【21th.Mar.】Polymer precursors to ion conducting glasses (i.e. LiPON) for thin films, adhesives, binders, and sintering aids towards all solid-state Li-S batteries.
日期：2019-03-21
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Title：Polymer precursors to ion conducting glasses (i.e. LiPON) for thin films, adhesives, binders, and sintering aids towards all solid-state Li-S batteries.
Speaker: Prof. Richard M. Laine, Dept. of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109-2136. talsdad@umich.edu
Time: 03/21/2019, Thursday, 14:00 PM
Location: Chemistry building A, Room 518
Host: Prof. Jun Yang & Linsen Li
Abstract:
Thin ceramic film electrolytes (10-50 µm) offer the potential to eliminate liquid electrolytes in lithium and sodium ion batteries. They also hold promise for assembling all solid-state batteries (ASBs). However, those that offer Li+ conductivities equal to liquid systems (0.1-5 mS/cm/25°C) suffer from other problems. For example, in LATP, Ti4+ and Ge4+ can be irreversibly reduced on cycling. For c-LLZO, dendrites can grow along grain boundaries causing short circuits. Circumvention of these problems arrives in the form of glassy thin films such as LiPON. Unfortunately, amorphous LiPON has conductivities of 10-2-10-4 mS/cm and is best used as very thin (10-100 nm) films applied to LATP or LLZO typically using gas phase deposition methods that are often energy and equipment intensive.
In the assembly of all solid-state batteries a further problem arises when one wants to mate individual components (anode/electrolyte/cathode) uniformly in the assembly of ASBs especially if each component does not have a perfectly flat surface. Neither are there methods of ensuring effective contact between all surfaces providing efficient ion transport.
Polymer precursors appear to offer multiple solutions to these problems. First, they can be applied to ceramic electrolytes/cathode/anode materials as a coating and heated to transform them to the ion conducting phase without needing gas phase application methods. Second, they can be applied directly to surfaces to be mated to form an interface that on heating bonds both surfaces. In this presentation, we discuss methods of synthesizing and employing LiPON polymer precursors to form protective coatings on a variety of ceramic thin films. We also use them as joining aids and finally we discuss their utility for forming all solid state Li-S batteries.
Work supported by DOE Batt500 and Mercedes-Benz.
Bio:
Major research areas for the Laine group include the synthesis and processing of inorganic and organometallic hybrid polymers and nano-oxide powders. Research in the hybrid area emphasizes the synthesis and characterization of nanobuilding blocks based on polyfunctional octahedral (octafunctional) and dodecahederal (dodecafunctional) silsesquioxanes (POSS) and nanocomposites therefrom wherein the periodicity and ordering of the inorganic and organic components are completely defined on a nanometer length scale. To date, POSS nanocomposites made include both aliphatic and aromatic epoxy resins, imides, amides, esters and simple hydrocarbon systems. Related work involves the synthesis of polyfunctional POSS with novel photonic or electronic properties.
Research in the nano-oxide powder area emphasizes the direct synthesis of single and mixed-metal oxide nanopowders by flame spray pyrolysis of mixed-metal metallo-organics. The resulting powders are characterized for their structural, catalytic (energy conversion in particular) and photonic applications. The effects of processing conditions on the catalytic, photonic and structural properties are of primary interest.
