Flexible Titanium Nitride‐Based Membrane Reactor for S<sub>8</sub>/Li<sub>2</sub>S and Dendrite Regulation in Lithium‐Sulfur Batteries
Lei Ji, Daotong Yang, Jiayi Xue, Min Jia, Tong Wu, Quan Zhuang, Yingying Zhang, Yingying Zhang, Jinghai Liu, Yuegang Zhang, Yuegang Zhang
Abstract
Abstract Simultaneous regulation of S 8 /Li 2 S solid‐liquid redox conversion at the cathode and lithium (Li) dendrite growth at the anode is essential for advancing lithium‐sulfur (Li─S) batteries. Herein, a flexible titanium nitride‐based membrane (TiNOCF) is developed as a membrane reactor (MR) to enhance sulfur redox kinetics, activates S 8 /Li 2 S solid and guide dendrite horizontal growth. The TiNOCF MR at the sulfur cathode side endows the Li─S cell with a remarkable high‐rate capacity of 851.4 mAh g −1 and a stable cycling retention of 94.8% after 200 cycles at 5 C. At the Li anode side, it maintains the Li/Li cell with stable cycling for 2000 h with an ultra‐low overpotential of 38.1 mV at a current density of 2 mA cm −2 . For high sulfur‐loading, TiNOCF MR gives the full cells (10 mg sulfur cm −2 ) with an areal capacity of 10.2 mAh cm −2 at 0.1 C and the pouch cells (9.5 mg sulfur cm −2 ) with 10.9 mAh cm −2 at 36 mA. Mechanism analysis reveals the key roles of titanium (Ti 3+ ) and nitrogen (N 3− ) sites in confinement catalysis and directional dendrite growth, enabling high‐areal capacity, fast‐charging and stable‐cycling features.