Composite materials of melt-spun Mg90Ni10 and graphite: Microstructural changes during cyclic hydrogenation and the impact on gas and heat transport characteristics

It is of high technical importance to consider the loading and unloading dynamics of hydride-based hydrogen storage tanks, which are mainly influenced by the heat and gas transfer properties inside the reaction bed. In this regard, hydride-graphite composites offer improved heat transfer properties and higher volumetric storage capacities compared to commonly used powder beds. s contribution, we report on the cycle stability of densified hydride-graphite composites based on melt-spun Mg90Ni10. The results reveal superior heat conduction properties compared to loose Mg90Ni10 flakes. Furthermore, this work deals with the hydrogenation behavior of such composites and their evolution throughout cyclic hydrogenation. Cycles at different temperatures and hydrogen pressures were conducted. High gas permeability in radial direction and sufficient thermal conductivity in combination with a stable composite structure underline the potential of such composites for hydrogen storage applications with high un-/loading dynamics.