Larry's site says it draws only 13 amps...if you have the model that I found.
Even a 30 lb trolling motor draws 30 amps. Assuming you only use the winch sporadically, I can't see why you'd need another battery for it.
I cannot foresee any situation where you'd have the trolling motor running, and the winch working, at the same time. If you did, you might have an issue.
richg99
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Welcome to the home of the “Water Wench” a rock-solid River Larry anchor system,
built for strength, with craftsmanship, and for ease of use.
This is the most reliable boat anchor system available.
• Pinpoint anchor placement can be achieved with ease.
• 10,000 hour continuous run 12-volt motor.
• Draws only 13 amps under full load.
• 3/8" diameter kern mantle rescue rope. (50 ft. max.)
• 8,000 lb. strength with 1.2% water absorption rate.
• Continuous run industrial gearbox with built in pressure relief valve.