How Long Will a 50Ah Battery Run a 55lb Trolling Motor?

Table of Content

• Understanding Battery Capacity: What Does Ah Mean
• What Does 55lb Thrust Mean for Power Consumption?
• How Long Will a 50Ah Trolling Motor Battery Last?
• Is A 12V 50Ah Battery Enough for A Trolling Motor?
• Extended Runtime: Redodo 12V 100Ah Lithium Trolling Motor Battery
• What Size Battery Do I Need for a 55lb Trolling Motor?
• Can I Parallel Two 12V 50Ah Batteries to Make a 12V 100Ah Battery?

Understanding Battery Capacity: What Does Ah Mean

Battery capacity is usually measured in ampere-hours (Ah) and represents the amount of electric charge the battery can deliver over time. Simply put:

• A 50Ah battery can theoretically deliver 50 amps for 1 hour, 25 amps for 2 hours, and so on.
• The voltage (typically 12V for trolling motors) remains the same, but the current draw varies based on how fast and how heavily you run the motor.

What Does 55lb Thrust Mean for Power Consumption?

Many assume that more thrust means more power drain, but thrust (measured in pounds) only reflects how much force the trolling motor generates to move your boat. Power consumption depends on your motor speed setting and motor efficiency.

On average, a 55lb thrust trolling motor draws:

• ~10–15 amps at low speeds
• ~25–30 amps at medium speeds
• ~40–50 amps at full throttle

Additionally, environmental factors like water conditions, wind resistance, or strong currents can cause your motor to work harder and pull more amps than average. Always consider these variables when estimating how long your battery will last on the water.

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

How Long Will a 50Ah Trolling Motor Battery Last?

To estimate how long your 55lb thrust trolling motor will run, let’s take Redodo 12V 50Ah Trolling Motor Lithium Battery as an example. Specifically designed for trolling motors up to 70lb thrust, this battery offers a significantly lighter weight and longer runtime than traditional lead-acid batteries.

We can use the formula to calculate the estimated runtime:

Trolling Motor Runtime (hours) = Battery Capacity (Ah) / Motor Current Draw (A)

In this case, we use the average current draw of 30A at medium speeds, the calculation would be:

Runtime = 50Ah / 30A ≈ 1.67 hours

That means a 12V 50Ah lithium battery can run a 55lb thrust trolling motor for about 1.67 hours at a moderate speed setting.

Redodo 12V 50Ah lithium battery for trolling motor

Is A 12V 50Ah Battery Enough for A Trolling Motor?

Based on the above estimation, a 12V 50Ah battery is a practical choice for small boats, kayaks, and anglers who typically fish for a few hours at a time. If you use your trolling motor at low to moderate speeds and take breaks between usage, a 50Ah lithium battery can provide 2–5 hours of runtime, depending on conditions.

However, if you plan longer outings, fish in strong currents, or run your motor at higher speeds, 50Ah might feel limiting. In these cases, you may need to carry a backup lithium battery for trolling motor or consider upgrading to a higher-capacity option for peace of mind.

Extended Runtime: Redodo 12V 100Ah Lithium Trolling Motor Battery

For those who need extended runtime on the water, the Redodo 12V 100Ah Trolling Motor Battery is an excellent upgrade. With twice the capacity of a 50Ah battery, it can run a 55lb thrust trolling motor for about 4-6 hours at medium speed, and 8-10 hours at lower speed. It's ideal for full-day fishing trips, larger boats, or users who rely heavily on their trolling motor.

Key features:

• Grade-A LiFePO4 cells
• 1280Wh of high energy, 2 times of 12V 50Ah battery
• Compact group 31 battery size
• Weighs only 22.15 lbs, 60% lighter than AGM battery
• 100A BMS with low-temperature protection
• 400A surge discharge current in 1 second
• Perfect for trolling motors of 30-70lbs
• 5-hour fast charging at 0.2C

What Size Battery Do I Need for a 55lb Trolling Motor?

The ideal battery size for a 55lb thrust trolling motor depends on how long you want to be on the water and at what speed you typically operate:

For most anglers, a 100Ah lithium battery offers the best balance between weight, runtime, and performance. It provides enough capacity for a full day on the water, even at medium to high speeds, without the need to carry a backup.

If you're fishing for shorter periods or using the motor intermittently, a 12V 50Ah battery may be all you need, especially when using a lightweight and efficient lithium battery like Redodo's.

Explore Redodo Lithium Marine Batteries

Can I Parallel Two 12V 50Ah Batteries to Make a 12V 100Ah Battery?

Yes, absolutely. You can connect two pack of 12V 50Ah battery in parallel to create a system equivalent energy of 12V 100Ah, giving you longer runtime without changing your trolling motor setup.

This is a great option if you already own a 50Ah battery and want to purchase an extra 50Ah battery to extend your runtime without replacing it. Just make sure both batteries are of the same brand, age, and charge level for safe and efficient operation.

Related Reading: How to Connect Batteries in Series and Parallel?

Conclusion

For a 55lb thrust trolling motor, a 50Ah battery, especially lithium battery can last about 1.5 to 3 hours, depending on your speed setting and water conditions. It’s a suitable option for short outings or light use, offering a good balance of weight and portability.

However, for longer trips or more demanding conditions, you may need a higher-capacity battery, such as a 100Ah or consider connecting two 50Ah batteries in parallel to double the runtime.

Understanding your motor’s power draw and your typical usage will help you determine the best battery size for your needs. Choosing the right trolling motor battery ensures a smoother, worry-free experience on the water and helps you make the most of your time outdoors.

Read More:

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