Li_(7)La_(3)Zr_(2)O_(12)(LLZO)is considered as a promising solid-state electrolyte due to its high ionic conductivity,wide electrochemical window,and excellent electrochemical stability.However,its application in soli...Li_(7)La_(3)Zr_(2)O_(12)(LLZO)is considered as a promising solid-state electrolyte due to its high ionic conductivity,wide electrochemical window,and excellent electrochemical stability.However,its application in solid-state lithium metal batteries(SSLMBs)is impeded by the growth of lithium dendrites in LLZO due to some reasons such as its high electronic conductivity.In this study,lithium fluoride(LiF)was introduced into Ta-doped LLZO(LLZTO)to modify its grain boundaries to enhance the performance of SSLMBs.A nanoscale LiF layer was uniformly coated on the LLZTO grains,creating a threedimensional continuous electron-blocking network at the grain boundaries.Benefiting from the electronic insulator LiF and the special structure of the modified LLZTO,the symmetric cells based on LLZO achieved a high critical current density(CCD)of 1.1 mA·cm^(-2)(in capacity-constant mode)and maintained stability over 2000 h at 0.3 mA·cm^(-2).Moreover,the full cells combined with a LiFePO_(4)(LFP)cathode,demonstrated excellent cycling performance,retaining 97.1% of capacity retention after 500 cycles at 0.5 C.Therefore,this work provides a facile and effective approach for preparing a modified electrolyte suitable for high-performance SSLMBs.展开更多
基金supported by the National Natural Science Foundation of China(No.52202231)the Natural Science Foundation of Hubei Province(No.2023AFB316)+1 种基金the Independent Innovation Projects of the Hubei Longzhong Laboratory(No.2022ZZ-16)the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology)(No.2022-KF-23).
文摘Li_(7)La_(3)Zr_(2)O_(12)(LLZO)is considered as a promising solid-state electrolyte due to its high ionic conductivity,wide electrochemical window,and excellent electrochemical stability.However,its application in solid-state lithium metal batteries(SSLMBs)is impeded by the growth of lithium dendrites in LLZO due to some reasons such as its high electronic conductivity.In this study,lithium fluoride(LiF)was introduced into Ta-doped LLZO(LLZTO)to modify its grain boundaries to enhance the performance of SSLMBs.A nanoscale LiF layer was uniformly coated on the LLZTO grains,creating a threedimensional continuous electron-blocking network at the grain boundaries.Benefiting from the electronic insulator LiF and the special structure of the modified LLZTO,the symmetric cells based on LLZO achieved a high critical current density(CCD)of 1.1 mA·cm^(-2)(in capacity-constant mode)and maintained stability over 2000 h at 0.3 mA·cm^(-2).Moreover,the full cells combined with a LiFePO_(4)(LFP)cathode,demonstrated excellent cycling performance,retaining 97.1% of capacity retention after 500 cycles at 0.5 C.Therefore,this work provides a facile and effective approach for preparing a modified electrolyte suitable for high-performance SSLMBs.
