Research Progress of Solid Electrolytes in Lithium Batteries

With the continuous advancement of sustainable energy and the increasing demand for high-energy-density batteries, lithium-ion batteries have received much attention. However, lithium-ion batteries have problems such as leakage, short cycle life, and Lithium Dendrite Growth, which result in low battery safety and hinder their development. To address this issue, this article summarizes and classifies four different types of solid electrolytes, which can fundamentally alleviate safety problems such as thermal runaway. Research shows that oxide-based solid electrolytes have a wider electrochemical window and stronger stability compared to the other three types, making them more conducive to breaking through the limitations in energy density. However, the excessively high cost of this material has severely hindered its commercialization process. Polymer-based electrolytes, on the other hand, possess good flexibility and strong processability, but they are also prone to deformation, which affects the performance of the battery. The oxidative stability of halide electrolytes is good, and they can be matched with high-voltage positive electrode materials. However, their strict preparation conditions increase the operational difficulty and cost, and thus pose significant challenges in practical applications. Finally, the sulfide electrolyte has a high ionic conductivity similar to that of liquid electrolytes. However, the generation of many by-products leads to the problem of unstable interfaces. Additionally, this paper discusses the exploration of new materials and the application of artificial intelligence in the future development of solid electrolytes.