In the current dominance of lithium batteries in the drone market, the release of this news gives rise to the feeling that “the day is not far off when drones will switch to advanced hydrogen fuel cells.” In fact, turning hydrogen fuel cell drones with large payload capacity from blueprints to reality still has a journey ahead.
Fuel cells (FC), short for Fuel Cell, are devices that directly convert chemical energy present in fuel and oxidizer into electrical energy. Fuel and air are introduced into the fuel cell, and electricity is magically produced. Although it looks like a battery with positive and negative poles and an electrolyte on the outside, it cannot “store” electricity but is a “power plant”.
Its notable features include:
- High energy conversion efficiency, with an electrical conversion efficiency of 45% to 60%, compared to 30% to 40% for thermal and nuclear power.
- Low harmful emissions; low emissions of harmful gases such as SO2, NO2, and low noise, significantly reducing CO2 emissions, and no mechanical vibration.
- Strong modularity; flexible in scale and installation locations.
Hydrogen fuel cells, as the name suggests, use hydrogen gas as fuel to provide electrical energy. The working principle of hydrogen fuel cells involves electrochemical reactions between hydrogen and oxygen, converting their chemical energy into electrical energy. Hydrogen fuel cells exhibit outstanding environmental efficiency, causing no pollution to the environment after use and achieving 50% efficiency during power generation, making them promising for unmanned equipment applications.
For example, when considering battery-powered small drones, the endurance time using lithium batteries usually does not exceed 30 minutes, while hydrogen fuel cell drones can reach close to 2 hours.
The interest in hydrogen fuel cells is twofold: on one hand, it stems from the anticipation of their broad prospects, and on the other hand, it is due to certain weaknesses in the mainstream lithium batteries currently used in the market, such as insufficient endurance. Ordinary small lithium battery drones can only inspect 1-3 transmission towers per mission, and frequent recharging or battery replacement increases labor costs. Additionally, lithium battery drones have poor tolerance to harsh environmental conditions, making them difficult to start in severe cold or high temperatures, further shortening their endurance.
Some experimental results of hydrogen fuel cells prove their superiority in endurance. Compared to lithium batteries, hydrogen fuel cell drones have higher energy density and calorific value, with endurance capabilities exceeding 5 hours. They can tolerate harsh environments such as extreme cold and high temperatures. Moreover, because they fly at low altitudes, hydrogen leaks are difficult to accumulate, making them safer. Currently, many flight records of electric drones have been created and broken by hydrogen fuel cell drones. Furthermore, hydrogen fuel cells can be “fast-charged” similar to refueling a car, injecting hydrogen fuel in just a few minutes. Lithium batteries have a “hard injury” in low temperatures, while hydrogen fuel cells are not very “sensitive” to temperature, working as long as there is hydrogen and oxidizer. Additionally, hydrogen gas is a clean energy source with no environmental pollution. These advantages make hydrogen fuel cells a focus of research and development in various countries in recent years, being applied in aviation, transportation, and other fields.
The emerging solid-state hydrogen storage technology in recent years brings new hope to the application of hydrogen fuel cells. Research has found that certain alloys can form metal hydrides with hydrogen gas at low temperatures, releasing hydrogen gas as the temperature rises. Using such alloys to make hydrogen storage materials, hydrogen gas can be stored without high pressure. This technology has been applied to the development of new batteries for automobiles.
Based on this technology, some countries have started developing new hydrogen fuel cell drones. In the future, with cost reduction, hydrogen fuel cells are expected to be widely used in the military. If the issues of battery weight and volume can be further addressed, hydrogen fuel cell drones can be widely used in short-distance transportation, advanced tactical reconnaissance, and other tasks.
Fuel cell drones represent the combination of new energy technology and aviation science and technology, pointing to the direction of future green aviation development. Currently, in the field of new energy for drones, the development momentum of lithium batteries is still strong. Industrial drones are mainly electric drones, and the biggest technical bottleneck is the severe lack of endurance time and range. However, with the advancement of hydrogen fuel cell technology and the reduction of its manufacturing, storage, transportation, and use costs, hydrogen fuel cells may eventually become one of the main power sources driving drone flight.
What is the mystery of fuel cell technology? From the era of firewood chopping to the coal era when electricity became the main power, then to the oil era and the era of new energy and renewable energy, it can be seen that the hydrogen-to-carbon ratio of energy has always been increasing. Humanity has always been making efforts towards hydrogenation and decarbonization, essentially in the process of pursuing higher energy conversion efficiency. From this perspective, hydrogen energy is the ultimate goal of humanity. It can be seen that the essence of the transition of human energy lies in the continuous reduction of emissions and pollution. The ultimate product of hydrogen energy is only water, and the entire process is zero-emission and pollution-free. Therefore, it is called the ultimate clean energy. On the other hand, the Earth’s self-digestive capacity for carbon emissions is limited, which is also the reason why we regard reaching the peak and achieving carbon neutrality as a basic national policy.
Hydrogen power can increase the endurance of drones by 5-10 times. Industrial drones can control flight within line of sight and can also be applied and controlled across cities through 5G or satellite communication technology. Under future working conditions with a network environment, applications and control of drones in different cities or even on the back of the Earth can be realized. With the application capabilities of super-long endurance and remote control, the application scenarios of drones are constantly emerging as if opening an imaginative skylight.
In response to the increasingly serious problems of energy shortages and environmental pollution, using fuel cells with advantages such as high power density and environmental friendliness to generate electricity has become an inevitable choice. With the development of electric/multi-electric aircraft, the application of fuel cell systems to high-altitude drones has received widespread attention at home and abroad. From the perspective of market applications, fuel cell drones are more suitable for sectors such as mining, agriculture, measurement and monitoring, safety and emergency services. Long-endurance drones are especially suitable for applications in areas such as border patrols, large-scale forest and water surface inspections, long-distance pipeline power inspections, anti-terrorism aerial relays, and other fields. Currently, hydrogen-powered drones have been widely used in various fields, including the Winter Olympics, national power grid line inspections, and offshore oil and gas facilities inspections, with good market response.
In summary, the hydrogen fuel cell drone industry, with its advantages of high energy density, long endurance, and high environmental adaptability, is expected to occupy a considerable market position in the future drone market, especially the industrial drone market.
