The study of hydrogen interaction with NdNi5-xAlx alloys (0 <= x <= 1) and the refinement of thermodynamic parameters of hydriding reactions were performed in this work. The enthalpies and entropies of desorption reactions were calculated from the PCT-isotherms data and using our phenomenological model. Obtained results were compared with the literature data. The comparison of our experimental and calculated data proves the validity of the proposed model for prognosis of hydrogen absorption properties of alloys. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.