• 文献标题:   Suppressed Polysulfide Crossover in Li-S Batteries through a High-Flux Graphene Oxide Membrane Supported on a Sulfur Cathode
  • 文献类型:   Article
  • 作  者:   SHAIBANI M, AKBARI A, SHEATH P, EASTON CD, BANERJEE PC, KONSTAS K, FAKHFOURI A, BARGHAMADI M, MUSAMEH MM, BEST AS, RUTHER T, MAHON PJ, HILL MR, HOLLENKAMP AF, MAJUMDER M
  • 作者关键词:   lithiumsulfur battery, shearaligned graphene oxide membrane, polysulfide retention, high sulfur content
  • 出版物名称:   ACS NANO
  • ISSN:   1936-0851 EI 1936-086X
  • 通讯作者地址:   Monash Univ
  • 被引频次:   74
  • DOI:   10.1021/acsnano.6b03285
  • 出版年:   2016

▎ 摘  要

Utilization of permselective membranes holds tremendous promise for retention of the electrode-active material in electrochemical devices that suffer from electrode instability issues. In a rechargeable Li-S battery-a strong contender to outperform the Li-ion technology migration of lithium polysulfides from the sulfur cathode has been linked to rapid capacity fading and lower Coulombic efficiency. However, the current approaches for configuring Li-S cells with permselective membranes suffer from large ohmic polarization, resulting in low capacity and poor rate capability. To overcome these issues, we report the facile fabrication of a high-flux graphene oxide membrane directly onto the sulfur cathode by shear alignment of discotic nematic liquid crystals of graphene oxide (GO). In conjunction with a carbon-coated separator, the highly ordered structure of the thin (similar to 0.75 mu m) membrane and its inherent surface charge retain a majority of the polysulfides, enabling the cells to deliver very high initial discharge capacities of 1063 and 1182 mAh g(electrode)(-1) for electrodes with 70 and 80% sulfur content, respectively, at the practical 0.5 C rate. The very high sulfur utilization and impressive capacity retentions of the high sulfur content electrodes result in some of the highest performance metrics in the literature of Li-S (e.g., electrode capacity of 835 mAh gelectrode after 100 cycles at 0.5 C with a sulfur content of 80%). We show that the structural order of the shear-aligned GO membrane is key in maintaining good kinetics of the charge transfer processes in Li-S batteries.