Selective Catalysis Remedies Polysulfide Shuttling in Lithium‐Sulfur Batteries
Wuxing Hua, Huan Li, Chun Pei, Jingyi Xia, Yafei Sun, Chen Zhang, Wei Lv, Ying Tao, Yan Jiao, Bingsen Zhang, Shi‐Zhang Qiao, Ying Wan, Quan‐Hong Yang
Abstract
Abstract The shuttling of soluble lithium polysulfides between the electrodes leads to serious capacity fading and excess use of electrolyte, which severely bottlenecks practical use of Li‐S batteries. Here, selective catalysis is proposed as a fundamental remedy for the consecutive solid‐liquid‐solid sulfur redox reactions. The proof‐of‐concept Indium (In)‐based catalyst targetedly decelerates the solid‐liquid conversion, dissolution of elemental sulfur to polysulfides, while accelerates the liquid‐solid conversion, deposition of polysulfides into insoluble Li 2 S, which basically reduces accumulation of polysulfides in electrolyte, finally inhibiting the shuttle effect. The selective catalysis is revealed, experimentally and theoretically, by changes of activation energies and kinetic currents, modified reaction pathway together with the probed dynamically changing catalyst (LiInS 2 catalyst), and gradual deactivation of the In‐based catalyst. The In‐based battery works steadily over 1000 cycles at 4.0 C and yields an initial areal capacity up to 9.4 mAh cm −2 with a sulfur loading of ≈9.0 mg cm −2 .