Dynamic behaviour of core-shell structured Si nanoparticles during lithiation/delithiation cycling at dynamic loadings

¹ Department of Automotive Engineering, School of Transportation Science and Engineering, Beihang University, Beijing, China
² Advanced Vehicle Research Center, Beihang University, Beijing, China
³ Department of Mechanical Engineering and Engineering Science, The University of North Carolina at Charlotte, Charlotte, NC 28223, United States
⁴ Vehicle and Battery Safety Laboratory, The University of North Carolina at Charlotte, Charlotte, NC 28223, United States

^* Corresponding author : jun.xu@uncc.edu

Published online: 7 September 2018

Abstract

Dynamic behaviours of the core-shell structured (CSS) Si nanoparticles during electrochemical cycling were modelled. A core-shell-structured model that contained Si nanoparticles wrapped with amorphous carbon (a-C) was established. The system was charged and discharged under constant voltage with a dynamic loading applied on the surface of the particle. The volume change and associated stress simulated by the model without external loading were compared with the previous work done by other researchers and matched well. Different imposing moments of the external loading were introduced into this model to see the dynamic effects on the cycling behaviour of the Si particles. The present study illustrate the dynamic behaviour under external loading, which would give guidance for the Si based battery design and help to understand the coupling effects of dynamic loading and electrochemical cycling on Si anodes.