By doping with 5 wt TiF4 and activated carbon (AC), onset and main dehydrogenation temperatures of MgH2 significantly reduce (Delta T = 138 and 109 degrees C, respectively) with hydrogen capacity of 4.4 wt % H-2. Up-scaling to storage tank begins with packing volume and sample weight of 28.8 mL and similar to 14.5 g, respectively, and continues to 92.6 mL and similar to 60.5-67 g, respectively. Detailed hydrogen sorption mechanisms and kinetics of the tank tightly packed with four beds of MgH2-TiF4-AC (similar to 60.5 g) are investigated. De/rehydrogenation mechanisms are detected by three temperature sensors located at different positions along the tank radius, while hydrogen permeability is benefited by stainless steel mesh sheets and tube inserted in the hydride beds. Fast desorption kinetics of MgH2-TiF4-AC tank at similar to 275-283 degrees C, approaching to onset dehydrogenation temperature of the powder sample (272 degrees C) suggests comparable performances of laboratory and tank scales. Hydrogen desorption (T = 300 degrees C and P(H-2) = 1 bar) and absorption (T = 250 degrees C and P(H-2) = 10-15 bar) of MgH2-TiF4 AC tank provide gravimetric and volumetric capacities during the 1st-2nd cycles of 4.46 wt % H-2 and 28 gH(2)/L, respectively, while those during the 3rd -15th cycles are up to 3.62 wt % H-2 and 23 gH(2)/L, respectively. Due to homogeneous heat transfer along the tank radius, de/rehydrogenation kinetics superior at the tank center and degrading forward the tank wall can be due to poor hydrogen permeability. Particle sintering and/or agglomeration upon cycling yield deficient hydrogen content reproduced. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.