Experiment and Modeling of Electrochemical Performance of Lithium-Sulfur Batteries with Varying Carbon to Sulfur Ratios

Lithium-sulfur batteries have attracted much research interest due to their high theoretical energy density and low cost raw materials. While the electrodes are comprised of readily available materials, the processes that occur within the cell are complex and the electrochemical performance of these batteries is very sensitive to a number of cell processing parameters. In this poster, a simple electrochemical model will be presented and will be used to predict, with quantitative agreement, the electrochemical properties of lithium-sulfur cathodes with varying carbon to sulfur ratios. The experimental polarization was accurately captured by the model, including a transition in the capacity and polarization at higher sulfur loading. In addition, a transition in the electrode morphology – from well dispersed to aggregated sulfur at the surface – will be reflected in the change in a critical model parameter demonstrating the sensitivity and functionality of even this simple model in predicting complex behavior in the lithium-sulfur cells.