Determination of Lithium-Ion Transference Numbers in LiPF[sub 6]–PC Solutions Based on Electrochemical Polarization and NMR Measurements

Abstract

The electrolyte plays an important role in governing the performance of Li-ion batteries. To understand more about the role of the electrolyte, transport properties such as the lithium salt self-diffusion coefficient and the lithium-ion transference number need to be measured. In this study, the diffusion coefficient was determined by pulsed field gradient nuclear magnetic resonance (NMR). The lithium-ion transference number was determined by an electrochemical polarization method and also calculated on the basis of diffusion coefficients, which were obtained by NMR measurement, of and in the solutions of in propylene carbonate. The lithium-ion transference number and the diffusion coefficient were found to be strongly dependent on the concentration.