A COUPLED EXPERIMENTAL AND MECHANISTIC MODELING APPROACH TO VIRTUAL PROTOTYPING LITHIUM-SULFUR BATTERIES THE OBJECTIVE OF THIS PROJECT IS TO DEVELOP MECHANISTIC MODELS OF THE LITHIUM-SULFUR (LI-S) BATTERY CATHODE PROCESSES THAT ARE EXPERIMENTALLY VALIDATED AND CAPABLE OF VIRTUALLY PROTOTYPING THE LI-S CELLS WITH HIGH CONFIDENCE THAT WILL LEAD TO TARGETED MATERIALS AND ELECTRODE DESIGN TO IMPROVE CATHODE ENERGY DENSITY AND CYCLE LIFE. ACTIVITIES INCLUDE INITIAL AND BASELINE LI-S BATTERY DATA COLLECTION AND INITIATING THE MULTI-SPECIES, MULTI-REACTION (MSMR) MODELING APPROACH. THE MSMR MODEL WILL BE COUPLED TO EXPERIMENTAL DATA AND VALIDATED AND EXPANDED LI-S BATTERY EXPERIMENTATION AND POROUS ELECTRODE MODELING AND PARAMETER ESTIMATION COUPLED TO THE EXPERIMENTAL DATA WILL BE INITIATED. THE CONSTRUCTION OF LI-S POUCH CELLS WILL BE FINALIZED AND VOLUME EXPANSION WILL BE MEASURED EXPERIMENTALLY. THIS DATA WILL BE USED TO DEVELOP AND VALIDATE A VOLUME EXPANSION MODEL. VIRTUAL PROTOTYPING WITH THE COUPLED MODELS WILL BE CONDUCTED.