화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.164, No.9, A2065-A2074, 2017
Effects of Electrolyte Composition and Voltage Scan Rate on Cyclic Performance of Silicon-Aluminum Anodes for Lithium-Ion Cells
Si-Al composite anodes, where micron-sized Si particles were embedded in a ductile Al matrix, were electrochemically cycled in ethylene carbonate (EC)- and propylene carbonate (PC)-based electrolytes vs. Li/Li+. When cycled in PC-based electrolytes, cracks were not formed in Si at a low voltage scan rate of 0.50 mVs(-1). However, cracks formed in Si when lithiated in EC-based electrolytes and these cracks were arrested by the surrounding Al-matrix and subsequently closed during de-lithiation. Lithiation at a high scan rate of 5.00 mVs(-1) increased the crack formation probability but in PC-based electrolytes, only a few cracks were formed and then closed during de-lithiation. The results suggest that composite Si-Al anodes, which do not pulverize like monolithic Si, could provide durable electrodes for Li-ion batteries-especially if they contain small Si particles (<10 mu m) and cycled in a PC-based electrolyte. (C) 2017 The Electrochemical Society. All rights reserved.