What are the problems facing the real application of lithium-sulfur batteries?

The advantages of lithium-sulfur batteries are very obvious: they have a very high theoretical capacity; there is no oxygen in the material, and no oxygen evolution reaction occurs, so the safety performance is good; sulfur resources are abundant and the price of elemental sulfur is extremely low; it is environmentally friendly and has low toxicity. However, the real application of lithium-sulfur batteries still faces some problems, including: (1) Poor conductivity and lithium conductivity: The sulfur molecules in elemental sulfur are connected by 8 S to form a crown of S8, which is a typical electronic and ion insulator. Its electrical conductivity at room temperature is only 5×10-30S/cm. And the products Li2S2 and Li2S are also electronic insulators. Therefore, the utilization rate of the active material is not high, and the rate performance is not good. At present, it is important to prepare small-size sulfur-carbon composite materials to solve the problems of conductivity and lithium conductivity of lithium-sulfur battery cathode materials. (2) Lithium polysulfide shuttle effect: During the charging and discharging process of lithium-sulfur batteries, long-chain lithium polysulfide Li2Sx (4