Structural Insights into Borohydride-Halide Li-Ion Conductors, LiM(BH4)X (X= Cl, Br, M = Ce, Pr)

Solid state electrolytes are key components to replace volatile liquid electrolytes in lithium-based batteries to deal with the safety concern. We propose here variable temperature Powder Neutron Diffraction experiment of synthesised lithium ion conductors, LiCe(BH4)3X (X = Cl, Br) and LiPr(BH4)3Cl . We would extract precise crystal structure parameters such as positions, site occupancy factors for the 7Li, 11B and D (and lanthanide) atoms within the structure and accurate phase fractions of the compounds vs. the binary halide by-products (produced during synthesis). The proposed temperature-dependent PND data (from ambient -150 oC at 20 °C intervals) for the LiCe(BH4)3X (X = Cl, Br) and LiPr(BH4)3Cl will correlate the thermally-activated ion transport properties (as measured by electrochemical impedance spectroscopy) to their structure and intrinsic defects.