Performance of a Minn Kota electric motor on an inflatable hull

As a summer project, I’m experimenting with adding an electric trolling motor on a 2.9 m inflatable. My medium term goal is to hook up a leftover Ardupilot and have the boat slowly take me around the lake in the most plesent way possible.

Everything is done on a budget so it’s a 34 lb thrust motor with a 20 Ah LiFePO4 battery. I did a run today in still conditions and used the power distribution board and GPS to measure the performance.

The motor has a tiller with 5 speed settings and you can see speeds 2 to 5 on the chart. I omitted speed 1 as the velocity had too much variance.

Speed 4 at 14 A looks like the sweet spot and gives ~1.5 hours of endurance and ~5.5 km of range.

Next up is to add a PWM speed controller and servo.