A Nacre‐Like Carbon Nanotube Sheet for High Performance Li‐Polysulfide Batteries with High Sulfur Loading. Issue 6 (19th April 2018) - Pan, Zheng‐Ze
Abstract: Lithium‐sulfur (Li‐S) batteries are considered as one of the most promising energy storage systems for next‐generation electric vehicles because of their high‐energy density. However, the poor cyclic stability, especially at a high sulfur loading, is the major obstacles retarding their practical use. Inspired by the nacre structure of an abalone, a similar configuration consisting of layered carbon nanotube (CNT) matrix and compactly embedded sulfur is designed as the cathode for Li‐S batteries, which are realized by a well‐designed unidirectional freeze‐drying approach. The compact and lamellar configuration with closely contacted neighboring CNT layers and the strong interaction between the highly conductive network and polysulfides have realized a high sulfur loading with significantly restrained polysulfide shuttling, resulting in a superior cyclic stability and an excellent rate performance for the produced Li‐S batteries. Typically, with a sulfur loading of 5 mg cm −2, the assembled batteries demonstrate discharge capacities of 1236 mAh g −1 at 0.1 C, 498 mAh g −1 at 2 C and moreover, when the sulfur loading is further increased to 10 mg cm −2 coupling with a carbon‐coated separator, a superhigh areal capacity of 11.0 mAh cm −2 is achieved. Abstract : Lithium–sulfur batteries are one of the most promising energy storage systems for the next‐generation electric vehicles from the high theoretical energy density. From the unidirectional freeze‐drying approach, a nacre‐like carbon nanotube sheet is prepared and used as the cathode matrix. Such a structure with compact carbon nanotube matrix–sulfur configuration enables a considerably high performance at a high areal sulfur loading.