Continuum modeling of plasticity, diffusion and chemical reactions in Li-ion batteries
Laurence Brassart (University of Louvain), Kejie Zhao (MIT), Zhigang Suo (Harvard University)
Lithium ion batteries: When Chemistry meets Mechanics
Tue 2:40 - 4:00
Salomon 003
In the development of the next generation of batteries with high capacity, improving our understanding of the complex interplay between mechanics and chemistry in electrode materials appears as a crucial issue. The lithiation reactions in batteries lead to a variety of mechanical phenomena, such as large deformations, plasticity and fracture. Conversely, mechanics can influence the chemistry of lithiation in a significant manner. Stress affects the kinetics of surface and bulk reactions and the diffusion of lithium within the host. In this work we develop a continuum theory to investigate the strong coupling between mechanics and chemistry in electrode materials. The theory is written within a consistent thermodynamic framework and accounts for large strains. In particular, the model introduces a coupling between the kinetics of plastic flow and that of insertion reaction. The model formulation is supported by ab-initio calculations, as well as experimental measurements on thin film electrodes.