In situ wrapping of the cathode material in lithium-sulfur batteries

• Published in: Nature communications Vol. 8; no. 1; pp. 479 - 9
• Main Authors: Hu, Chenji, Chen, Hongwei, Shen, Yanbin, Lu, Di, Zhao, Yanfei, Lu, An-Hui, Wu, Xiaodong, Lu, Wei, Chen, Liwei
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 07.09.2017; Nature Publishing Group; Nature Portfolio
• Subjects: 704/844/4066/4067; 704/844/4066/4069; Batteries; Cathodes; Diffusion layers; Electrode materials; Energy storage; Humanities and Social Sciences; Infiltration; Lithium; Lithium sulfur batteries; multidisciplinary; Particulate composites; Polysulfides; Science; Science (multidisciplinary); Sulfur
• DOI: 10.1038/s41467-017-00656-8
• ISSN: 2041-1723

While lithium–sulfur batteries are poised to be the next-generation high-density energy storage devices, the intrinsic polysulfide shuttle has limited their practical applications. Many recent investigations have focused on the development of methods to wrap the sulfur material with a diffusion barrier layer. However, there is a trade-off between a perfect preassembled wrapping layer and electrolyte infiltration into the wrapped sulfur cathode. Here, we demonstrate an in situ wrapping approach to construct a compact layer on carbon/sulfur composite particles with an imperfect wrapping layer. This special configuration suppresses the shuttle effect while allowing polysulfide diffusion within the interior of the wrapped composite particles. As a result, the wrapped cathode for lithium–sulfur batteries greatly improves the Coulombic efficiency and cycle life. Importantly, the capacity decay of the cell at 1000 cycles is as small as 0.03% per cycle at 1672 mA g –1 . To suppress the polysulfide shuttling effect in Li-S batteries, here the authors report a carbon/sulfur composite cathode with a wrapping layer that overcomes the trade-off between limiting polysulfide diffusion and allowing electrolyte infiltration, and affords extraordinary cycling stability.