Transformation of Undesired Li_(2)CO_(3)into Lithiophilic Layer Via Double Replacement Reaction for Garnet Electrolyte Engineering

作     者：Jiaxu Zhang Ruohan Yu Jun Li Huiyu Zhai Gangjian Tan Xinfeng Tang Jiaxu Zhang;Ruohan Yu;Jun Li;Huiyu Zhai;Gangjian Tan;Xinfeng Tang

作者机构：State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070China International School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China 

出 版 物：《Energy & Environmental Materials》 (能源与环境材料（英文）)

年 卷 期：2022年第5卷第3期

页      面：962-968页

核心收录：

学科分类：0710[理学-生物学] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 0808[工学-电气工程] 081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 0807[工学-动力工程及工程热物理] 0815[工学-水利工程] 

基　　金：financial support from the National Natural Science Foundation of China(Grant No.11804261) National Key Research and Development Program of China(Grant No.2019YFA0704900)。 

主　　题：double replacement reaction garnet electrolytes lithiophilic layer solid-state lithium batteries 

摘      要：Garnet-type solid-state electrolytes(SSEs)are a remarkable Li-ion electrolyte for the realization of next-generation all-solid-state lithium batteries due to their excellent stability against Li metal as well as high ionic conductivities at room temperature.However,garnet electrolytes always contain undesired and hardly removable Li_(2)CO_(3) contaminations that have persistently large resistance and unstable interface contact with Li metal.This is a critical bottleneck for the practical application of garnet electrolytes.Here,we design a novel strategy to completely root out Li_(2)CO_(3) both inside and on the surface of garnet.This is achieved by a so-called double replacement reaction between Li_(2)CO_(3) and SiO_(2) during one-step hot press process for garnet electrolyte densification.It leads to in-situ transformation of LixSiOy(LSO)mostly locating around the grain boundaries of garnet.Due to the higher ion conductivity and better electrochemistry stability of LSO than Li_(2)CO_(3),the modified garnet electrolyte shows much improved electrochemical performance.Moreover,the wettability between modified garnet electrolyte and lithium metals was significantly enhanced in the absence of surface Li_(2)CO_(3).As a proof of concept,an assembled Li symmetric cell with modified garnet electrolyte displays a high critical current density(CCD)of 0.7 mA cm^(-2)and a low interfacial impedance(5Ωcm^(2))at 25℃.These results indicate that the upcycling of Li_(2)CO_(3)is a promising strategy to well-address the degradation and interfacial issue associated with garnet electrolytes.