ABSTRACT
Electrochemical measurements are often done using three compartment glass cells. The measuring set consists of tested electrode, reference electrode and counter electrode. Before measurement, material which is most often in powder form should be mixed with nickel. Addition of nickel to electrode material increases electrical conductivity, catalyzes electrode reaction and surface dissociation, prevents the diffusion of oxygen to the internal part of the alloy, and increases a cycle life of electrodes. It is important to note that by electrochemical measurements, it is possible to obtain pressure-composition-temperature (PCT) isotherms, which describe the dependence of the hydrogen equilibrium pressure to the amount of hydrogen dissolved and/or incorporated into the solid phase at different constant temperatures. The disadvantage of using electrochemical devices for obtaining PCT curves is that it can be applied only for metal hydride alloys that can be electrochemically charged/discharged.
