Abstract
Lithium sulfur (Li-S) batteries stand out among many new batteries for their high energy density. However, the intermediate charge–discharge product dissolves easily into the electrolyte to produce a shuttle effect, which is a key factor limiting the rapid development of Li-S batteries. Among the various materials used to solve the challenges related to pure sulfur cathodes, biomass derived carbon materials are getting wider research attention. In this work, we report on the fabrication of cathode materials for Li-S batteries based on composites of sulfur and biomass-derived porous ramie carbon (RC), which are coated with multiwalled carbon nanotubes (MWCNTs). RC can not only adsorb polysulfide in its pores, but also provide conductive channels. At the same time, the MWCNTs coating further reduces the dissolution of polysulfides into the electrolyte and weakens the shuttle effect. The sulfur loading rate of RC is 66.3 wt.%. As a result, the initial discharge capacity of the battery is 1325.6 mAh·g−1 at 0.1 C long cycle, and it can still maintain 812.5 mAh·g−1 after 500 cycles. This work proposes an effective double protection strategy for the development of advanced Li-S batteries.
Highlights
With the growing energy crisis and serious global environmental issues, it is urgent to develop renewable and clean energy technologies [1]
Lithium sulfur (Li-S) batteries suffer from several drawbacks such as the relatively poor conductivity of sulfur, volume expansion, and most severely, the shuttle effect of lithium polysulfide, which leads to the rapid degradation of battery performance during the electrochemical cycling [10,11,12,13]
We use ramie carbon (RC) prepared by a ZnCl2 chemical activation method as a host material
Summary
With the growing energy crisis and serious global environmental issues, it is urgent to develop renewable and clean energy technologies [1]. Li-S batteries suffer from several drawbacks such as the relatively poor conductivity of sulfur, volume expansion, and most severely, the shuttle effect of lithium polysulfide, which leads to the rapid degradation of battery performance during the electrochemical cycling [10,11,12,13] To tackle these problems, various strategies have been developed to optimize the sulfur cathode [14,15,16,17,18,19,20]. A simple optimization method was used to prepare the MWCNTs positive protective coating In this composite cathode, the porous structure of RC can effectively bind polysulfides and improve the volume expansion during charge discharge. The MWCNTs further reduce the dissolution of polysulfides in the electrolyte, which in turn further attenuates the polysulfide shuttle effect In this way, the RCS composite cathodes coated with MWCNTs can greatly improve the overall battery performance, which exhibits an initial discharge specific capacity of 1325.0 mAh·g−1 at.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
