Abstract

Lithium-sulfur batteries (LSBs) have attracted significant attention as next-generation high-energy-density storage systems owing to the high theoretical capacity of sulfur, its natural abundance, and low cost. However, the practical realization of cell-level energy density remains challenging due to intrinsic limitations, including the low electrical conductivity of active material, the polysulfide shuttle phenomenon, and large volume changes. To achieve practical high-energy density, thick sulfur cathodes with high sulfur loading are required. In thick electrodes, limitations in electronic and ionic transport, reaction inhomogeneity, and structural instability become more pronounced. Dry electrode processes are emerging as a promising alternative for designing thick LSB electrodes, as they can overcome the structural limitations of wet-based processes while enabling high electrode density and more uniform conductive networks. This review provides a systematic overview of design strategies for dry thick LSB electrodes and discusses approaches to mitigate key performance-limiting factors. Furthermore, reaction mechanisms and transport phenomena are analyzed through in situ/operando characterization, and design directions for the realization of practical high-energy-density cells are proposed. This review aims to facilitate the development of practical high-energy-density LSBs by outlining structural design principles and research directions in dry thick-electrode technologies.