The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining...The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining good ion diffusion through optimized electrode tortuosity.However,conventional thick electrodes increase ion diffusion length and cause larger ion concentration gradients,limiting reaction kinetics.We demonstrate a strategy for building interpenetrated structures that shortens ion diffusion length and reduces ion concentration inhomogeneity.This free-standing device structure also avoids short-circuiting without needing a separator.The feature size and number of interpenetrated units can be adjusted during printing to balance surface area and ion diffusion.Starting with a 3D-printed interpenetrated polymer substrate,we metallize it to make it conductive.This substrate has two individually addressable electrodes,allowing selective electrodeposition of energy storage materials.Using a Zn//MnO_(2) battery as a model system,the interpenetrated device outperforms conventional separate electrode configurations,improving volumetric energy density by 221%and exhibiting a higher capacity retention rate of 49%compared to 35%at temperatures from 20 to 0℃.Our study introduces a new EESD architecture applicable to Li-ion,Na-ion batteries,supercapacitors,etc.展开更多
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
We report an efficient phase field formalism to compute the stress distribution in polycrystalline materials with arbitrary elastic inhomogeneity and anisotropy.The dependence of elastic stiffness tensor on grain orie...We report an efficient phase field formalism to compute the stress distribution in polycrystalline materials with arbitrary elastic inhomogeneity and anisotropy.The dependence of elastic stiffness tensor on grain orientation is taken into account,and the elastic equilibrium equation is solved using a spectral iterative perturbation method.We discuss its applications to computing residual stress distribution in systems containing arbitrarily shaped cavities and cracks(with zero elastic modulus)and to determining the effective elastic properties of polycrystals and multilayered composites.展开更多
基金financial support from the Center for Coastal Climate Resilience of the University of California,Santa Cruz(UCSC)This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under Contract No.DE-AC52-07NA27344 and supported by Laboratory Directed Research and Development award 23-SI-002.IM release number:LLNL-JRNL-862347。
文摘The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining good ion diffusion through optimized electrode tortuosity.However,conventional thick electrodes increase ion diffusion length and cause larger ion concentration gradients,limiting reaction kinetics.We demonstrate a strategy for building interpenetrated structures that shortens ion diffusion length and reduces ion concentration inhomogeneity.This free-standing device structure also avoids short-circuiting without needing a separator.The feature size and number of interpenetrated units can be adjusted during printing to balance surface area and ion diffusion.Starting with a 3D-printed interpenetrated polymer substrate,we metallize it to make it conductive.This substrate has two individually addressable electrodes,allowing selective electrodeposition of energy storage materials.Using a Zn//MnO_(2) battery as a model system,the interpenetrated device outperforms conventional separate electrode configurations,improving volumetric energy density by 221%and exhibiting a higher capacity retention rate of 49%compared to 35%at temperatures from 20 to 0℃.Our study introduces a new EESD architecture applicable to Li-ion,Na-ion batteries,supercapacitors,etc.
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.
基金The authors would like to acknowledge the financial supports from the National Science Foundation under the grant number DMR-0710483.
文摘We report an efficient phase field formalism to compute the stress distribution in polycrystalline materials with arbitrary elastic inhomogeneity and anisotropy.The dependence of elastic stiffness tensor on grain orientation is taken into account,and the elastic equilibrium equation is solved using a spectral iterative perturbation method.We discuss its applications to computing residual stress distribution in systems containing arbitrarily shaped cavities and cracks(with zero elastic modulus)and to determining the effective elastic properties of polycrystals and multilayered composites.
