Lowest Risk way to increase all-electric UAV flight times & range is Clean Fuel Cells as REXs (range extenders) to produce the required electric power – closest to reality of these 3 ways to increase flight times – https://protonex.com/…/keeping-drones-powered-3-near-future…. – Boeing subsidiary, Insitu, says it hopes to roll out a commercial, hydrogen fuel-cell version of its ScanEagle drone in 2017. Here are a few systems we are evaluating for client projects.
PEM Fuel Cell Technology
Proton exchange membrane (PEM) fuel cells operate at relatively low temperatures (<80ºC or <175ºF), offer quick start-up times, and require only hydrogen and oxygen to operate. Protonex’ patented design and manufacturing processes for PEM systems provide significant technical and cost advantages compared to competing solutions. Protonex fuel cell stacks utilize a unique mould-in-place seating approach that provides much greater repeatability and robustness in assembly and performance than traditional approaches. Our fuel cells are also driven by balance-of-plant subsystems based on commercially available, proven components and materials.
The Fuel Cell System
The core of a fuel cell system is the fuel cell stack. A Protonex fuel cell stack consists of two primary components: 1) the bipolar plate (cathode and anode), and 2) the membrane electrode assembly (MEA). A single cell of the fuel cell stack is created by stacking a cathode bipolar plate on top of a MEA on top of an anode bipolar plate as shown in Figure 1; this stack up is repeated as necessary to adjust the electrical output characteristics of the fuel cell. The MEA consists of two porous, catalyst-coated electrodes (cathode and anode) that are layered upon either side of an electrolytic membrane. The bipolar plates are electrically conductive and facilitate the supply of oxygen (cathode) and hydrogen (anode) to the MEA via integral flow passages.