, with efficiencies around 70-85%. More energy is lost as heat during charging and discharging.

3. Depth of Discharge (DOD)

• Lithium: Can safely discharge up to 80-100% of their capacity without significantly shortening their lifespan.
• Lead Acid: Typically limited to 50% discharge to maintain a reasonable lifespan, meaning you need more capacity to achieve the same usable energy.

4. Cycle Life

• Lithium: Much longer cycle life, often 2,000 to 5,000 cycles at 80% DoD. High quality deep cycle lithium batteries like LiTime has the lifecycle 4000+ cycles at 100% DOD, which can be used for more than 10 years.
• Lead Acid: Shorter cycle life, typically 500-1,000 cycles at 50% DoD.

5. Maintenance

• Lithium: Virtually maintenance-free. They do not require regular water topping and have no issues with sulfation.
• Lead Acid: Require regular maintenance, including checking water levels and ensuring the terminals are clean. Sulfation can occur if they are not fully charged regularly.

6. Charge Rate

• Lithium: Can be charged at a much faster rate, which means less downtime waiting for the batteries to recharge.
• Lead Acid: Slower charging rates due to limitations in the chemistry.

7. Environmental Impact

• Lithium: Generally have a lower environmental impact over their lifecycle. While the mining and processing of lithium have environmental concerns, the longer lifespan and higher efficiency result in less frequent replacements and lower overall environmental footprint.
• Lead Acid: Higher environmental impact due to the toxicity of lead and sulfuric acid, and the need for more frequent replacements.

8. Voltage Stability

• Lithium: Provide more stable voltage output throughout the discharge cycle, ensuring consistent performance. Related reading: Full Guide of Battery Voltage
• Lead Acid: Voltage drops more significantly as the battery discharges, which can affect the performance of electrical systems.

9. Safety

• Lithium: Modern lithium batteries (especially Lithium Iron Phosphate, LiFePO4) are designed with safety features to prevent issues like thermal runaway and are generally considered safe.
• Lead Acid: Can release hydrogen gas during charging, which poses a risk of explosion if not properly vented. They also contain sulfuric acid, which is corrosive.

Part 3: Lithium Outboard Motor & Trolling Motor Batteries Recommend

LiTime provides deep cycle lithium batteries for marine. We offer lithium trolling motor and outboard motor batteries designed specifically for the unique demands of marine environments. 

3.1  Lithium Battery for Trolling Motor

LiTime 12V 100Ah TM is one of the most popular lithium batteries in trolling motor scenario.

featuring:

• Innovative moisture-proof design
• Salt-spray resistance for heightened durability
• Advanced low-temperature cutoff protection for safe charging

The battery is well received by the customers, now it has the upgraded model with bluetooth functon.

Designed for fishing enthusiasts, this innovative upgrade allows users to conveniently monitor their battery status from their phone. It eliminates guesswork with seamless, real-time updates, ensuring users stay powered up and focused on their fishing expeditions.

3.2  Lithium Battery for Electric Outboard Motor

The 12V 100Ah Lithium Electric Outboard Motor Battery is tailored for boaters seeking reliable and high-performance power for their 24V-60V electric outboard motors. For higher voltgae system, 36V 100ah outboard motor battery is a bettery chooice. Here are its standout features:

• Smart Bluetooth 5.0: Automatically connects to your phone for intelligent control of discharging, real-time monitoring of battery status and data, and effortless system checks.
• Max. 5S5P Configuration: Capable of building a powerful 60V 500Ah battery system (up to 32kWh of energy) with a continuous discharge current of up to 500A.
• High Performance BMS: Supports continuous charging/discharging at 100A, with peak performance reaching 500A for up to 1 second.

3.3 Why Choose LiTime for Your Marine Battery Needs?

At LiTime, we are dedicated to providing high-quality, reliable, and efficient lithium batteries tailored for marine, RV, golf cart and other off-grid applications. Our products are designed to meet the rigorous demands of boating, ensuring you have the power you need, when you need it. 

Choose LiTime and experience the difference that cutting-edge lithium battery technology can make for your boating adventures. Visit LiTime Warranty Policy and reviews for more information.

Question: Can I Use Marine Trolling Motor Battery in Electric Outboard Motor?

Normally, it's not recommended to use a battery designed for a trolling motor in an electric outboard motor since the surge discharge current might not be sufficient. Outboard motors often require higher power for acceleration and sustained operation, which can lead to higher surge currents that trolling motor batteries may not handle well.

Even if the battery can technically power the motor, the performance might be suboptimal. You might experience reduced thrust, lower speeds, or shorter running times than expected.

If you’re planning to use an electric outboard motor, it’s best to invest in a battery specifically designed for such applications like LiTime Outboard Motor Batteries. These batteries are built to handle the high power requirements and ensure optimal performance and safety.