Insights into the Interfacial Instability between Carbon-Coated SiO Anode and Electrolyte in Lithium-Ion Batteries
RIS ID
136136
Abstract
Carbon-coated SiO is the most promising alternative to the graphite anode for improving the energy density of currently commercialized lithium-ion batteries but exhibits poor cyclic stability that leaves an unclear mechanism. To address this issue, the surface properties of commercial carbon-coated silicon monoxide are investigated in a 1.0 M LiPF6-dimethyl carbonate electrolyte with and without ethylene carbonate (EC), with a comparison of graphite. Unlike graphite that can work well in the electrolytes with and without EC during initial 30 cycles, carbon-coated SiO suffers a serious capacity decay, especially in the electrolyte without EC. By identifying the samples after various cycles, it is found that a relatively stable interphase that makes graphite work well cannot be built on carbon-coated SiO. The chemical analyses demonstrate that there is a strong interaction between SiO with hydrofluoric acid in the electrolyte, which leads to destruction of the carbon-coating layer and prevents the formation of a protective interphase.
Publication Details
Lin, Z., Li, J., Huang, Q., Xu, K., Fan, W., Yu, L., Xia, Q. & Li, W. (2019). Insights into the Interfacial Instability between Carbon-Coated SiO Anode and Electrolyte in Lithium-Ion Batteries. The Journal of Physical Chemistry C: Energy Conversion and Storage, Optical and Electronic Devices, Interfaces, Nanomaterials, and Hard Matter, 123 (20), 12902-12909.