UK-based Perpetual Atomics and US QSA Global have turned americium dioxide into stable, large-scale pellets using an industrially scalable process suitable for direct use in the production of sealed sources for radioisotope power systems.
Perpetual Atomics, spun out from the University of Leicester and based at the university’s Space Park Leicester and QSA Global have processed americium into sealed sources for radioisotope power systems, including radioisotope heater units (RHUs) and radioisotope thermoelectric generators (RTGs).
The team have produced the largest reported ceramic americium pellet of this type using a new method not previously applied to americium. Robust americium pellets can be directly integrated into sealed power-systems using an industrially scalable method. This development helps unlock reliable, long-duration power for future space missions.
The new approach is rapid, minimises pellet volume and waste, and maximises throughput, enabling the production of larger-scale pellets tailored to the needs of future power systems.
Dr Ramy Mesalam, Perpetual Atomics, Chief Technical Officer, commented: “We are very excited about this development as it underscores the importance of the fundamental science and engineering required to develop new technologies, as well as the empirical nature of the challenge. Developing the fuel form and a stable processing method was the primary challenge and this was successfully addressed first with surrogates and then translated to americium in collaboration with the QSA team in record time.”
Dr Joe Lapinskas, Director of Innovation and Marketing at QSA Global, noted: “In just one year of working together, Perpetual Atomics and QSA Global have gone from concept to manufacturable fuel pellets. By combining Perpetual Atomics’ space nuclear power expertise with QSA Global’s decades of sealed source design, qualification, and high-reliability manufacturing, we’re turning a promising concept into real hardware ready to power the next generation of demanding space missions.”
Matthew Cook, Head of Space Exploration at the UK Space Agency, said: “This is an exciting breakthrough that demonstrates the UK’s growing leadership in space nuclear power systems. The work by Perpetual Atomics and QSA Global, shows how international collaboration can accelerate innovation and turn ambitious concepts into deployable technology at remarkable speed.”
Historically, plutonium-238 (Pu-238) has been the fuel of choice for space-based RHUs and RTGs. Americium-241, however, has become an attractive alternative to Pu-238, particularly in Europe, which does not have a large inventory of available plutonium. In addition, Am-241 has a half-life of around 430 years, compared with the 90-year half-life of Pu-238, making it more suitable for long-duration missions.
