Multiple performance enhancements with one effect: Improving the electrochemical performance of SiOx coated with specific aromatic compounds

초록

In this study, modification is performed with pyrolyzed fuel oil to analyze the constituent components of petroleum residue oil (PRO), and carbon coating are performed on SiOx surfaces through vapor deposition to determine the effects of the aromatic compounds from the PRO. The effects of the carbon-coating from PRO on the electrochemical performance of a lithium-ion battery are also examined. Carbon-coating layers with amorphous structures and thicknesses of 13.8 to 24.6 nm are obtained depending on the deposition temperature. After 50cycles, the coulombic efficiency of the sample is 99.8 %, the initial cycle capacity is 1095.4 mAh/g at a current density of 1.0C. The rate test results for this sample showing a capacity of 417.4 mAh/g at a current density of 2.0C. This is attributing to the formation of a thick carbon-coating layer on the sample's surface, which maintaining the stability of the sample's structure and suppressing volume expansion. The impedance of this sample also shows the lowest resistance at 189.2 Ω, indicating a better electrochemical performance compared to those of the others. Since 250 PRO contains more 2,3-cycle aromatic compounds than other samples, it is much easier to form the poly-aromatic compound when forming the carbon coating layer of SiOx, thereby improving electrical conductivity and lithium ion diffusion. © 2022 The Korean Society of Industrial and Engineering Chemistry

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