High sulfur-containing carbon polysulfide polymer as a novel cathode material for lithium-sulfur battery

Yiyong Zhang,Jing Wang,Jing Zeng,Bing Joe Hwang,Jinbao Zhao,Jiyang Li,He Li,Yueying Peng,Yunhui Wang

doi:10.1038/s41598-017-11922-6

Abstract

The lithium-sulfur battery, which offers a high energy density and is environmental friendly, is a promising next generation of rechargeable energy storage system. However, despite these attractive attributes, the commercialization of lithium-sulfur battery is primarily hindered by the parasitic reactions between the Li metal anode and dissolved polysulfide species from the cathode during the cycling process. Herein, we synthesize the sulfur-rich carbon polysulfide polymer and demonstrate that it is a promising cathode material for high performance lithium-sulfur battery. The electrochemical studies reveal that the carbon polysulfide polymer exhibits superb reversibility and cycle stability. This is due to that the well-designed structure of the carbon polysulfide polymer has several advantages, especially, the strong chemical interaction between sulfur and the carbon framework (C-S bonds) inhibits the shuttle effect and the π electrons of the carbon polysulfide compound enhance the transfer of electrons and Li+. Furthermore, as-prepared carbon polysulfide polymer-graphene hybrid cathode achieves outstanding cycle stability and relatively high capacity. This work highlights the potential promise of the carbon polysulfide polymer as the cathode material for high performance lithium-sulfur battery.

Highlights

With the rapid development of mobile electronic devices and electric vehicles on the market, the batteries to be used as power supplies are more urgently required to have higher performances
Li and co-workers designed a structure of carbon-sulfur matrix cathode with physical and chemical confinement, which was crucially important for high performance lithium-sulfur batteries
This well-designed structure has several advantages: (1) the carbon polysulfide polymer has a highly uniform structure and high sulfur content; (2) the strong chemical interaction of sulfur with the carbon framework (C-S bonds) inhibits the shuttle effect; (3) the π electrons of the carbon polysulfide polymer enhance the transfer of electron and Li+; (4) the conductive graphene can provide the paths for fast electron transport and accommodate sulfur volume expansion

Summary

Introduction

With the rapid development of mobile electronic devices and electric vehicles on the market, the batteries to be used as power supplies are more urgently required to have higher performances. When fabricated by using this copolymer as cathode, which exhibited the initial specific capacity of 1143 mAh g−1 at 0.1 C and 595 mAh g−1 at 1 C These sulfur copolymers provide a new way for the use of chemically confined polysulfides in the lithium-sulfur batteries, their poor conductivity has hindered the achievement of good cycling and rate performance. We report a sulfur-rich carbon polysulfide polymer-graphene hybrid cathode for the lithium-sulfur batteries produced by chemical confinement strategies This well-designed structure has several advantages: (1) the carbon polysulfide polymer has a highly uniform structure and high sulfur content; (2) the strong chemical interaction of sulfur with the carbon framework (C-S bonds) inhibits the shuttle effect; (3) the π electrons of the carbon polysulfide polymer enhance the transfer of electron and Li+; (4) the conductive graphene can provide the paths for fast electron transport and accommodate sulfur volume expansion. A carbon polysulfide polymer-graphenen hybrid cathode delivers excellent cycling performance for 100 cycles with a high specific capacity of 600 mAh g−1 at the current density of 200 mA g−1

Methods

Results

Conclusion