International Journal of Hydrogen Energy, Vol.45, No.32, 16239-16253, 2020
Performance prediction of a coupled metal hydride based thermal energy storage system
The present study discusses the thermodynamic compatibility criteria for the selection of metal hydride pairs for the application in coupled metal hydride based thermal energy storage systems. These are closed systems comprising of two metal hydride beds - a primary bed for energy storage and a secondary bed for hydrogen storage. The performance of a coupled system is analyzed considering Mg2Ni material for energy storage and LaNi5 material for hydrogen storage. A 3-D model is developed and simulated using COMSOL Multiphysics (R) at charging and discharging temperatures of 300 degrees C and 230 degrees C, respectively. The LaNi5 bed used for hydrogen storage is operated close to ambient temperature of 25 degrees C. The results of the first three consecutive cycles are presented. The thermal storage system achieved a volumetric energy storage density of 156 kWh m(-3) at energy storage efficiency of 89.4% during third cycle. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.