| AVS 55th International Symposium & Exhibition | |
| In Situ Microscopy and Spectroscopy: Interfacial and Nanoscale Science Topical Conference | Thursday Sessions |
| Session IS+NS+TR+NC-ThM |
| Session: | In Situ Spectroscopy – Dynamic Nanoscale Processes |
| Presenter: | C.M. Wang, Pacific Northwest National Laboratory |
| Authors: | C.M. Wang, Pacific Northwest National Laboratory Z.G. Yang, Pacific Northwest National Laboratory S. Thevuthasan, Pacific Northwest National Laboratory J. Liu, Pacific Northwest National Laboratory D.R. Baer, Pacific Northwest National Laboratory N. Salmon, Hummingbirds Scientific |
| Correspondent: | Click to Email |
Repeated charging and discharging of a Li-ion battery induces microstructural evolutions both at the interface between the electrolyte and the electrode and within the electrode (active materials) due to Li migration. Although it has been established that this structural evolution is responsible for the failure of such batteries, the mechanisms of the microstructural evolution as a function of charging/discharging are not well understood. Advanced diagnostic tools such as electron microscopy along with other surface and bulk sensitive tools, usually in ex-situ mode, have been used to probe into this scientific issue. However, it has been realized that characterizing this interface using an ex-situ capability is a challenge as the materials will be altered during sample preparation and processing and the interface will be stable only under the operating conditions. In-situ capabilities that enable the observation of the structural and chemical changes during the dynamic operation of battery are needed to address this scientific and technological challenge. We have been developing an environmental holder capability for TEM, trying to gain fundamental scientific understanding of the chemical and structural evolution at the interface between the electrolyte and the electrode as well as within the electrodes under the dynamic operation conditions of the Li battery system. In the preliminary research work, we have explored the interface change using TiO2 nanowire as the anode material. Transmission electron microscopy (TEM) imaging, electron diffraction, and electron energy-loss spectroscopy (EELS) were used to probe into these structural evolutions during the operation of the battery.