Scale Up and Coupling of the MOXIE Solid Oxide Electrolyzer for Mission-Scale Lunar and Martian Applications

The successful, repeated operation of MOXIE on the Mars Perseverance Rover has made In-Situ Resource Utilization (ISRU) a reality. Since developing the Solid OXide Electrolysis (SOXE) stacks for the Mars 2020 MOXIE program in 2017, the OxEon team has made significant advancements in both the scale and capabilities of the technology with the support of a NASA NextSTEP ISRU, SMTD Tipping Point, and SBIR award. Newer variants of the SOXE stack have a five-fold increase in cell area and a 6.5-fold increase in cells per stack, for a stack scaled 33-times the 0.5% scale of the device in MOXIE. Six of these OxEon mission-scale SOXE stacks will produce 30 tons of propellant oxygen to fuel a MAV in the 19-month window between landing an unfueled MAV pre-supply mission and the next launch opportunity for the first crewed Mars Mission, meeting target requirements for a return mission. The mission-scale SOXE stack utilizes an interconnect specially designed to allow for a sealed anode perimeter and internally manifolded collection of the 99.9%+ pure O2 produced during operation. Additionally, OxEon has investigated a combination of materials to improve redox tolerance of the nickel-based cathode and demonstrated this advancement in operational stability in scaled up stack systems. Demonstration systems have been built and tested with the mission-scale stacks, under relevant test conditions, for both Lunar and Martian applications. A breadboard system for the production of propellant H2 and O2 from Lunar ice will be tested in a cryo-vac chamber at JSC in 2023. A second, mission-scale stack demonstration system, for the production of O2 and CH4 from Martian H2O and atmospheric CO2, will be tested at JPL in December of 2022, before additional testing at JSC in 2023.