Date: July 19, 2019 ǀ 14:00-15:00
Location: Auditorium, TUM Institute for Advanced Study, Lichtenbergstrasse 2 a, 85748 Garching, Tel +49.89.289.10550
Organization: TUM-IAS and Rudolf Diesel Industry Fellow Dr. Filippo Maglia (BMW Group)
Admission is free. No registration required.
Title: Beyond Dendrites, Cycling Li-Metal Across Garnet at High Current Densities.
Speaker: Prof. Eric D. Wachsman, Maryland Energy Innovation Institute, University of Maryland, College Park, MD, USA; Ion Storage Systems, College Park, MD, USA. (ewach@umd.edu).
Dr. Eric D Wachsman is CEO of Ion Storage Systems, and Director of the Maryland Energy Innovation Institute and Crentz Centennial Chair in Energy Research at the University of Maryland. He is Vice President of The Electrochemical Society (ECS), a Fellow of both ECS and the American Ceramic Society, World Academy of Ceramics member, Editor-in-Chief of Ionics, and on the Editorial Board of Scientific Reports, Energy Systems, and Energy Technology and a member of the American Chemical Society, the International Society for Solid State Ionics, and the Materials Research Society. His research is focused on solid ion-conducting materials and electrocatalysts, and includes the development of solid-state batteries, solid oxide fuel cells, ion-transport membrane reactors, and solid-state gas sensors. He has more than 270 publications and 20 patents on ionic and electronic conducting materials and device performance, and to date three companies have been founded based on these technologies.
Abstract: Solid-state Li-batteries (SSLiBs) have the potential to be a transformational and intrinsically safe energy storage solution. However, their progress has been limited by high solid-solid interfacial impedance and numerous reports of Li-dendrites and a corresponding “critical current density”. By first modifying the garnet surface to enable Li-metal to wet it and then fabricating garnet-electrolytes into tailored tri-layer microstructures to form electrode supported dense thin-film (~10μm) solid-state electrolytes we have been able to overcome these limitations. The microstrucurally tailored porous garnet scaffold support increases electrode/electrolyte interfacial area, overcoming the high impedance typical of planar geometry SSLiBs resulting in an area specific resistance (ASR) of only ~2 to 7 Ωcm-2 at room temperature. The unique garnet scaffold/electrolyte/scaffold structure further allows for charge/discharge of the Li-metal anode and cathode scaffolds by pore-filling, thus providing high depth of discharge ability without mechanical cycling fatigue seen with typical electrodes. Moreover, these scalable multilayer ceramic fabrication techniques, without need for dry rooms or vacuum equipment, provide for dramatically reduced manufacturing cost.
The fabrication of supported dense thin-film garnet electrolytes, their ability to cycle Li-metal at high current densities with no dendrite formation, and results for Li-metal anode/garnet-electrolyte based batteries with a number of different cathode chemistries will be presented.