Friday, November 12

'Hydrogen Storage Materials and Measurements'

Gregory P. Meisner

Materials and Processes Lab, GM Research & Development Center

Abstract: Current research on practical hydrogen storage, particularly for use by the automotive industry, is focused on finding new materials that satisfy the requirements of large gravimetric and volumetric hydrogen densities simultaneously with fast desorption and re-absorption kinetics at practical temperatures and pressures. Accurate measurements of hydrogen storage, however, are not trivial and are very prone to error. Typically, either volumetric or gravimetric techniques are used, but these and other techniques for measuring hydrogen sorption must be performed and interpreted with great care due to difficulties associated with small sample sizes, high gas pressures, very reactive materials, contamination, low signal-to-noise, poor experimental design, and in some cases, just bad science. Our results for the amount of hydrogen gas sorbed, weight change, and phase content are based on consistent and reproducible measurements using a combination of volumetric, gravimetric, and in-situ x-ray diffraction experiments. Finally, I will discuss some of the new classes of materials we are investigating for practical hydrogen storage.