Investigation of the Disproportionation Reactions and Equilibrium of Lithium Difluoro(Oxalato) Borate (LiDFOB)

Lithium difluoro(oxalato) borate (LiDFOB) is a promising alternative lithium salt for lithium ion battery electrolytes. The ligand exchange reaction of LiDFOB to generate Lithium tetrafluoroborate (LiBF4) and lithium bis(oxalato)borate (LiBOB) was investigated by Nuclear Magnetic Resonance (NMR) spectroscopy. A thermally induced equilibrium exists between LiDFOB, LiBF4 and LiBOB. The activation barrier for conversion of LiDFOB to LiBF4 and LiBOB is 137 KJ mol−1 and the equilibrium favors LiDOFB by 14 KJ mol−1.