You will need a 50+ # thrust to navigate upwards on the Clinch on one generator. The issue will come when you start looking at 24v trolling motors; then you will need two-batteries.
If you are only using it to head upstream, a small gas motor might be a better option. For example I have a 3 hp Tanaka that weighs only 24 lbs. 3hp is roughly 200 lbs of thrust. A single deep-cycle marine battery is going to be 60+ lbs.