Experimental measurement of stress evolution in silicon carbide composite electrode during electrochemical cycling

• DOI: 10.1016/j.mssp.2021.106275
• Publication Date: 2021-10-25T17:42:41Z
• Authors: Huijie Yu; Xingyu Liu; Dawei Li
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract Silicon carbide composite electrodes offer great potential for LIBs because of its relatively high energy density and low expansion rate. In this work, the bending deformation and mechanical properties of the silicon carbide composite electrode were measured by an in-situ curvature measurement system (CMS). The results show that the curvature of the bilayer electrode increase during the lithiation process, and decreases during the delithiation process. Meanwhile, a theoretical model is employed to analyze mechanical deformation and properties, such as curvature, Young's modulus, strain, and stress. The Young's modulus of the composite electrode increases from 0.14 GPa to 0.38 GPa corresponding to a normalized capacity of 40%. And, the stress of the composite electrode increases from 0 MPa to the maximum value of 14.8 MPa during the lithiation process and then decreases to 2.5 MPa during the delithiation process. Obviously, the stress in composite silicon carbide electrode is relatively smaller than that of the pure silicon electrode.