Precision Combustion, Inc. (PCI), in collaboration with a Research Institution, proposes to further mature a new fuel cell design utilizing a solid electrolyte technology that will meet NASAs target specifications of (i) cycling through very low temperatures (<150K) to survive storage during lunar night or cis-lunar travel; (ii) recovery of >98% of its mechanical, electrical, and chemical performance post cycling; (iii) capability to process propellants and tolerate standard propellant contaminants without performance loss; (iv) capability to sustain high pressures and vibration loads; and (v) achieving current density of >300 mA/cm2 (for >500 hrs), transient currents of >750 mA/cm2 for 30 seconds and slew rates of >50 A/cm2/s. The fuel cell consists of a solid electrolyte in an innovative design configuration and internal reforming catalysts, allowing fuel cell operation with propellants. The innovative cell design and integration of reforming elements demonstrated effective fuel cell operation with tolerance to extreme temperature swing, thermal cycling, and large differential pressure. A high-performing fuel cell design was successfully fabricated and optimized in Phase I, and its performance experimentally evaluated. Extreme thermal cycling capability to <150 K, with fast heat-up to its operational temperature was also demonstrated. At the end of Phase I, a clear path towards a Phase II prototype was described, where a breadboard hardware will be developed, demonstrated, and delivered to a NASA facility for demonstration testing. PCIs approach will result in a system that will be much smaller, lighter, and more thermally effective than current or prospective alternative technologies. This effort will be valuable to NASA as it will significantly reduce the known mission technical risks and increase mission capability/durability/extensibility while at the same time increasing the TRL of the fuel cells for lunar/Mars power generation and ISRU application. Potential NASA Applications (Limit 1500 characters, approximately 150 words) Potential NASA applications include future power generation systems from propellants and LOX initially for lunar bases and supporting upcoming Commercial Lunar Payload Services (CLPS). The systems have applicability over a broad range of mobile and stationary lunar surface systems, including landers, rovers, robotic rovers, and various science platforms. Key potential customers include NASAs Space Technology Mission Directorate (STMD), NASA Glenn Research Center, NASA Johnson Space Center, and private sector customers. Potential Non-NASA Applications (Limit 1500 characters, approximately 150 words) Non-NASA applications include automotive, defense, and distributed power generation opportunities which rely on fast start, vibration tolerance, and high efficiency. Also, SOFC-based military generators/vehicle APUs, commercial vehicle APUs and stationary fuel cell Combined Heat & Power (CHP) applications seeking a more cost-effective, lightweight, durable, and power dense fuel cell stack.