Development of polymer electrolyte membrane fuel cell stack for unmanned aerial vehicle

The polymer electrolyte membrane fuel cell (PEMFC) is one of the important candidate for unmanned aerial vehicle (UAV) propulsion system due to high efficiency, low operating temperature, negligible noise and vibration, quick start up, high specific energy density and providing long endurance. In this study, power requirements during take-off, cruise flight and manoeuvre were measured on ground test set up for brushless engine that has 12 V operational voltage and 32 A maximum current. These test results were used to calculate the maximum fuel cell operating voltage and current for a certain surface area of a PEM fuel cell. After all the number of bipolar plates, rib-channel geometry and graphite bipolar plate's thickness are determined for fuel cell operating voltage, current and dimensional limits. NafionTM115 membrane, SGL BC 10 carbon paper as a gas diffusion layer (GDL) are selected for membrane electrolyte assembly (MEA). The catalyst layer (CL) was ultrasonically sprayed over the GDL, having micro porous layer. Amount of the loaded catalyst was 0,5 mg Pt/cm2 for both anode and cathode. To have a MEA, membrane was sandwiched in between two electrodes.. The results of these studies show that validation between the CFD analyses and experiments are very crucial step. Furthermore sealing materials for fuel cell operating pressure and temperature are also important for PEMFC stack for UAV application.