Jump to main content
Jump to site search

Issue 1, 2017
Previous Article Next Article

3D graphene framework supported Li2S coated with ultra-thin Al2O3 films: binder-free cathodes for high-performance lithium sulfur batteries

Author affiliations

Abstract

Lithium sulfide (Li2S) has drawn special attention as a promising cathode material for emerging energy storage systems due to its high theoretical specific capacity and great compatibility with lithium metal-free anodes. However, Li2S cathodes urgently require a solution to increase their poor electrical conductivity and to suppress the dissolution of long-chain polysulfide (Li2Sn, 4 ≤ n ≤ 8) species into electrolyte. To this end, we report a free-standing Al2O3–Li2S–graphene oxide sponge (GS) composite cathode, in which ultrathin Al2O3 films are preferentially coated on Li2S by an atomic layer deposition (ALD) technique. As a result, a combination of high electron conductivity (from GS) and strong binding with Li2Sn (from ultrathin Al2O3 films) was designed for cathodes. The newly developed Al2O3–Li2S–GS cathodes are able to deliver a highly reversible capacity of 736 mA h gLi2S−1 (427 mA h gcathode−1) at 0.2C, which is much higher than that of corresponding cathodes without Al2O3 (59%). Also, the long-term cycling stability of Al2O3–Li2S–GS cathodes was demonstrated up to 300 cycles at 0.5C with an excellent capacity retention of 88%. In addition, combined with density functional theory calculations, the promotional mechanism of ultrathin Al2O3 films was elucidated using extensive characterization. The ultra-thin Al2O3 film with optimal thickness not only acts as a physical barrier to Li2S nanoparticles, but provides a strong binding interaction to suppress Li2Sn species dissolution.

Graphical abstract: 3D graphene framework supported Li2S coated with ultra-thin Al2O3 films: binder-free cathodes for high-performance lithium sulfur batteries

Back to tab navigation

Supplementary files

Publication details

The article was received on 16 Sep 2016, accepted on 10 Oct 2016 and first published on 11 Oct 2016


Article type: Paper
DOI: 10.1039/C6TA08039A
Citation: J. Mater. Chem. A, 2017,5, 102-112
  •   Request permissions

    3D graphene framework supported Li2S coated with ultra-thin Al2O3 films: binder-free cathodes for high-performance lithium sulfur batteries

    Y. Chen, S. Lu, J. Zhou, X. Wu, W. Qin, O. Ogoke and G. Wu, J. Mater. Chem. A, 2017, 5, 102
    DOI: 10.1039/C6TA08039A

Search articles by author

Spotlight

Advertisements