Practically Accessible All-Solid-State Batteries Enabled by Organosulfide Cathodes and Sulfide Electrolytes

The combination of organic electrode materials and sulfide electrolytes is expected to enable the development of all-solid-state organic batteries featuring high energy density, safety, and sustainability. Here, thiuram hexasulfide is first reported as a low-cost and high-capacity cathode material for solid-state organic batteries based on sulfide electrolytes. Notably, a capacity of ≈600 mA h g⁻¹ is delivered and the capacity retention is 80.8% after 500 cycles. An electrochemically reversible change of the cathode interface is revealed upon cycling. The full cell displays an oscillating stress change of up to 0.6 MPa during cycling, predominated by the anode side. The energy density is 1140 Wh kg⁻¹ at the material level and 376 Wh kg⁻¹ at the electrode level, which are among the best-reported organic cathodes to date. A high areal capacity of 10.4 mA h cm⁻² is reached with a high mass loading cathode. A dry-film approach is further explored to manufacture sheet-type cells. The free-standing Li₆PS₅Cl film with a thickness of only 48 µm demonstrates an ultralow areal resistance of 3.9 Ω cm², which significantly boosts the cell-level energy density and reduces the cell internal resistance.