Accelerated Materials Discovery for Sustainable Hydrogen Compression

The transition to net zero carbon emissions by 2050 requires an acceleration of advances in fundamental science that will have a pragmatic impact on critical technologies. The high level of research on hydrogen materials for hydrogen storage over the last decades has led to significant breakthroughs in fundamental science. Climate change now calls for a re-focus of the hydrogen material science to translate the properties of these materials toward superior and pragmatic solutions needed beyond just storage to across the hydrogen supply chains. Light transport decarbonization can be tackled through electrification, but hydrogen remains an option to decarbonize the hard-to-abate sectors such as heavy-duty transport, off road vehicles, marine and aerospace. However, implementing hydrogen as a clean energy vector has challenges in other related technologies such as compression, sensing, purification, storage and distribution of hydrogen. In this project, we focus on the challenges associated with hydrogen compression. Due to its low density, hydrogen compression is required along the entire supply chain from production to end use. A wide range of hydrogen compression technologies have been investigated, and the most common hydrogen compressors on the market are based on mechanical compression, such as reciprocating, diaphragm, linear, and ionic liquid compressors, which are costly to purchase upfront and consume high levels of electricity to run, typically requiring 20-30% of the calorific value of the hydrogen to compress hydrogen to high pressures to 700 bar and beyond. The operating cost of mechanical hydrogen compressors is high due to the requirements of constant and significant maintenance, particularly for valves, packing, and piston rings. The potential for an alternative technology such as metal hydride compressors is significant offering opportunities for compressing hydrogen using waste heat from electrolysers or other renewable sources (e.g. solar thermal) delivering high efficiency. Metal hydride compressors do not require moving parts in the compression process, and have, therefore, much lower operational cost and significantly enhanced reliability and safety. The vision of this joint UK-Japan project is to address challenges associated with one of the main bottlenecks of developing efficient metal-hydride hydrogen compressors, i.e. identifying the optimal metal hydride materials for hydrogen compression that can be used with sustainable heat. This will be accelerated by a combined experimental-computational approach as well as the combination of the research expertises and facilities on hydrogen storage materials of the University of Nottingham and the AIST Tsukuba supported by the ICMPE (Paris) and the Sandia National Laboratory. By this approach we will be able to identify optimal metal alloy compositions that can be utilised to compress hydrogen gas from 20~30 bar (produced by an electrolyser using renewable energy sources such as wind and solar) to high pressures, e.g. > 700 bar for hydrogen refuellers via multiple hydride combinations, or 80 bar for hydrogen pipelines via a single stage metal-hydride compressor. As experimental data is very limited and in parts very difficult to obtain, to accelerate the metal alloys discovery, we need to combine a wide range of experimental and computational techniques, including atomistic materials modelling, materials synthesis, and materials structure and hydrogen storage property characterisations using a one of a kind high pressure Sieverts apparatus. The best candidate metal alloys on hydrogen compression applications will be scaled up and tested in our in-house multi-stage prototype metal-hydride compressor device.