Effects of fluorination on crystal structure and electrochemical performance of antiperovskite solid electrolytes  

作　　者：Lei Gao Manrong Song Ruo Zhao Songbai Han Jinlong Zhu Wei Xia Juncao Bian Liping Wang Song Gao Yonggang Wang Ruqiang Zou Yusheng Zhao 

机构地区：[1]School of Materials Science and Engineering,Peking University,Beijing 100871,China [2]Guangdong Provincial Key Laboratory of Energy Materials for Electric Power,Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and Devices,Academy for Advanced Interdisciplinary Studies,Southern University of Science and Technology,Shenzhen 518055,Guangdong,China [3]Institute for Advanced Study,Shenzhen University,Shenzhen 518055,Guangdong,China

出　　处：《Journal of Energy Chemistry》2023年第2期521-528,I0013,共9页能源化学（英文版）

基　　金：supported by the National Key Research and Development Program of China(2020YFA0210701);the National Natural Science Foundation of China(22005134,12275119,U22A20439);the Shenzhen Science and Technology Program(RCBS20210609103647030);the Guangdong Basic and Applied Basic Research Foundation(2021A1515012403);the Shenzhen Science and Technology Program(KQTD20200820113047086);the Guangdong-Hong Kong-Macao Joint Laboratory for PhotonicThermal-Electrical Energy Materials and Devices(2019B121205001);the open research fund of Songshan Lake Materials Laboratory(2022SLABFK04)。

摘　　要：The development of all-solid-state lithium batteries(ASSLBs)depends on exploiting solid-state electrolytes(SSEs)with high ionic conductivity and electrochemical stability.Fluorination is generally considered to be an effective strategy to improve the ionic conductivity and electrochemical stability of inorganic SSEs.Here,we report the partial fluorination of the chlo rine sites in an antiperovskite,by which the orthorhombic Li_(2)OHCl was transformed into cubic Li_(2)OHCl_(0.9)F_(0.1),resulting in a fourfold increase in ionic conductivity at 30℃.The ab initio molecular dynamics simulations suggest that both the crystal symmetry and the anions electronegativity influence the diffusion of Li+in the antiperovskite structure.Besides,from the perspective of experiments and calculations,it is confirmed that fluorination is a feasible method to improve the electrochemical stability of antiperovskite SSEs.The LiFePO_(4)|Li cell based on Li_(2)OHCl_(0.9)F_(0.1) is also assembled and exhibits stable cycle performance,which indicates that fluorination of antiperovskite SSEs is an effective way to produce high-performance SSEs for practical application of ASSLBs.

关 键 词：ANTIPEROVSKITE Solid-state electrolyte FLUORINATION Ionic conductivity 

分 类 号：TB34[一般工业技术—材料科学与工程] TM912[电气工程—电力电子与电力传动]