Hydrogen charging and discharging studies on embedded cooling tube metal hydride reactor designed for fuel cell applications

In the present study, an embedded cooling tube (ECT) type metal hydride (MH) reactor has been designed, manufactured, and tested for possible integration with a low-temperature Polymer Electrolyte Membrane Fuel Cell (LT-PEMFC) at 40-60 degrees C. The MH reactor filled with 21.5 kg La0.9Ce0.1Ni5 has been subjected to a series of parametric tests. At 20 bar, 25 degrees C, the MH reactor absorbed 276.08 g hydrogen in 1129 s, accounting for 1.28 wt.% charged capacity. At 40 degrees C, the reactor desorbed 282.8 g hydrogen within 4860 s, which, if discharged through a mass flow controller (MFC) at a steady rate, could feed a 3.5 kW LT-PEMFC for the same duration maintaining the reactor pressure above 1 bar. An increase in discharging temperature to 60 degrees C showed about 54% increase in average hydrogen discharge rate. Influence of variation in heat transfer fluid (HTF) flow rate was discovered to be insignificant for both charging and discharging. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.