Analysis of desorption behavior in metal-based hydrogen storage systems through pilot-scale experimentation and numerical simulation

Abstract

Hydrogen storage alloys that form metal hydrides (MH) are a promising type of material in hydrogen storage applications, allowing for low-pressure, high-density hydrogen storage. However, while many studies are being performed on enhancing the hydrogen storage properties of such alloys, there has been little research on large-scale storage vessels which make use of the alloys. In particular, large-scale, high-density storage devices must make allowances for the temperature variations caused by the heat of reaction between hydrogen and hydriding alloys, which may impact the storage characteristics. In this study, we propose a numerical model for the design and evaluation of hydrogen storage devices using hydriding alloys. Hydrogen desorption reaction behavior for an alloy is measured in terms of temperature, reaction rate and hydrogen concentration variation over time These data are then analyzed to yield a behavioral correlation which is used as the basis for a comprehensive simulation model of the alloy system. While a solid solution TiCrV-Fe alloy is used in the present study to gather these experimental data, the experimental procedure may be applied in an identical way to any metal hydride material subject to analysis. Calculated results of the model are found to be in good agreement with experimentally measured data. The accuracy of the model makes it useful in predicting the desorption behavior for a single system under multiple operating conditions. It can also be employed to evaluate multiple systems that satisfy a single set of given operating conditions. Given its accuracy and versatility, the model is expected to be highly useful in analyses of multiple system geometries, scales, and metal hydride alloy materials.