Oxygen Production from Mars Atmosphere Carbon Dioxide Using Solid Oxide Electrolysis

The Mars 2020 mission will include MOXIE, the Mars Oxygen ISRU Experiment aboard a Curiosity-class Mars rover. This first non-terrestrial ISRU experiment will demonstrate the initial feasibility of solid oxide electrolysis of Martian atmosphere CO2 as a means of producing oxygen for propellant oxidant in a Mars Ascent Vehicle (MAV). Ceramatec is developing the solid oxide electrolysis cell (SOEC, aka SOXE) stack for MOXIE. The rover host platform for the MOXIE project imposes severe constraints on mass, volume, peak power and total cycle energy, but it offers an early opportunity to demonstrate non-terrestrial ISRU with only the incremental cost of developing and delivering the 15kg MOXIE system on a 1000kg rover. Additional challenges arise in an unmanned operational environment, with once daily uplink and downlink schedules making man in the loop operation infeasible. Therefore, care must be taken to define a safe operating envelope in such a way that the system can be reliably operated without damaging itself as there is no option for a service call.