Fuel cell systems in high power ranges generally use liquid cooling. However, when it comes to alternative propulsion systems for aviation, minimising weight is crucial. ZBT and its project partners are therefore jointly developing a fuel cell system with air cooling for unmanned aerial vehicles (UAVs, drones) and aircraft with a take-off weight of between 25 kilograms and two tonnes.
The aim of the BeHyPSy project is to develop, integrate and test an innovative drive system in a relevant performance range that is based on hydrogen as an energy carrier. The drive system will be integrated into a laboratory prototype, characterised in the overall system and validated in an aircraft. The aim is to show that the scaled system architecture can also be used at higher take-off weights, which will open up an important market.
In contrast to conventional fuel cell systems in the high power range (>50kW), the system developed here does not use liquid cooling, which significantly reduces weight and volume. This means that the air management of the fuel cell system is of central importance, as both the reactant supply and the cooling air supply must be adapted to the system.
Another important feature of the desired system architecture is the multiphase electric motor to increase reliability and availability. Each phase of the electric motor is supplied with power by a multi-stack fuel cell system.
The aim of ZBT's work is ‘lightweight fuel cell development for aviation applications’ in order to fulfil this system concept with the development of particularly lightweight, air-cooled fuel cell stacks.
The most important approaches to increasing the power density are
- the use of thin, formed metal foils for the bipolar plate compared to the composite bipolar plates primarily used in air-cooled fuel cell stacks,
- increasing the area utilisation at cell level through particularly compact cell designs and seal integration,
- the development of lightweight bracing
- and an increased degree of integration.
If these measures succeed in reducing the stack weight, the potential of the system architecture can be fully utilised.
Partners:
- ZAL - Zentrum für angewandte Luftfahrtforschung
- BREEZER Aircraft
- HAW - Hochschule für angewandte Wissenschaften Hamburg
- HSU - Helmut-Schmidt-Universität Hamburg
- RST - Rostock System-Technik
- ZBT - Zentrum für BrennstoffzellenTechnik
LUFO No.: 20M2249
Approval period: 1 May 2024 - 31 July 2027
