Different lithium ion conducting garnet-type thin films were prepared by pulsed laser deposition. Of these garnet-type thin films Li6BaLa2Ta2O12, cubic Li6.5La3Zr1.5Ta0.5O12 (additionally stabilized by Al2O3) and cubic Li7La3Zr2O12 stabilized by Ga2O3 were investigated in more detail. Conductivity measurements of these thin films performed in lateral geometry showed total conductivities of 1.7x10 6 Scm 1, 2.9x10 6 Scm 1 and 1.2x10 6 Scm 1, respectively. Electrochemical impedance spectroscopy was performed in axial geometry (orthogonal to the substrate), revealing conductivities of 3.3x10 5 Scm 1 for Li6BaLa2Ta2O12 which is comparable to the bulk conductivity of Li6BaLa2Ta2O12 (4x10 5 Scm 1). The comparatively low lateral conductivity of the garnet-type material could be increased to a maximum of 2.8x10 5 Scm 1 for multilayer structures of two different alternating garnet-type materials (Li6.5La3Zr1.5Ta0.5O12:Al2O3, Li7La3Zr2O12:Ga2O3). These investigations revealed a strong influence of the thin film microstructure on the total conductivity. Additionally the electronic partial conductivity of Li6BaLa2Ta2O12 as bulk and thin film material was determined. The garnet-type thin films were successfully tested as protective coatings and as ion-selective membranes in hybrid battery cells (liquid and solid electrolyte combined in one cell). The ion-selective membranes successfully suppressed the undesired polysulfide shuttle mechanism inside a lithium sulfur battery.
Verknüpfung zu Publikationen oder weiteren Datensätzen
