UCLA

In the domain of modern lithium-ion batteries, the anode material plays a critical role in ensuring safe and reliable storage of the battery's capacity for efficient rechargeability. However, the commercial graphite material currently utilized is constrained by its limited volumetric and gravimetric capacity, as well as its proximity to Li plating hazards. With the growing demand for increased energy storage capacity and power density, there is a significant focus on exploring new electrode materials that offer higher specific and areal capacity, scalable synthesis methods, faster charging capabilities, improved safety standards, stable cycling performance, and lower cost. Also, with the development of microscopic techniques, the knowledge gap between battery performance and microscopic changings in cell configuration, such as solid-electrolyte interphase, can be further investigated. This works aims to explore the relevant criteria through the examination of surface-modified (graphitic carbon coated) silicon as a potential anode material and the investigation of a multifunctional solid electrolyte interface (SEI) as a solid-state electrolyte. The primary objective is to advance the understanding of these key components and their interactions, ultimately driving innovation in the field of high-performance batteries. Throughout this thesis, the cyclability of bare Si anode is improved and the electrochemical properties of SEI can be quantitatively measured and correlated to battery performance.