石榴石Li7La3Zr2O12固态电解质电导率优化策略研究进展.

In recent years, the drawbacks of liquid lithium-ion batteries (LIBs) with carbon anodes and organic electrolytes have become more and more obvious. Safety accidents such as electrolyte leakage and overheating combustion occur frequently. In addition, traditional LIBs are unable to meet the demand for high energy density batteries as modern society develops. Due to many disadvantages mentioned above, there is an urgent need to develop a new type of battery that combines high energy density with high safety performance. Introducing a solid electrolyte was found to achieve this. Solid lithium-ion batteries (SSLBs) have higher energy density, wider operating temperature range, and higher safety level than traditional liquid ones. As one of the core materials of solid-state batteries, solid electrolyte is critical to battery performance. Garnet Li7La3Zr2O12 has high Li+ conductivity (1×10-4 ~1×10-3 S/cm), wide electrochemical window (9 V), and good stability with lithium anodes. Based on these advantages, LLZO stands out among many types of solid-state electrolytes. In this article, the improvements of ionic conductivity in garnet-type solid electrolyte are summarized. Firstly, the crystal structure of LLZO as well as the relationship between structure and conductivity is discussed. Then, three methods for improving lithium ions conductivity are reviewed, including doping element, improving sintering techniques, and adding additives. Finally, several remaining challenges for the future development of garnet-based solid state batteries are presented, which can be used as a reference for related research. [ABSTRACT FROM AUTHOR]