Although multiple oxide-based solid electrolyte materials with intrinsically high ionic conductivities have emerged,practical processing and synthesis routes introduce grain boundaries and other interfaces that can pe...Although multiple oxide-based solid electrolyte materials with intrinsically high ionic conductivities have emerged,practical processing and synthesis routes introduce grain boundaries and other interfaces that can perturb primary conduction channels.To directly probe these effects,we demonstrate an efficient and general mesoscopic computational method capable of predicting effective ionic conductivity through a complex polycrystalline oxide-based solid electrolyte microstructure without relying on simplified equivalent circuit description.We parameterize the framework for Li_(7-x)La_(3)Zr_(2)0_(12)(LLZO)gamet solid electrolyte by combining synthetic microstructures from phase-field simulations with diffusivities from molecular dynamics simulations of ordered and disordered systems.Systematically designed simulations reveal an interdependence between atomistic and mesoscopic microstructural impacts on the effective ionic conductivity of polycrystalline LLZO,quantified by newly defined metrics that characterize the com plex ionic transport mechanism.Our results provide fundamental understanding of the physical origins of the reported variability in ionic conductivities based on an extensive analysis of literature data,while simultaneously outlining practical design guidance for achieving desired ionic transport properties based on conditions for which sensitivity to microstructural features is highest.Additional implications of our results are discussed,including a possible connection between ion conduction behavior and dendrite formation.展开更多
基金This work was performed under the auspices of the U.S.Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344The authors acknowledge financial support from the U.S.Department of Energy(DOE),Office of Energy Efficiency and Renewable Energy,Vehicle Technologies Office,through the Battery Materials Research program.This work was partially funded by the Laboratory Directed Research and Development Program at LLNL under the project tracking code 15-ERD-022 and 18-FS-019.Additional computing support came from the LLNL Institutional Computing Grand Challenge program.The work of A.Grieder and N.Adelstein was supported by the National Science Foundation under Grant No.DMR-1710630 and simulations utilized the Extreme Science and Engineering Discovery Environment(XSEDE)83 Stampede2 at the University of Texas,Austin through allocation DMR180033.Work at The Pennsylvania State University is partially supported by the Donald W.Hamer Foundation through a Hamer Professorship.Helpful discussions about experimental microstructures of solid electrolytes with J.Ye(LLNL)are acknowledged.
文摘Although multiple oxide-based solid electrolyte materials with intrinsically high ionic conductivities have emerged,practical processing and synthesis routes introduce grain boundaries and other interfaces that can perturb primary conduction channels.To directly probe these effects,we demonstrate an efficient and general mesoscopic computational method capable of predicting effective ionic conductivity through a complex polycrystalline oxide-based solid electrolyte microstructure without relying on simplified equivalent circuit description.We parameterize the framework for Li_(7-x)La_(3)Zr_(2)0_(12)(LLZO)gamet solid electrolyte by combining synthetic microstructures from phase-field simulations with diffusivities from molecular dynamics simulations of ordered and disordered systems.Systematically designed simulations reveal an interdependence between atomistic and mesoscopic microstructural impacts on the effective ionic conductivity of polycrystalline LLZO,quantified by newly defined metrics that characterize the com plex ionic transport mechanism.Our results provide fundamental understanding of the physical origins of the reported variability in ionic conductivities based on an extensive analysis of literature data,while simultaneously outlining practical design guidance for achieving desired ionic transport properties based on conditions for which sensitivity to microstructural features is highest.Additional implications of our results are discussed,including a possible connection between ion conduction behavior and dendrite formation.
