"The system has 150 – 250W input power, and consists of Hall thruster ST-25; Xenon storage and feed system (XFS) and Power processing unit (PPU)**."
https://sets.space/electric-propulsion-system-sps-25-with-hall-thruster/
"By splitting water by electrolysis and creating hydrogen/oxygen gas"
"Hydrogen and Oxygen gas spilt from water, we can "Hydroxy gas""
"Hydroxy gas can NOT be stored this way, it is too powerful to store in a tank."
http://waterpoweredcar.com/
"MPD thrusters using noncondensable hydrogen propellant will eliminate these concerns and provide higher exhaust velocities than lithium-fueled thrusters. Glenn is currently developing high-specific-impulse, megawatt-class, hydrogen-fueled MPD thruster technology. Research at Glenn encompasses a combination of systems analysis, numerical modeling, and high-power experiments that investigate pulsed versions of both self-field and applied-field MPD thrusters. Testing for these thrusters has demonstrated exhaust velocities of 100,000 meters per second (over 200,000 mph) and thrust levels of 100 Newtons (22.5 pounds) at power levels of 1 megawatt"
https://www.nasa.gov/centers/glenn/about/fs22grc.html