A sandwich-structured TiN/BN-C composite interlayer with enhanced performance for LiS batteries

Publication date: Available online 16 February 2020Source: Journal of Electroanalytical ChemistryAuthor(s): Jinghui Zhu, Caiming Jiao, Tuo Kang, Liubiao Zhong, Sanfei Zhao, Yejun QiuAbstractAiming to commercialize LiS battery, it is very important to achieve high sulfur loading alongside superior electrochemical performance. In this work, a novel composite material with sandwich structure constructed by titanium nitride nanoparticles and boron nitride‑carbon nanofibers (BNC-TiN-BNC), has been successfully prepared through electrospinning and spraying method, and applied as the interlayer in LiS batteries. Compared with the BNCNF interlayer, the sandwich-like BNC-TiN-BNC interlayer shows more excellent chemical adsorption for soluble lithium polysulfides (LiPSs) via the polar effects of the TiS and SN bonds, and furthermore, the uniform distribution of TiN nanoparticles, filling in the pores between the nanofibers as packing layer of the BNC-TiN-BNC interlayer, can retard the migration of LiPSs more effectively by physical barriers. By introducing the BNC-TiN-BNC interlayer, the electron transfer, capacity and cycling life of LiS batteries have been improved significantly, especially at high current density. With the sulfur loading of 2.5 mg cm−2, the cell with BNC-TiN-BNC interlayer delivers a high initial discharge capacity of 642.3 mA h g−1 at high current density of 2.0C, and the capacity remains 594 mA h g−1 with only the decay rate of 0.025% over ...
Source: Journal of Electroanalytical Chemistry - Category: Chemistry Source Type: research