Reinvestigation of ionic conductivity of a layered Li(BH3NH2BH2NH2BH3) salt

Abstract

We reinvestigated ionic conductivity of lithium ions for Li(BH3NH2BH2NH2BH3), an ammonia borane derivative. The observed conductivity (4.0x10–6 S/cm at 65°C) was found to be over four orders of magnitude higher than the value reported previously at 70oC for this compound. Since very slow thermal decomposition of Li(BH3NH2BH2NH2BH3) progresses already below 100°C, the previous results reported for 70–130°C most likely correspond to decomposed samples. The activation energy for lithium conductivity of polycrystalline layered Li(BH3NH2BH2NH2BH3) (57 kJ/mol) resembles that for powdered Li3N (59 kJ/mol) suggesting similar mechanism of lithium diffusion in both materials.