Instrumentation and characterization of materials for hydrogen storage

In order to identify and follow the challenges in the use of materials with the capacity to absorb hydrogen for energy storage, many groups address a diversity of issues, where the need to study the properties of the material upon absorbing hydrogen is always present. Appropriate equipment and techniques are needed: besides the use of classical systems, many research groups identified recently the need to study in more detail the properties related to the macroscopic changes of volume of the hydride powder as hydrogen content is cycled. In this article, we present the equipment and techniques developed by our group: after the classical volumetric systems, we addressed the problem of volumetric changes by building a novel coaxial capacitive system. This system measures the volume and porosity of a small amount of free hydride powder as a function of hydrogen content, after applying a complex deconvolution algorithm on the primary AC electric measurements.