Preparation of Silicon-Carbon-Graphene Composites and their Application to Lithium Ion Secondary Battery

Sun Kyung Kim ； ChanMi Kim ； Hankwon Chang ； Hee Dong Jang

《Aerosol and Air Quality Research》 22卷3期 (2022/03) Pp. 1-10

https://doi.org/10.4209/aaqr.220009

摘要

Recently, high electrochemical performance anode materials for lithium ion secondary batteries are of interest. Here, we present silicon-carbon-graphene (Si-C-GR) composites for high performance anode materials of lithium ion secondary battery (LIB). Aerosol process and heat-treatment were employed to prepare the Si-C-GR composites using a colloidal mixture of silicon, glucose, and graphene oxide (GO) precursor. Fabrication of the Si-C-GR composites was composed of two stages. The first stage was formation of Si-glucose-GO composites by co-assembly of Si and GO while the sprayed droplets of the colloidal mixture went through the pre-heated aerosol reactor, and the second stage was carbonization of glucose and thermal reduction of GO by heat treatment. Morphology of as-fabricated Si-C-GR composites was generally the shape of a crumpled paper ball and the Si particles were well wrapped in carbon and graphene. The effects of the size of the silicon particles in Si-C-GR composites on the material properties including the morphology and crystal structure were investigated. Silicon particles ranged from 50 nm to 1 μm in average diameter were employed while concentration of silicon, graphene oxide and glucose was fixed in the aerosol precursor. The size range of composites was about from 2.2 to 2.9 μm. The composites including silicon particles larger than 200 nm in size exhibited higher performance as LIB anodes such as capacity and coulombic efficiency than silicon particles less than 100 nm, which were about 1500 mAh g^(-1) at 100 cycles in capacity and 99% in coulombic efficiency, respectively.

關鍵字

Aerosol process ； Lithium ion battery (LIB) ； Anode materials ； Silicon-carbon-graphene (Si-C-GR) composites