Description: pH Matter will design and demonstrate the reversible fuel cell technology in a full-scale 2-kW electrolysis (1-kW fuel cell) breadboard prototype system, increasing the technology from TRL 3 to TRL 4 or greater for lunar surface applications. Reversible fuel cells (RFC) can store energy at 5 times higher energy density, but traditional systems require multiple components that are prone to failure. Additionally, in situ resource utilization (ISRU) will be needed to generate propellants and oxygen for life support. Electrolysis can be used to generate hydrogen and oxygen from locally sourced water. pH Matter is developing a highly integrated and novel “unitized” reversible fuel cell (URFC) system that enables more reliable long-duration energy storage, higher energy density, and increased functionality. pH Matter is developing a highly integrated and novel “unitized" reversible fuel cell (URFC) system that enables more reliable long-duration energy storage, higher energy density, and increased functionality. A single stack of unitized cells electrolyzes water to form hydrogen and oxygen and operates as a fuel cell to generate energy from stored hydrogen and oxygen. The unique cell design enables higher reliability through process intensification and elimination of recycle blowers and compressors. Furthermore, higher energy density and functionality will be possible with utilization of locally sourced water, reducing launch mass. During the Bi-furcated Reversible Alkaline Cell for Energy Storage – Tipping Point (BRACES-TP) Project lifecycle, pH Matter and its partners – Power to Hydrogen, NASA GRC, and Bettergy, will develop a URFC system from Technology Readiness Level (TRL) 3 to TRL> 4 for lunar surface applications.

Benefits: The BRACES-TP project will provide significant benefits compared to existing approaches for regenerative or reversible fuel cells. The advantage of pH Matter’s proposed approach is that the fuel cell and electrolysis functions will be performed by a single unit and will require only half of the fluid systems to manage compared to a discrete system with two electrochemical stacks (e.g., one pump versus multiple pumps / blowers, fewer pressure regulators, etc.). This component count reduction has the potential to improve system reliability and specific energy. This technology will support NASA's mission to establish a human presence on the moon and will allow for conversion of in situ derived water (extracted or byproduct) into ixygen and hydogren and be used as potential energy storage. The gases will be used for energy storage and propellants, with oxygen will be used for life support. Fuel cell reactants provide keep alive and operational power during sunlight eclipse periods.