Abyss On-Board Alternator Charger - 36V - The essential boat upgrade that allows you to charge your 36V trolling motor battery from your engine's alternator on the go! While underway, your alternator's excess power redistributes from your starting battery so you get an extra boost, and better battery life for your trolling motor. Charges 36V trolling motor batteries Utilizes engine's alternator power Smart on-demand charging technology Protects cranking battery, minimum 13.3V Ideal onboard boat battery charger system