Wednesday, 4 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
The interface of electrode materials in contact with solid-state electrolytes is of current interest for the development of devices with high energy density and good safety. In-situ transmission electron microscopy (TEM) of energy storage materials allows for the detailed study of structure-property relationships near solid interfaces during electrochemical charge and discharge. Here, we will describe the design of an in-situ TEM platform to investigate the structure-property relationship of a model energy storage oxide, V2O5, in contact with a state-of-the-art solid-state electrolyte Li7La3Zr2O12 (LLZO). The cell was fabricated by the atomic layer deposition (ALD) of V2O5 (~ 50 nm thick) onto the electrolyte and subsequent focused ion beam (FIB) milling and lift-out of a micron-long electrode/electrolyte architecture. The lithium metal anode was electrochemically deposited directly onto the gold electrode of an in-situ TEM chip. Assembly of the electrochemical cell was performed in a scanning electron microscope using a micromanipulator. Bright-field TEM and electron energy loss spectroscopy (EELS) showed that the deposited V2O5 layer formed a well-defined interface with LLZO and this allowed for the determination of the vanadium oxidation state. This work demonstrates the fabrication of a platform for the in-situ TEM study of materials at electrode/solid-state electrolyte interfaces that can readily be adapted to other types of solid state battery chemistries.