Unmanned aerial vehicle (UAV) fuel cells, with their high energy density and potential for extended endurance, are gradually emerging as an alternative to traditional lithium-ion batteries. They demonstrate unique advantages in areas such as long-range logistics, high-altitude reconnaissance, and emergency rescue. However, due to current technological limitations, the actual endurance of fuel cell-powered UAVs still struggles to meet the demands of extreme missions. To significantly enhance their endurance, breakthroughs must be achieved through a multi-dimensional synergy in energy system efficiency, fuel storage technology, powertrain optimization, and environmental adaptability. 

Energy conversion efficiency is the foundation for extending endurance. Fuel cells generate electricity directly through the electrochemical reaction of hydrogen and oxygen, with a theoretical efficiency of over 60%. However, in practical operation, factors such as polarization losses, catalyst deactivation, and gas transport resistance often result in efficiencies below 50%. Optimizing the membrane electrode assembly (MEA) is key—using platinum alloy catalysts can reduce the amount of precious metals while improving resistance to poisoning, and developing thinner proton exchange membranes can reduce ionic conduction resistance, thereby effectively minimizing energy losses. Additionally, fuel cells respond more slowly than lithium batteries under dynamic operating conditions. 

Therefore, it is necessary to introduce an intelligent power management system that dynamically adjusts the power distribution between the fuel cell and an auxiliary energy storage battery based on flight requirements. During cruising phases, the fuel cell can be prioritized for stable power supply, while during instantaneous high-load scenarios such as takeoff, climbing, and obstacle avoidance, the lithium battery can quickly provide supplemental power. This forms a “fuel cell-based primary + lithium battery-based secondary” hybrid power architecture, balancing efficiency with dynamic response performance. Fuel storage technology directly determines the total amount of energy that can be carried onboard. The endurance bottleneck of hydrogen fuel cell UAVs often stems from the low density of hydrogen—even when using high-pressure gaseous storage at 35–70 MPa, its volumetric energy density remains limited. Solid-state hydrogen storage materials (such as magnesium-based alloys and metal-organic frameworks, MOFs) achieve higher-density storage at ambient temperature and pressure through chemical adsorption of hydrogen molecules, but issues related to cycle life and hydrogen release kinetics remain to be resolved. Liquid organic hydrogen carriers (such as N-ethylcarbazole) store hydrogen via reversible hydrogenation-dehydrogenation reactions; if future breakthroughs can address catalyst costs and reaction efficiency limitations, they may become an ideal option for long-endurance UAVs. For methanol fuel cells, directly improving fuel purity and optimizing the miniaturization of the hydrogen reforming module can also indirectly increase effective energy supply. 

Environmental adaptability and system lightweighting are equally critical. In low-temperature environments, the conductivity of the fuel cell’s proton exchange membrane decreases, necessitating the integration of micro-heating modules to preheat the reactant gases. Under high-temperature operating conditions, optimizing the heat dissipation structure is essential to prevent overheating of the fuel cell stack. Furthermore, reducing the overall weight of the UAV (e.g., by using carbon fiber composite materials) and streamlining auxiliary systems (such as integrating the air compressor and hydrogen recirculation pump into a single unit) can free up more space for the fuel cell and battery systems, indirectly extending endurance. 

In summary, enhancing the endurance of UAV fuel cells relies not on the breakthrough of a single technology, but on a systems engineering approach that deeply integrates material science, thermal management engineering, and intelligent control strategies. As solid-state hydrogen storage, efficient membrane electrodes, and hybrid power architectures continue to mature, UAVs are expected to achieve “cross-day” and “cross-region” ultra-long endurance in the future, opening up broader application scenarios for the low-altitude economy.