Structuring of Bulk Silicon Particles for Lithium-Ion Battery Applications

Bang, Byoung-Man; Kim, Hyun-Jung; Park, Soo-Jin

doi:2011.2.3.157

J. Electrochem. Sci. Technol > Volume 2(3); 2011 > Article

Article

Journal of Electrochemical Science and Technology 2011;2(3):157-162.
DOI: https://doi.org/10.5229/JECST.2011.2.3.157

Structuring of Bulk Silicon Particles for Lithium-Ion Battery Applications

Byoung-Man Bang, Hyun-Jung Kim, Soo-Jin Park

Interdisciplinary School of Green Energy, Ulsan National Institute of Science and Technology (UNIST);Interdisciplinary School of Green Energy, Ulsan National Institute of Science and Technology (UNIST);Interdisciplinary School of Green Energy, Ulsan National Institute of Science and Technology (UNIST);

Abstract

We report a simple route for synthesizing multi-dimensional structured silicon anode materials from commercially available bulk silicon powders via metal-assisted chemical etching process. In the first step, silver catalyst was deposited onto the surface of bulk silicon via a galvanic displacement reaction. Next, the silver-decorated silicon particles were chemically etched in a mixture of hydrofluoric acid and hydrogen peroxide to make multi-dimensional silicon consisting of one-dimensional silicon nanowires and micro-scale silicon cores. As-synthesized silicon particles were coated with a carbon via thermal decomposition of acetylene gas. The carbon-coated multi-dimensional silicon anodes exhibited excellent electrochemical properties, including a high specific capacity (1800 mAh/g), a stable cycling retention (cycling retention of 89% after 20 cycles), and a high rate capability (71% at 3 C rate, compared to 0.1 C rate). This process is a simple and mass-productive (yield of 40-50%), thus opens up an effective route to make a high-performance silicon anode materials for lithiumion batteries.

Key Words: Bulk silicon, Chemical etching, Structuring of silicon, Lithium ion battery