ABSTRACT
The capacity, cycle-life and life time of Si Lithium-Ion batteries are closely dependent on the ability of its electrodes to avoid fracture failure brought by de/litigation during charging/discharging cycles. In this paper we study the effect of film thickness, on the formation of crack patterns systematically. Applying the Mixed-mode Cohesive Zone interface model on the film/substrate system, a developed finite element numerical model has been carried out under plane strain condition, the whole fracture process and crack pattern of silicon film with different thickness is documented. With the growth of the Si film thickness, the average crack spacing length is increase, which is in good qualitative agreement with former experimental results and other theoretical model. The results shown that two-dimensional film-substrate system model can capture the essential features of cracking patterns of electrode materials and effectively characterize the relationship between crack pattern of thin film Lithium-Ion Battery electrodes and the thickness of Si thin film.
