[1][2] The design for U-Battery was created at Delft University of Technology in the Netherlands and Manchester University in the United Kingdom basing it on high temperature reactor (HTR) technology which was already available in Europe.

[4] Finance has been supported by grants from the UK government's Advanced Modular Reactor Feasibility and Development project, being selected for phase two in July 2020.

[2] The target fuel is TRISO with 17–20% enriched uranium which might be supplemented by thorium with a beryllium oxide reflector.

[4] In March 2023, Urenco ended its support, saying "we can no longer continue our support of the U-Battery Advanced Modular Reactor project, having exhausted our attempts to secure the commitment of new commercial investors."

Intellectual property in the design will be transferred to the National Nuclear Laboratory.