Two-dimensional layered transition metal disulphides for effective encapsulation of high-capacity lithium sulphide cathodes
Abstract
Fully lithiated lithium sulphide (Li2S) is currently being explored as a promising cathode material for emerging energy storage applications. Like their sulphur counterparts, Li2S cathodes require effective encapsulation to reduce the dissolution of intermediate lithium polysulphide (Li2Sn, n=4-8) species into the electrolyte. Here we report, the encapsulation of Li2S cathodes using two-dimensional layered transition metal disulphides that possess a combination of high conductivity and strong binding with Li2S/Li2Sn species. In particular, using titanium disulphide as an encapsulation material, we demonstrate a high specific capacity of 503 mAh g-1Li2S under high C-rate conditions (4C) as well as high areal capacity of 3.0 mAh cm-2 under high mass-loading conditions (5.3 mgLi2S cm-2). This work opens up the new prospect of using transition metal disulphides instead of conventional carbon-based materials for effective encapsulation of high-capacity electrode materials.
- Publication:
-
Nature Communications
- Pub Date:
- September 2014
- DOI:
- 10.1038/ncomms6017
- Bibcode:
- 2014NatCo...5.5017S