May 26, 2026
Imagine eagerly preparing for a day of fishing, only to discover your trolling motor has failed due to voltage issues. Many anglers face this dilemma: Can you connect a 12V motor directly to two 12V batteries wired in series for 24V power? The answer is emphatically no.
Connecting a 12V device to a 24V power source is essentially playing with fire. The excessive voltage can instantly breach the motor's insulation layer, causing short circuits that may destroy the motor or create safety hazards. This is equivalent to loading 200 pounds onto a bridge designed for 100 pounds – catastrophic failure is inevitable.
The proper method for utilizing two 12V batteries lies in understanding parallel versus series connections. Experts recommend parallel wiring – connecting positive terminals together and negative terminals together. This maintains 12V output while doubling the current capacity (measured in amp-hours, AH). For example, two 100AH 12V batteries in parallel yield 200AH capacity at 12V, providing extended runtime without voltage risks.
Marine electronics like Garmin units should never share batteries with trolling motors. The motor generates electromagnetic interference that can disrupt sensitive electronics, potentially causing malfunctions or damage. Dedicated battery systems ensure reliable operation for both propulsion and navigation equipment.
Some anglers propose using 24V for devices like Livescope black boxes while tapping one battery's 12V for the motor. This creates imbalanced discharge rates that degrade battery life. Picture two horses pulling a carriage where one works harder than the other – the system inevitably fails.
The safest approach combines parallel-connected 12V batteries for propulsion with separate power sources for electronics. This configuration maximizes battery longevity while ensuring stable operation of all equipment during fishing trips.
Beyond voltage considerations, proper battery maintenance is crucial:
Safety must always precede fishing enjoyment. Understanding proper battery configuration prevents equipment failures that could ruin your day on the water. Before your next trip, verify all electrical connections – a simple voltage check could save your fishing adventure.