Defect chemistry engineering of Ga-doped garnet electrolyte with high stability for solid-state lithium metal batteries  

作　　者：陈思汗 黎俊 刘可可 孙笑晨 万京伟 翟慧宇 唐新峰 谭刚健 Sihan Chen;Jun Li;Keke Liu;Xiaochen Sun;Jingwei Wan;Huiyu Zhai;Xinfeng Tang;Gangjian Tan(State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China;International School of Materials Science&Engineering,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China [2]International School of Materials Science&Engineering,Wuhan University of Technology,Wuhan 430070,China

出　　处：《Chinese Physics B》2024年第8期560-567,共8页中国物理B（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Grant No.52171221);the National Key Research and Development Program of China (Grant No.2019YFA0704900)。

摘　　要：Ga-doped Li_(7)La_(3)Zr_(2)O_(12)(Ga-LLZO)has long been considered as a promising garnet-type electrolyte candidate for all-solid-state lithium metal batteries(ASSLBs)due to its high room temperature ionic conductivity.However,the typical synthesis of Ga-LLZO is usually accompanied by the formation of undesired LiGaO_(2) impurity phase that causes severe instability of the electrolyte in contact with molten Li metal during half/full cell assembly.In this study,we show that by simply engineering the defect chemistry of Ga-LLZO,namely,the lithium deficiency level,LiGaO_(2) impurity phase is effectively inhibited in the final synthetic product.Consequently,defect chemistry engineered Ga-LLZO exhibits excellent electrochemical stability against lithium metal,while its high room temperature ionic conductivity(~1.9×10^(-3)S·cm^(-1))is well reserved.The assembled Li/Ga-LLZO/Li symmetric cell has a superior critical current density of 0.9 mA·cm^(-2),and cycles stably for 500 hours at a current density of 0.3 mA·cm^(-2).This research facilitates the potential commercial applications of high performance Ga-LLZO solid electrolytes in ASSLBs.

关 键 词：Ga-doped Li_7La_3Zr_2O_(12)(Ga-LLZO) defect chemistry engineering high room temperature ionic conductivity electrochemical stability 

分 类 号：TM912[电气工程—电力电子与电力传动]