Research on lithium batteries, the urgent need for high energy density batteries, and attention to battery safety issues, It is an inevitable trend to use solid electrolyte instead of traditional liquid electrolyte in lithium-sulfur battery. The ideal solid electrolyte for lithium-sulfur batteries needs to meet the following requirements:  

1. Good mechanical properties;   

2. The lithium ion conductivity is equivalent to the liquid phase of liquid electrolyte;   

3. Good chemical stability and interface compatibility when contacting electrode;   

4. Comprehensive performance of inhibiting polysulfide ion shuttle and ultra-high safety.   

But solving these problems at the same time is very challenging because different types of solid electrolyte materials have their advantages and disadvantages.  All solid polymer electrolyte has good safety, It has good interface contact and compatibility with the electrode, but the ionic conductivity at room temperature is low and the mechanical properties are poor, so the application research in lithium sulfur battery is few. Due to its high ionic conductivity and low interfacial impedance with sulfur electrode, gel polymer electrolyte has made some progress in lithium-sulfur batteries.  

It has a good application prospect.  The ionic conductivity of ceramic electrolyte is high and stable, but the interface impedance of electrolyte/electrode is large, so the ionic conductivity still cannot meet the application requirements of lithium sulfur battery. Therefore, there are few studies on ceramic electrolytes in lithium-sulfur batteries.  Due to the advantages of both polymer and inorganic electrolytes, composite electrolytes are the most promising for satisfying a variety of properties simultaneously. However, there are still a lot of scientific and technical problems to be solved. The microscopic mechanism of organic/inorganic composite electrolytes, inorganic fillers and polymer materials is still unclear.  How to disperse inorganic particles evenly in polymer matrix also needs to be further solved. Designing new composite structure and constructing good electrode/electrolyte interface will be the focus of future research.  

In situ synthesis is an effective means to improve the solid-state electrolyte/electrode interface, improve performance and simplify the process, and provides a greater hope for the large-scale lithium sulfur battery.   

In order to better promote the development of high-performance solid-state lithium battery, it is necessary to build an integrated solid-state lithium sulfur battery with composite electrolyte/interface modification layer/electrode as a whole. The focus is on building a tight, solid layer of interface polish.  Therefore, in situ construction of electrolyte/electrode interface modification layer is an important method to further improve the performance of lithium-sulfur battery. In addition, while improving the performance of solid-state lithium-ion batteries, the mechanism should be thoroughly analyzed to promote the development of new solid-state electrolytes. To achieve large-scale preparation and application of the next generation of high energy density solid lithium sulfur batteries.