Intrigued by Li-Ion endurance performance, I decided to try them on a little Multiplex Fox.

At first, I tried with 1S Li-Ion battery with a step up converter to reach ~7V to power up the whole system properly. I had to limit the motor range since the converter couldn't handle many amps (~2 A). This was insufficient and flight was hardly maintained. Switching to a 2S battery pack was the way to go.