Mass transport in lithium-battery solvents

We describe and implement a microelectrode procedure for the determination of important transport properties required for the evaluation of liquid electrolytes used in lithium-based batteries. Three solvents of interest (propylene carbonate, ethylene carbonate, and diethyl carbonate) and two lithium salts (lithium hexafluorophosphate and lithium perchlorate) are investigated. In addition, by combining microelectrode and radiometric analyses, we are able to characterize fully the transport phenomena in the nonaqueous solvent + salt systems. Thus a radiometric technique is used to monitor solvent transport, both under diffusion and current-passage conditions, and the solvent diffusion coefficient is reported as a function of salt concentration.