Best Lithium Battery Sizes for Trolling Motors: A Comprehensive Guide
Introduction
Trolling motors are a must-have for anglers and boaters who need quiet, precise control on the water. Whether you’re fishing in a kayak or navigating a larger boat, the battery powering your trolling motor is the heart of your setup. Choosing the best lithium battery for trolling motor use can make all the difference in performance, weight, and longevity. Lithium batteries, particularly Lithium Iron Phosphate (LiFePO4), have become the go-to choice due to their lightweight design, extended lifespan, and ability to deliver consistent power. In this guide, we’ll dive into the ideal lithium battery sizes for 12V, 24V, and 36V trolling motors, including a detailed table, and cover everything you need to know to make an informed decision.
Why Choose Lithium Batteries for Trolling Motors?
Lithium batteries for trolling motors offer significant advantages over traditional lead-acid batteries, making them a top choice for modern boaters:
- Lightweight Design: A 12V 100Ah lithium battery for trolling motor weighs about 20–25 lbs, compared to 60–70 lbs for a lead-acid equivalent, which is especially beneficial for kayak trolling motor battery setups.
- Longer Lifespan: LiFePO4 batteries can last 4,000–15,000 cycles, compared to 300–500 cycles for lead-acid batteries, reducing replacement costs.
- Full Discharge Capability: Unlike lead-acid batteries, which should not be discharged below 50%, lithium batteries can be fully discharged without damage, maximizing usable capacity.
- Consistent Power Output: Lithium batteries maintain steady voltage throughout their discharge cycle, ensuring your trolling motor performs reliably.
- Faster Charging: They charge up to five times faster than lead-acid batteries, allowing you to get back on the water sooner.
- Low Maintenance: Lithium batteries require minimal upkeep and are resistant to vibration and harsh marine conditions.
These benefits make lithium batteries, such as the best 12V 100Ah lithium battery for trolling motor, an excellent investment for both casual and serious anglers.
Understanding Trolling Motor Voltage Requirements
Trolling motors typically operate at one of three voltages: 12V, 24V, or 36V. The voltage you need depends on your motor’s specifications and the size of your boat:
- 12V Trolling Motors: These are common for smaller boats or kayaks with thrust ratings up to 55 lbs. They require a single 12V battery, making them cost-effective and simple to set up.
- 24V Trolling Motors: Used for medium-sized boats with thrust ratings between 55 and 80 lbs, these require either a single 24V trolling motor battery or two 12V batteries connected in series to achieve 24V.
- 36V Trolling Motors: Designed for larger boats with thrust ratings above 80 lbs, these need a 36V trolling motor battery or three 12V batteries in series to provide 36V.
Matching the battery voltage to your motor is critical to avoid performance issues or damage. Always check your motor’s manual for specific voltage requirements.
How to Determine the Right Battery Capacity
Battery capacity, measured in amp-hours (Ah), determines how long your trolling motor can run before needing a recharge. To choose the right capacity, consider:
- Amp Draw: The current your motor draws depends on its thrust and speed setting. For example, a 12V 55-lb thrust motor may draw up to 50 amps at full speed but only 20–25 amps at medium speed.
- Desired Runtime: Decide how many hours you need the motor to run per trip. A typical fishing day might require 6–8 hours of runtime.
- Usage Conditions: Wind, waves, and current can increase power demands, requiring a larger capacity battery for consistent performance.
The formula for calculating runtime is:
Runtime (hours) = Battery Capacity (Ah) ÷ Average Amp Draw (A)
For example, a 12V 100Ah lithium battery for trolling motor with a motor drawing 20 amps on average provides approximately 5 hours of runtime (100 ÷ 20 = 5). Since lithium batteries can be discharged to 100%, you can use the full capacity, unlike lead-acid batteries, which require doubling the capacity to account for the 50% discharge limit.
What Size Lithium Battery Is Best For A Trolling Motor?
Based on industry standards and manufacturer recommendations, the following table provides guidance on the best lithium battery sizes for different trolling motor voltages and thrust ranges:
| Voltage | Thrust Range (lbs) | Recommended Battery | Notes |
|---|---|---|---|
| 12V | 20–30 | 12V 50Ah | Ideal for light use, small boats, or kayak trolling motor battery setups. Provides 4–6 hours of runtime at moderate speeds. |
| 12V | 30–55 | 12V 100Ah | The best 12V 100Ah lithium battery for trolling motor for most 12V motors, offering 6–8 hours of runtime. |
| 24V | 55–80 | 24V 100Ah or two 12V 100Ah in series | A 24 volt lithium battery for trolling motor suitable for medium-sized boats, providing ample power for extended trips. |
| 36V | >80 | 36V 100Ah or three 12V 100Ah in series | A 36 volt lithium trolling motor battery for large boats or high-thrust motors, ensuring reliable performance. |
These recommendations are based on typical usage patterns, where motors are not run at maximum speed continuously. For heavy usage or challenging conditions (e.g., strong currents), consider increasing the capacity (e.g., 12V 140Ah or 36V 100Ah) for longer runtime.
Additional Considerations for Choosing a Lithium Battery
When selecting a lithium battery for your trolling motor, keep these factors in mind:
- Weight and Size: Ensure the battery fits your boat’s compartment and doesn’t exceed weight limits, especially for kayaks. For example, a 12V 100Ah lithium battery weighs about 20–25 lbs, making it ideal for kayak trolling motor battery applications.
- Battery Management System (BMS): A quality lithium battery should have a built-in BMS to protect against overcharging, over-discharging, and short circuits, ensuring safety and longevity.
- Cost: While lithium batteries have a higher upfront cost (e.g., $300–$700 for a 24V trolling motor battery), their extended lifespan and efficiency make them cost-effective over time.
- Charging: Use a charger designed for LiFePO4 batteries to maintain optimal performance. Some batteries, like those from LiTime, include low-temperature charging protection for cold-weather use.
- Warranty and Durability: Look for batteries with strong warranties (e.g., 5 years) and resistance to marine conditions, such as vibration and corrosion.
- Compatibility: Verify that the battery’s continuous discharge rate meets or exceeds your motor’s maximum amp draw to prevent performance issues.
Conclusion
Selecting the right lithium battery size for your trolling motor ensures you get the most out of your boating experience. For 12V motors, a 12V 100Ah lithium battery for trolling motor is a versatile choice, while 24 volt trolling motor battery and 36 volt trolling motor battery options (or equivalent series connections) are ideal for higher-thrust motors. By considering your motor’s voltage, amp draw, and desired runtime, you can choose a battery that balances performance, weight, and cost. Always consult your trolling motor’s manual and battery manufacturer guidelines to ensure compatibility and optimal performance.