The recent research status quo and the prospect of electrolytes for lithium sulfur batteries

Abstract

Soaring demand for efficient and economic electric energy storage system has intensively promoted the development of rechargeable batteries. Lithium sulfur battery may be one of the most promising candidates in the frontier of modern electrochemistry owing to its high theoretical specific capacity (1672 mAh g−1), high energy density (2600 Wh kg−1), low cost, and environmentally friendliness. However, the deactivation of active substances and polarization of electrodes caused by “shuttle effect” hampered commercial applications of lithium sulfur batteries. The explosiveness of research on lithium-sulfur batteries in recent years acquired outstanding breakthroughs and achievements in solving the aforementioned problems. Particularly, standing the perspective of electrolyte, as a transmission medium of all ions in the redox reaction, it is important to inhibit the dissolution and diffusion of polysulfide. Here, a comprehensive overview of the recent advance of electrolyte including liquid electrolyte and a solid electrolyte in lithium sulfur battery is presented. For the liquid electrolyte, it mainly concentrates on modifying electrolyte to improve the interfacial architectures and properties, including the changing of solvent, selecting of salts or additives and matching anion and cation of the ionic liquid. In order to ameliorate the high interface impedance and poor ion conductivity under an atmospheric temperature of the solid electrolyte, various methods were proposed, which contains building novel structures of the gel electrolyte, introducing inorganic particles into the polymer, modifying the inorganic solid electrolyte and constructing composite electrolyte. Finally, some perspectives on the future research and development of electrolyte in lithium sulfur battery are provided.