How Long Does a Trolling Motor Battery Last?

When you're out on the water—whether fishing, exploring, or just simply cruising, knowing how long your battery will power your motor is crucial for planning a worry-free trip.

In this article, we'll guide you on how to estimate the running time for your trolling motor, and the key factors that affect trolling motor battery runtime to help you determine the right setup on the water.

The Key Factors of Trolling Motor Battery Runtime

The runtime of a trolling motor battery depends on three primary factors: Battery capacity, system voltage, and the trolling motor’s power draw.

1. Battery Capacity

The capacity of a battery is measured in amp hours (Ah), which represents how much energy the battery can deliver over time. For example: A 100Ah battery can deliver 100 amps for 1 hour or 10 amps for 10 hours.

Lithium LiFePO4 batteries, unlike traditional lead-acid batteries, offer 100% usable capacity. That is, a 100Ah lithium battery truly gives you 100Ah, whereas a lead-acid battery typically only allows 50% depth of discharge (usable Ah) before voltage drops too low.

2. System Voltage

Trolling motors typically operate at 12V, 24V, or 36V. Higher-voltage motors are more efficient and powerful, drawing less current for the same amount of work, which can extend runtime when paired with the right battery bank configuration.

Read More: Trolling Motor Battery System: 12V 24V 36V?

3. Power Draw of the Trolling Motor

Each trolling motor model has a rated current draw. The power draw of the trolling motor is the amount of energy it requires to run, usually measured in watts or amps.

Power draw increases with:

• Higher throttle levels (speed)
• Heavy loads (like multiple passengers or gear)
• Adverse water conditions (strong currents or wind)

For example, a 55-lbs thrust 12V trolling motor may draw:

• 5–10A at 30% throttle
• 40–50A at full throttle

Manufacturers often provide power draw estimates. Typical amp draws by motor thrust:

4. Other Electrical Loads Sharing the Battery

Electronics like fish finders, lights, GPS, bilge pumps, and live wells will also pull current from your battery. Every amp adds up. For extended runtime of your trolling motor, consider using a dedicated trolling motor battery to power it.

Calculating Trolling Motor Battery Runtime

Here’s a simple formula to estimate how long your battery will last for a trolling motor under certain conditions:

Battery Runtime (hours) = Battery Capacity (Ah) ÷ Motor's Amp Draw (A)

For example, a 12V 100Ah LiFePO4 battery can power a trolling motor with 20A of current draw at 50% throttle about 5 hours (100Ah÷20A).

However, the estimates assume ideal conditions. In real-world usage, it may be lower due to the boat weight, motor efficiency, wind, other electronics amps, etc.

According to MinnKota, to calculate approximate running time, the actual battery capacity may multiply by 85%:

Battery Amp Hour (Ah) Rating x 85% ÷ motor amp draw = approximate running time

Example:

120Ah x 85% = 102Ah

102Ah ÷ 30 amps = 3.4 hours

How Many Batteries Do My Trolling Motor Need?

The number of batteries your trolling motor needs depends on its voltage requirement and the motor’s thrust rating. The chart below can help you determine how many batteries and the voltage needed by thrust.

Take an example as Redodo 12V 100Ah lithium trolling motor battery:

Trolling Motor Battery Runtime Chart

Note: Series connection increases battery voltage, not amp-hours.

Trolling Motor Battery Recommendations

Looking to upgrade a lithium trolling motor battery or build a new system? Here are Redodo’s top options by system voltage:

12V Battery System for Motors up to 70 lbs Thrust

Redodo 12V 50Ah Bluetooth Trolling Motor Battery

• Weighs only 11.27 lbs, super compact and lightweight
• Ideal for trolling motor of small boat, fish finder, ice angling, and ham radio
• Low-temp cutoff protection in cold weather
• Upgraded BMS with 20+ protections for marine environments
• 4000+ deep cycles with EV-grade LiFePO4 cells
  
• Bluetooth 5.0 monitoring via app
  

Redodo 12V 100Ah Lithium Trolling Motor Battery

• Ideal for kayak and small boats under 70 lbs thrust
• Compact and lightweight (only 22.15 lbs)
• Tow-temp cutoff protection for safety
• Up to 4000+ deep cycles at 100% DOD
• 1280Wh energy capacity
• Longer runtime and 10+ years lifespan

24V Battery System for Motors up to 100 lbs Thrust

Redodo 24V 50Ah Bluetooth Trolling Motor Battery

• Perfect for 24V trolling motors up to 100 lbs thrust
• Bluetooth control and monitor battery status
• Weighs just 21.14 lbs, Group 24 battery size
• Advanced BMS with low-temp cutoff protection
• 4,000+ deep cycles for reliable, long-term performance
• Supports up to 4 series and 4 parallel for larger energy needs

36V Battery System for Motors up to 120 lbs Thrust

Redodo 36V 50Ah Lithium Trolling Motor Battery

• Ideal for 36V Trolling Motors with 100-120 lbs
• Group 31 battery dimensions, one pack replacement of 3*12V batteries
• Weighs 32.8 lbs, 70% lighter than three lead-acid options
• Low-temp charging protection
• Built-in 50A BMS with auto-recovery in 30 seconds
• Marine-grade protection from moisture and salt spray
• 4,000+ cycles with EV-grade prismatic cells

Tips for Choosing the Right Battery Configuration

• Always match your motor’s voltage rating, don’t run a 24V motor on 12V.
• Use lithium batteries for better performance, which are 100% depth of discharge, longer lifespan, lighter weight.
• If you’re using multiple batteries in series, make sure all are the same brand, type, voltage, BMS, and capacity.

Conclusion

Understanding how long a trolling motor battery lasts is essential for ensuring you have reliable power throughout your adventures. By learning how to calculate your system's power needs and choosing the right type of your motor’s demands, battery type, and usage patterns, you can extend the trolling motor runtime and enjoy more days out on the water.

Have any questions? Feel free to contact us by service@redodopower.com! Subscribe to our newsletter for more insights and tips on trolling motor battery and additional store discounts.

Read More:

How Fast Will a Kayak Go With a Trolling Motor?

Best Trolling Motor Battery: Types & Top Picks

How Long Will a 100Ah Battery Run a 55lb Trolling Motor?

What Size Battery for Trolling Motor [Type & Size]