Improved thermodynamic properties of doped LiBH4 for hydrogen storage: First-principal calculation

Abstract

First-principles calculations have been performed on lithium borohydride LiBH4 using the ultrasoft pseudopotential method, which is a potential candidate for hydrogen-storage materials due to its extremely large gravimetric capacity of 18 mass % hydrogen. We focus on an orthorhombic phase observed at ambient conditions and predict its fundamental properties; De-hydrogenation and electronic properties of doped Li1+xB1−xH4 by Li (with 0 < x < 0.75); to be used as a material for hydrogen-storage; are studied from density-functional theory based first-principles calculations. The results suggest that the substitution of B by Li decrease the desorption enthalpy of hydrogen from 75 kJ/mol.l to 40. Our calculation results show the function of Li in improving thermodynamics, which provides a favorable thermodynamic modification.