固态电解质锂镧锆氧(LLZO)的研究进展

Recent progress on the Li7La3Zr2O12(LLZO)solid electrolyte

高安全、高能量密度以及长寿命全固态电池被视为下一代最重要的储能技术之一,而开发高性能固态电池的核心之一就是制备性能匹配的固态电解质。石榴石型的Li7La3Zr2O12(LLZO)固态电解质因其高离子电导(室温下约10-3 S/cm)、高电化学稳定性和对正极材料及锂金属负极良好的化学稳定性,自2007年被发现之后,便被认为是颇具前景的一类固态电解质材料。本文系统地综述了LLZO在结构调控、掺杂策略、离子输运机制认识以及界面稳定策略等最新进展;总结了对富锂石榴石结构、快离子输运行为的认识过程;并系统介绍了优化正极/负极与石榴石型固体电解质界面结构,改善界面润湿性的解决思路及LLZO基固态电解质材料构筑固态电池的进展,以期为探索全固态锂离子电池的实际应用提供借鉴。

Solid-state batteries with high safety, high energy density, and long lifespan are considered one of the most important next-generation energy storage technologies to replace traditional organic rechargeable Li-ion batteries. The development of such solid batteries is limited by the solid electrolytes that are compatible with solid-solid interfaces. Since it’s discovered in 2007, the garnet Li7 La3 Zr2 O12(LLZO) solid electrolyte has demonstrated a promising application in solid batteries owing to its superior ionic conductivity(ca. 10-3 S/cm at room temperature) and highly stable chemical/electrochemical activities. Therefore, this review systematically summarizes the recent progress on the structural manipulation, elemental doping, and the fundamentals of fast ionic migration. In addition,this paper introduces an approach to optimize the interface structure between the positive/negative electrodes and the garnet-type solid electrolyte, improve the interface wettability and compatibility with LLZO electrodes, and presents the history of Li-rich garnet solid electrolytes. The new results on the development of high-performance LLZO-based solid batteries are also included to outline the path for building better solid batteries. This paper sheds new light on promoting the practical application of allsolid-state lithium-ion batteries.