A multi-rotor aircraft with an energy source based on hydrogen fuel cells was presented by a scientific team of Russian developers from the NTI Competence Center for Technologies of New and Mobile Energy Sources of the Federal Research Center for Pharmaceutical Physics and the Moscow Chemical Industry of the Russian Academy of Sciences (Chernogolovka) and the Youth Laboratory of Advanced Energy of the Institute of Electric Propulsion of the Moscow Institute of Physics and Technology (Dolgoprudny) . A 2-4-fold advantage in the energy intensity of power plants based on fuel cells over lithium-ion batteries has been demonstrated. According to the test results, the continuous flight time was 2.5 hours.
The currently super-relevant sphere of application of hydrogen fuel is unmanned vehicles, and, first of all, aviation. It is there that the decisive factor is the operating time provided by the power supply.
The main advantage of power plants based on hydrogen fuel cells is the high specific energy intensity compared to batteries, which is ensured by the high efficiency of fuel cells. The achieved energy intensity values are 550-750 W*h/kg. This is 2-4 times higher than the energy intensity of modern batteries, which provides a proportional increase in the autonomy of unmanned vehicles.
An interuniversity collaboration of scientists from the FRC PCP and the MC RAS and the Moscow Institute of Physics and Technology has developed a pilot model of a multi-rotor aircraft with an energy source based on hydrogen fuel cells in the Arctic.
“The drone’s power source is two 1 kilowatt fuel cell batteries. The fuel for them is hydrogen in a high-pressure cylinder. Such a power plant can provide a continuous flight of the apparatus for up to 2.5 hours. If the same device is powered by lithium-ion batteries, then to ensure this flight time, it will have to be periodically planted, changed or charged batteries, or several devices should be launched simultaneously, which makes the process more costly. The design has a takeoff weight of up to 15 kg, can carry a payload of up to 2 kg, and a flight speed of up to 50 km/h,” said Alexei Levchenko, project manager, head of the Competence Center of the NTI FRC PCP and the MC RAS.
The developers emphasize that for light unmanned vehicles, the use of fuel cells with hydrogen as a fuel is currently quite justified. In addition, fuel cells created for a hydrogen aircraft can be used not only in aviation, but for solving a wide range of tasks – portable power supply, charging gadgets, for electric bicycles as an energy source, then they can be introduced even as part of small power plants. But so far, the main problem for the introduction of hydrogen technologies in our country can be considered the lack of refueling infrastructure.
“Our development has a number of obvious advantages: one of the main ones is the potential ability to work at negative temperatures. Fuel cells differ from other energy sources in absolute environmental safety, since only vapors of distilled water are emitted during operation, which can even be drunk,” added Dmitry Grebtsov, head of the youth laboratory.
The principle of operation of fuel cells has been known for more than 150 years, but only in recent decades have the characteristics of power plants based on them reached values that ensure competition with both internal combustion engines and batteries. This happened both by improving the characteristics of both the fuel cells themselves and related equipment, in particular high-pressure cylinders.
Modern fuel cells are superior to lithium-ion batteries in many respects, but they are quite difficult and expensive to manufacture, including due to the high cost of ion-exchange membranes.
The ion exchange membrane is one of the most important components of fuel cells. The technologies for its creation are strategically important for the domestic industry at the moment, in particular for the full cycle of creating domestic hydrogen power plants for transport and unmanned vehicles.
Young MIPT scientists are actively developing and planning to introduce into production in the near future a technology for creating proton-conducting membranes based on perfluorinated sulfocationic polymers suitable for the manufacture of modern hydrogen fuel cells.
