IE-FLIGHT 300 evaporatively cooled PEM hydrogen fuel cell system for eVTOL and regional aircraft

The IE-FLIGHT 300 is an evaporatively cooled PEM hydrogen fuel cell system for eVTOL and regional aircraft, made by Intelligent Energy. It belongs to the IE-FLIGHT product line, which provides zero-emission powertrains for aircraft serving sub-regional and regional markets for cargo and passengers. The system is suitable for CS-23 and CS-25 aircraft, eVTOL aircraft and auxiliary power unit applications, and the product line is also listed for heavy lift drones.

The system is built around Intelligent Energy's proprietary evaporatively cooled PEM fuel cell stack, Gen4, with metallic pressed plates. Rated net power output is 300 kW at sea level, and the rating derates as altitude increases, so integrators should size the powertrain against the altitude profile of the mission. Peak efficiency is 57%, reached at a low part-load point rather than at rated power. The datasheet also gives a hydrogen flow rate at rated power that rises from beginning of life to end of life, which matters when sizing the hydrogen supply for the full service life of the stack.

Gross current output is up to 600 A. Gross voltage is 600–1200 V: 600 V at maximum output at end of life, and up to 1200 V at no-load or open-circuit condition. Downstream power electronics and the DC bus must therefore tolerate the open-circuit voltage, not only the loaded voltage. The datasheet specifies separate low-voltage and high-voltage system inputs for the control and auxiliary loads of the fuel cell system.

Patented direct water injection cooling means no external humidification is required, which simplifies the balance of plant and supports reliability. The high-temperature architecture allows smaller heat exchangers, and the product uses an air-cooled condenser. Mass is 200 kg excluding the air-cooled condenser. Overall dimensions are given in the specifications for the product including the air-cooled condenser, as illustrated inside a fixed wing propulsion system concept. Environmental protection is IP67, where the air vehicle structure provides limited ingress protection. The fuel is gaseous hydrogen supplied at a regulated gauge pressure. The scope of supply covers the thermal, air, exhaust, hydrogen recirculation, high-voltage and low-voltage and control modules; hydrogen storage, powerplant control and airframe power distribution are outside it.

The IE-FLIGHT line is designed to be certifiable for aviation applications, with a certifiable architecture built around aerospace software and control. The datasheet does not list a specific certificate or standard approval for this model. The architecture is scalable for multi-MW fuel cell installations, so the same technology can serve larger aircraft.

Typical applications are sub-regional and regional aircraft, passenger and cargo eVTOL aircraft, advanced air mobility platforms, heavy lift drones and auxiliary power units. In each case the fuel cell supplies electrical power to electric motors that drive propellers, fans or rotors, with zero emissions at the point of use.