Static Feed Electrolyzer Technology Advancement for Space Application

The Static Feed Electrolyzer (SFE) is being developed by the National Aeronautics and Space Administration (NASA) through Life Systems, Inc. (Life Systems) as part of NASA's effort to mature water electrolysis technology for application in the Space Station Environmental Control/Life Support System (ECLSS), Propulsion and Reboost System, Extravehicular Activity (EVA) and Electric Power System (EPS). The water electrolysis process generates metabolic oxygen (O₂) for the crew cabin, EVA backpacks and air lock, and provides reactants for carbon dioxide (CO₂) removal, CO₂ reduction, propulsion/reboost systems and fuel cell electric power generation. The use within all of these applications will make water electrolysis a fundamental utilitylike technology for the Space Station. The most recent developments of the SFE technology and their applicability to Space Station systems along with the influences of Space Station design on the development of water electrolysis technology are discussed.

The NASA has selected to use water electrolysis aboard the Space Station to provide the O₂ and hydrogen, (H₂) for use in the ECLSS and the Propulsion System. Other applications of electrolysis technology in space are energy storage using a Regenerative Fuel Cell System (RFCS) and O₂ bottle recharging for EVA application. This paper discusses the design issues of electrolyzers for these applications and their relevance to the overall optimization of the electrolyzer. Also presented in this paper are results of recent developments of Life Systems' alkaline SFE.