Sundararajan Natarajan

Abstract:

Modelling fracture in batteries has attracted the research community as it accounts for more than 80% capacity loss within the first few cycles of charging/discharging. Cracking leads to loss of contact between particles and no longer participates in the insertion/extraction process and becomes inactive, leading to decreased capacity. Further, there are also local changes in the material properties, which has influence on the macroscopic response of the battery. In this work, we present a novel adaptive phase field formulation to simulate fracture in Li-ion batteries. Within this, a multi-physics framework is adopted where in the influence of the stress induced diffusion and diffusion induced stress on the fracture is numerically studied. A promising aspect of this framework is that complex fracture networks can easily be handled thanks to phase field method and the computational overhead is addressed by a novel adaptive technique based on physics based refinement. The influence of various boundary conditions, size of the particles on the fracture process are systematically studied. The results from the present framework are compared with experimental results where available.