In this study, hydrogen storage capacity were analyzed by considering hydrogen absorption test rig depending on some reactor design parameters such as metal hydride particle size, having fins at the tank, hydrogen inlet pressure, inlet radius of the tank, coolant temperature, general convective heat transfer coefficient and wall thickness of the tank. In the specified design parameters of the hydrogen storage system we put these in COMSOL Multiphysics 5.1 software to obtain some approaches in the large scale. All parameters were analyzed using three different metal hydrides of the MmNi(4,6)Al(0,4), LaNi4.75Al0.25 and LaNis. Some parameters like temperature distribution inside the tank, amount of the hydrogen mass to be stored in the tank, the time durations of them and the variations of the equilibrium pressure of the system were optimized. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.