Preventing the Dissolution of Lithium Polysulfides in Lithium-Sulfur Cells by using Nafion-coated Cathodes

The principal drawback of lithium–sulfur batteries is the dissolution of long‐chain lithium polysulfides into the electrolyte, which limits cycling performance. To overcome this problem, we focused on the development of a novel cathode as well as anode material and designed Nafion‐coated NiCrAl/S as a cathode and lithium powder as an anode. Nafion‐coated NiCrAl/S cathode was synthesized using a two‐step dip‐coating technique. The lithium‐powder anode was used instead of a lithium‐foil anode to prohibit dendrite growth and to improve on the electrochemical behaviors. The cells showed an initial discharge capacity of about 900 mA g−1 and a final discharge capacity of 772 mA g−1 after 100 cycles at 0.1 C‐rate. Scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS) demonstrate that using the Nafion‐coated NiCrAl/S cathode can suppress the dissolution of long‐chain lithium polysulfides. My humble anode: A new system for lithium–sulfur batteries is reported. The cells comprise Nafion‐coated NiCrAl/S as cathode and lithium powder as anode material. The materials hamper the dissolution of long‐chain lithium polysulfides into the electrolyte, thereby improving cycling performance. Electrochemical analysis shows high initial discharge capacities, coupled to good capacity retention values after 100 cycles.