Work

Freestanding VS₂–sulfur hybrid cathode featuring a dual redox mechanism for high-loading and lean-electrolyte lithium–sulfur batteries

Year: 2025

Type: article

Abstract: The practical implementation of lithium‑sulfur batteries (LSBs) has long been hindered by several interlinked challenges, including low sulfur utilization, polysulfide shuttling, volumetric expansion, and high electrolyte-to‑sulfur (E/S) ratios. To address these limitations from a practical viability perspective, we designed a hybrid cathode architecture that synergistically combines sulfur's high capacity with the conductive and redox-active properties of 2D vanadium disulfide (VS₂). A freestanding, binder-free VS₂ nanostructure was synthesized on a mesh-type current collector, followed by the deposition of sulfur layers through thermal evaporation, resulting in the SS/VS₂/S cathode. This architecture enables both intercalation and conversion reactions while offering structural advantages, including enhanced electrolyte accessibility, efficient charge transport, and buffering of volumetric expansion during cycling. Furthermore, the VS₂ scaffold acts as a polar, conductive matrix that chemically anchors lithium polysulfides, mitigating the shuttle effect. The hybrid cathode demonstrated high active material loading (17.5 mg cm −2 ), a reduced E/AM ratio (~1.5), and stable electrochemical performance, delivering an areal capacity of 4.2 mAh cm −2 at 1 mA cm −2 . These findings reflect a balanced approach toward addressing key challenges in LSBs, showcasing the potential of this architecture for advancing high-energy lithium‑sulfur batteries.

Source: Journal of Energy Storage

DOI: 10.1016/j.est.2025.118926