Publications by authors named "Yeyoung Ha"
Article Synopsis
- The presence of trace amounts of water in silicon-based lithium-ion batteries negatively impacts the electrochemical performance by affecting the formation and properties of the solid electrolyte interphase (SEI).
- The study analyzes the SEI created in a specific electrolyte condition both with and without added water, investigating how changes in water concentration and potential levels influence the SEI's characteristics through various microscopy and spectroscopy methods.
- Findings reveal that additional water leads to undesirable reactions, resulting in an insulating SEI enriched with fluorophosphate and a compromised Si electrode surface, which ultimately hinders battery efficiency.
We present a novel spectroscopic technique for in situ Raman microscopy studies of battery electrodes. By creating nanostructures on a copper mesh current collector, we were able to utilize surface-enhanced Raman spectroscopy (SERS) to monitor the evolution of the silicon anode-electrolyte interphase. The spectra show reversible Si peak intensity changes upon lithiation and delithiation.
View Article and Find Full Text PDFMagnesium batteries offer an opportunity to use naturally abundant Mg and achieve large volumetric capacities reaching over four times that of conventional Li-based intercalation anodes. High volumetric capacity is enabled by the use of a Mg metal anode in which charge is stored via electrodeposition and stripping processes, however, electrolytes that support efficient Mg electrodeposition and stripping are few and are often prepared from highly reactive compounds. One interesting electrolyte solution that supports Mg deposition and stripping without the use of highly reactive reagents is the magnesium aluminum chloride complex (MACC) electrolyte.
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