A Numerical Study of Mechanical Degradation of Carbon-Coated Graphite Active Particles in Li-ion Battery Anodes

Abstract

Current trends in portable electronic devices,1,2 electric vehicles,3–5 or renewable energy systems6–8 demand the development of lithium-ion batteries (LIBs) with improved capacity and performance.9–12 One critical component in LIBs is the negative electrode (i.e., anode),13 whose behavior has an important impact on the cell’s performance since it hosts the active materials in which Li intercalation and deintercalation occurs. During operation, both chemical and mechanical degradation occurs inside LIBs, resulting in a decreased battery performance and shortened battery life.14 The former is caused by the side reactions within the LIB that consume the number of lithium ions available for successive battery cycles and, therefore, cause battery capacity loss. The latter is due to the mechanical stresses originated within the electrode materials that may lead to fracture.15–17 Cracks in the active material that composes the electrode can isolate parts where intercalation will not occur.