A mathematical calculation of the hydriding characteristics of Mg2−xAxNi1−yBy alloy systems

Two semi-empirical models have been presented by the stepwise regression method and atomic parameters for the formation enthalpy (ΔH) in the hydriding process and the hydrogen storage capacity (C) of Mg2−xAxNi1−yBy alloy systems. The main factors influencing ΔH and C are given and we illustrate the relationship between the macroscopic characteristics and atomic structure. In general a decrease in ΔX2 and an increase in (e/a)2/3 as well as T will result in an increase of peq and ΔH. On the other hand, when ΔX2 and T increase but (e/a)2/3 and Z/R decrease, C will increase. The calculated results by the models presented in this paper are in good agreement with our experimental data, the calculated ΔH and C values were within 6.5 kJ mol−1 H and 0.5 mass% H.