Reservoir Cathode for Electric Space Propulsion

We propose a reservoir cathode to improve performance in both ion and Hall-effect thrusters. We propose to adapt our existing reservoir cathode technology to this purpose. Reservoir cathodes are the only emission sources that are capable of providing the necessary current density (>5.0 A/cm2) and life (>100,000 hours) for next generation high-power thrusters. More powerful thrusters are needed for interplanetary and lunar missions, including earth escape and near-earth space maneuvers. Reservoir cathodes are able to provide sufficient new barium to the cathode surface to overcome the high barium removal rates in ion engines. We have many years' experience developing reservoir cathodes. The key challenge is the stresses exerted on the cathode tube due to differential expansion and large temperature excursions. These lead to fracturing and weld failure. Our innovation solves this problem. In Phase I, a prototype is built and tested. In Phase II, we optimize for specific ion engines.

Any current application requiring long life and high emission density would profit from this innovation. The biggest market now is the Department of Defense for radars and communications. Other commercial applications requiring high loading and life are new high-speed x-ray tomography systems, electron beam stimulated lasers, geosynchronous satellite downlinks.

For Mars and lunar missions and the upcoming Juno mission to Jupiter. Also, piloted interplanetary missions become feasible with sufficient cathode output and life. Reservoir cathodes are also needed in linear beam amplifiers (traveling wave tubes and klystrons, etc.) to increase output, life, bandwidth, and frequency. This would raise data rates of wireless space communications.

This is early/mid-stage (TRL 3) — the most realistic path in is NASA SBIR/STTR, which funds small businesses and research institutions to develop technology aligned with NASA's needs (equity-free, phased funding). Check whether a current SBIR/STTR solicitation topic overlaps with this project's technology area, or contact the project directly (above) to ask.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.