Dresden 2017 – wissenschaftliches Programm
MM 50: SYLI: Symposium Interfacial Challenges in Solid-State Li Ion Batteries - Structure - property relationships II
MM 50.3: Vortrag
Mittwoch, 22. März 2017, 16:15–16:30, IFW D
Polycrystalline NaxCoO2 thin films on ß-Alumina ceramics for solid state batteries — •Philipp Kehne1, Conrad Guhl2, René Hausbrand2, and Philipp Komissinskiy1 — 1Department of Materials Science, TU-Darmstadt, Advanced thin film technology — 2Department of Materials Science, TU-Darmstadt, Surface science
Good cycling performance was previously shown for rechargeable sodium ion batteries with layered-oxide cathode materials such as NaxCoO2 in combination with liquid electrolytes. However, studies of sodium-based solid state batteries are necessary to correlate the electronic structure of sodium-ion insertion materials with the battery performance. Here we report polycrystalline NaxCoO2 films grown on ß-Alumina polycrystalline ceramic substrates with pulsed laser deposition. The sodium content in the films can be adjusted in the range of x = 0.6 * 1.1 by varying the post-deposition annealing conditions. The ß-alumina substrates reveal ionic conductivities of 0.002 S/cm (25 ∘C) and can be used as electrolyte in solid-state sodium batteries. The fabricated Swagelok-type rechargeable batteries with NaxCoO2 thin-film cathodes, ß-alumina electrolyte, and sodium anodes reveal an open circuit voltage of 2.75 V and a specific capacitance of C = 80 mAh/g. Investigations of the electronic structure of the materials and interfaces in the fabricated batteries by in-situ XPS are in progress.