Trolling motors are essential for anglers looking to navigate their favorite fishing spots quietly and efficiently. To power these motors, you typically rely on 12-volt deep-cycle batteries. Often, however, you might find that a single battery doesn’t provide enough runtime or voltage for your needs. This is where connecting two batteries comes in. Understanding whether to wire them in series or parallel is crucial for maximizing your Trolling Motor Battery motor’s performance.

Understanding the Basics: Voltage and Amperage

Before diving into the wiring process, let’s clarify the key concepts:

• Voltage (V): Think of voltage as the electrical pressure pushing current through a circuit. A higher voltage means more power.
• Amperage (Ah): This measures the amount of electrical current a battery can deliver over time. A higher amperage rating translates to longer runtime.

Series Connection: Increasing Voltage

Connecting batteries in series involves linking the positive terminal of one battery to the negative terminal of the other. This configuration increases the overall voltage while maintaining the amperage of a single battery.

When to Use Series Connection:

• If your trolling motor requires 24 volts, connecting two 12-volt batteries in series is necessary.
• This setup is ideal when you need more power to drive a larger or more powerful trolling motor.

How to Connect in Series:

1. Safety First: Disconnect any existing connections to the batteries and ensure the trolling motor is turned off. Wear safety glasses and gloves.
2. Identify Terminals: Locate the positive (+) and negative (-) terminals on each battery.
3. Connect the Terminals: Connect a heavy-gauge wire (the same gauge as your trolling motor wires) from the positive terminal of the first battery to the negative terminal of the second battery.
4. Connect to Trolling Motor: Connect the positive terminal of the second battery to the positive terminal of your trolling motor. Connect the negative terminal of the first battery to the negative terminal of your trolling motor.
5. Double-Check: Ensure all connections are tight and secure.

Important Note: When connecting batteries in series, use identical batteries with the same voltage and amperage ratings. Mixing batteries with different specifications can lead to uneven charging and premature battery failure.

Parallel Connection: Increasing Amperage

Connecting batteries in parallel involves linking the positive terminals of both batteries together and the negative terminals together. This configuration increases the overall amperage while maintaining the voltage of a single battery.

When to Use Parallel Connection:

• If you need to extend the runtime of your 12-volt trolling motor, connecting two 12-volt batteries in parallel is the way to go.
• This setup is ideal for longer fishing trips or when you anticipate using your trolling motor for extended periods.

How to Connect in Parallel:

1. Safety First: As always, disconnect any existing connections and ensure the trolling motor is off. Wear safety glasses and gloves.
2. Identify Terminals: Locate the positive (+) and negative (-) terminals on each battery.
3. Connect Positive Terminals: Connect a heavy-gauge wire from the positive terminal of the first battery to the positive terminal of the second battery.
4. Connect Negative Terminals: Connect another heavy-gauge wire from the negative terminal of the first battery to the negative terminal of the second battery.
5. Connect to Trolling Motor: Connect the positive terminal of either battery to the positive terminal of your trolling motor. Connect the negative terminal of either battery to the negative terminal of your trolling motor.
6. Double-Check: Ensure all connections are tight and secure.

Important Note: Similar to series connections, use identical batteries with the same voltage and amperage ratings for optimal performance and longevity.

Choosing the Right Configuration

The decision to connect your trolling motor batteries in series or parallel depends on your specific needs and the requirements of your trolling motor.

• Series: If your trolling motor requires a higher voltage (e.g., 24V), series connection is mandatory.
• Parallel: If you need to increase the runtime of your 12V trolling motor, parallel connection is the preferred method.

Additional Tips:

• Use heavy-gauge wiring to minimize voltage drop and ensure efficient power delivery.
• Use marine-grade battery terminals and connectors for corrosion resistance.
• Regularly inspect your battery connections for tightness and corrosion.
• Charge both batteries at the same time, with a charger that is rated for the correct voltage, and type of batteries.
• Consider using a battery selector switch, this will allow you to switch between batteries, or combine them with ease.

By understanding the principles of series and parallel connections, you can effectively power your trolling motor and enjoy longer, more productive fishing trips. Always prioritize safety and use appropriate equipment to avoid electrical hazards.