Fuel Cell Power Sources for Small Unmanned Aerial Vehicles

Protonex Technology Corporation will build a fuel cell based power system that enables the flight of long-duration small aircraft that are not feasible with batteries. Currently long-duration aircraft must be powered by small combustion engines which are loud and unreliable. We will use a new chemical hydride fueling technology gravimetrically attaining over 10% by weight deliverable hydrogen, which is equivalent to 3400 Whr/kg of fuel energy. When coupled with a 50% electrically efficient PEM fuel cell system, the combined electrical power source approaches 1700 Whr/kg. This is much higher than current state-of-the-art lithium batteries used in electrical UAVs which currently achieve 200 Whr/kg and are projected to top out around 300 Whr/kg in 5 years. The higher energy density of the fuel cell system in comparison with batteries will enable an aircraft to fly for significantly longer durations and carry more payload. An opportunity for fuel cells in small UAVs exists because fuel cell systems can attain higher specific energies than batteries, thus enabling electric UAV missions in the 10-100 hour range. They also are much quieter and have far better durability than ICEs.