Influence of Sulfur Loading on Lithium-Sulfur Battery Performance for Different Cathode Carbon Types

Since lithium-sulfur (Li-S) batteries often employ an excess of carbon in the cathode to obtain high electrical conductivity and surface area, the kind and qualities of the carbon in the cathode significantly impact battery performance. Sulfur loading is an essential design element with a considerable influence on battery performance. To anticipate the relationship between the sulfur loading and the cycling performance, discharge capacity, and energy density/specific energy at the cell/pack level of the Li-S battery for different carbon types, an integrated research technique that couples experimental characterization and system-level performance modeling is used. The capacity retention of Li-S cells with acetylene black is insensitive to S loading, while Li-S cells with carbon black present higher capacity retention at higher S loadings. Li-S cells with Ketjen Black cannot perform well at higher S loadings. At moderate S loadings, when discharge capacities are at maximum, Li-S cells achieve the highest system-level metrics.