Rare-earth(RE)halide solid electrolytes(HSEs)have been an emerging research area due to their good electrochemical and mechanical properties for all-solid-state lithium batteries(ASSBs).However,only very limited types...Rare-earth(RE)halide solid electrolytes(HSEs)have been an emerging research area due to their good electrochemical and mechanical properties for all-solid-state lithium batteries(ASSBs).However,only very limited types of HSEs have been reported with high performance.In this work,tens of grams of RE-HSE Li_(3)TbBr_(6)(LTbB)was synthesized by a vacuum evaporationassisted method.The as-prepared LTbB displays a high ionic conductivity of 1.7 mS·cm^(-1),a wide electrochemical window,and good formability.Accordingly,the assembled solid lithium-tellurium(Li-Te)battery based on the LTbB HSE exhibits excellent cycling stability up to 600 cycles,which is superior to most previous reports.The processes and the chemicals during the discharge/charge of Li-Te batteries have been studied by various in situ and ex situ characterizations.Theoretical calculations have demonstrated the dominant conductivity contributions of the direct[octahedral]-[octahedral]([Oct]-[Oct])pathway for Li ion migrations in the electrolyte.The Tb sites guarantee efficient electron transfer while the Li 2s orbitals are not affected during migration,leading to a low activation barrier.Therefore,this successful fabrication and application of LTbB have offered a highly competitive solution for solid electrolytes in ASSBs,indicating the great potential of RE-based HSEs in energy devices.展开更多
硫化物Li_(3)PS_(4)是重要的含硫快离子导体,锂离子电导率高,机械性能优异,化学兼容性好,属于全固态电池中一类重要的固态电解质.Li_(3)PS_(4)具有多种晶体结构(玻璃态、α相、β相、γ相),而晶体结构对于材料离子电导率有决定性的影响...硫化物Li_(3)PS_(4)是重要的含硫快离子导体,锂离子电导率高,机械性能优异,化学兼容性好,属于全固态电池中一类重要的固态电解质.Li_(3)PS_(4)具有多种晶体结构(玻璃态、α相、β相、γ相),而晶体结构对于材料离子电导率有决定性的影响,因此探究不同Li_(3)PS_(4)晶体结构的合成条件及其转变过程对固态电解质的应用有重要意义.本文通过原位变温Raman和室温X射线衍射(XRD)分析发现,通过球磨法所得glass-Li_(3)PS_(4)在首次升温过程中(240℃)优先转变为亚稳态的β-Li_(3)PS_(4),此时冷却到室温能保持β相结构,并具有较高的离子电导率(0.65 mS cm^(-1)).当烧结温度继续升高(>480℃),β相会转变为离子电导率更高但热力学不稳定的α-Li_(3)PS_(4),在后续的降温过程中,α相会直接转变为热力学更稳定但离子电导率差的γ-Li_(3)PS_(4).此外,γ-Li_(3)PS_(4)和β-Li_(3)PS_(4)具有一定的结构记忆效应,即使经历二次低温烧结后(240℃)也能维持其固有的结构.以上结果表明,首次烧结温度对于Li_(3)PS_(4)材料的结构和离子电导率具有重要的影响,合理控制烧结温度能够成功制备出具有更高离子电导率的β-Li_(3)PS_(4)固态电解质.此外,所制备的β-Li_(3)PS_(4)固态电解质对锂表现出相对优异的界面性能.展开更多
基金This work was supported by the National Key R&D Program of China(No.2021YFA1501101)the Natural Science Foundation of China(No.21971117)+11 种基金Functional Research Funds for the Central Universities,Nankai University(No.63186005)Tianjin Key Lab for Rare Earth Materials and Applications(No.ZB19500202)the National Natural Science Foundation of China/Research Grant Council Joint Research Scheme(No.N_PolyU502/21)111 Project(No.B18030)from ChinaOutstanding Youth Project of Tianjin Natural Science Foundation(No.20JCJQJC00130)Key Project of Tianjin Natural Science Foundation(No.20JCZDJC00650)the Projects of Strategic Importance of The Hong Kong Polytechnic University(No.1-ZE2V)Shenzhen Fundamental Research Scheme-General Program(No.JCYJ20220531090807017)National Postdoctoral Program for Innovative Talents(No.BX20220157)Open Foundation of State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures(No.2022GXYSOF07)Haihe Laboratory of Sustainable Chemical Transformations.B.L.H.also thanks the support from Research Centre for Carbon-Strategic Catalysis(RCCSC),Research Institute for Smart Energy(RISE)Research Institute for Intelligent Wearable Systems(RI-IWEAR)of the Hong Kong Polytechnic University.
文摘Rare-earth(RE)halide solid electrolytes(HSEs)have been an emerging research area due to their good electrochemical and mechanical properties for all-solid-state lithium batteries(ASSBs).However,only very limited types of HSEs have been reported with high performance.In this work,tens of grams of RE-HSE Li_(3)TbBr_(6)(LTbB)was synthesized by a vacuum evaporationassisted method.The as-prepared LTbB displays a high ionic conductivity of 1.7 mS·cm^(-1),a wide electrochemical window,and good formability.Accordingly,the assembled solid lithium-tellurium(Li-Te)battery based on the LTbB HSE exhibits excellent cycling stability up to 600 cycles,which is superior to most previous reports.The processes and the chemicals during the discharge/charge of Li-Te batteries have been studied by various in situ and ex situ characterizations.Theoretical calculations have demonstrated the dominant conductivity contributions of the direct[octahedral]-[octahedral]([Oct]-[Oct])pathway for Li ion migrations in the electrolyte.The Tb sites guarantee efficient electron transfer while the Li 2s orbitals are not affected during migration,leading to a low activation barrier.Therefore,this successful fabrication and application of LTbB have offered a highly competitive solution for solid electrolytes in ASSBs,indicating the great potential of RE-based HSEs in energy devices.
基金supported by the National Natural Science Foundation of China(61071040)Leading Academic Discipline Project of Shanghai Municipal Education Commission,China(J50102)Research and Innovation Project of Shanghai Municipal Education Commission,China~~
文摘硫化物Li_(3)PS_(4)是重要的含硫快离子导体,锂离子电导率高,机械性能优异,化学兼容性好,属于全固态电池中一类重要的固态电解质.Li_(3)PS_(4)具有多种晶体结构(玻璃态、α相、β相、γ相),而晶体结构对于材料离子电导率有决定性的影响,因此探究不同Li_(3)PS_(4)晶体结构的合成条件及其转变过程对固态电解质的应用有重要意义.本文通过原位变温Raman和室温X射线衍射(XRD)分析发现,通过球磨法所得glass-Li_(3)PS_(4)在首次升温过程中(240℃)优先转变为亚稳态的β-Li_(3)PS_(4),此时冷却到室温能保持β相结构,并具有较高的离子电导率(0.65 mS cm^(-1)).当烧结温度继续升高(>480℃),β相会转变为离子电导率更高但热力学不稳定的α-Li_(3)PS_(4),在后续的降温过程中,α相会直接转变为热力学更稳定但离子电导率差的γ-Li_(3)PS_(4).此外,γ-Li_(3)PS_(4)和β-Li_(3)PS_(4)具有一定的结构记忆效应,即使经历二次低温烧结后(240℃)也能维持其固有的结构.以上结果表明,首次烧结温度对于Li_(3)PS_(4)材料的结构和离子电导率具有重要的影响,合理控制烧结温度能够成功制备出具有更高离子电导率的β-Li_(3)PS_(4)固态电解质.此外,所制备的β-Li_(3)PS_(4)固态电解质对锂表现出相对优异的界面性能.
