CRG proposes to develop an Advanced Lithium Sulfur Battery (LSB) based on combining a novel super ion conducting ceramic electrolyte, entrapped sulfur cathode, and a lithium metal anode necessary to meet NASA's needs for high energy density, rechargeable, and safe energy storage. These new materials for LSBs will build upon a proven ceramic electrolyte for rechargeable lithium metal batteries. A composition of a metallic lithium anode, ceramic electrolyte, and a novel sulfur cathode will be optimized to achieve program goals for energy density, operational temperatures, storage, and cycle life. Supporting the Human Exploration and Operations Directorate, this project's technologies directly address requirements for high energy density space batteries for space exploration systems including rovers, landers, ascent vehicle space craft. This project's technologies offer high energy density (>450 Whr/kg), long storage life, and long operational life batteries. These advancements will enable space power supplies to keep pace with increasing electricity demands, and reduce battery weight by 50% while advancing the state of the art battery technology.