Low-cost, high-energy-density lithium–sulfur electrochemical batteries have emerged as a promising solution for next-generation energy-storage technologies. To facilitate the practical application of such batteries, it is necessary to address the remaining scientific and engineering challenges, especially those associated with the high-loading sulfur cathode in a lean-electrolyte cell. In this study, we investigate the electrochemical and overall performance of lithium–sulfur cells with a high-loading sulfur cathode. Notably, this cathode is fabricated using a novel hot-pressing method and incorporates electronically and ionically conductive additives, specifically lithium lanthanum titanate (LLTO) and carbon black, respectively. Material analysis reveals the uniform distribution of additives in the cathodes, with the ionically conductive LLTO effectively adsorbing and converting polysulfides and carbon black enhancing the cathode conductivity. Electrochemical analysis of the lean-electrolyte cells shows that the incorporation of LLTO improves cell performance, with enhanced discharge capacity of 715–836 mAh g−1 at C/5–C/10 rates and notable capacity retention after 100 cycles, compared with cathodes without additives or with carbon black. Further investigations demonstrate the superior performance of the cell incorporating LLTO in a LiNO3-free electrolyte, attributable to the promotion of ion transport and polysulfide adsorption by LLTO, resulting in high discharge capacities (846 mAh g−1 at C/10), efficiency (93–99 %), and stability. Overall, this study compares the effects of electronically and ionically conductive additives on cell performance and highlights the effectiveness of the ionically conductive LLTO. The incorporation of such additives offers innovative solutions to the key challenges for the development of high-performance energy-storage devices.