A Phase-Field Model of Dendrite Growth of Electrodeposited Zinc

Zinc possesses good electrochemical reversibility, high energy density, easy availability and low cost, which is widely used in secondary batteries. However, the problem of dendrite growth remains unresolved in the process of zinc regeneration, severely influencing cycle life of zinc base batteries. It is of great importance for inhibition of dendritic morphology to explore the mechanism of dendrite growth at the electrode surface. Here we present a phase-field model of shape change of electrodeposited zinc, simulating morphological behavior of the liquid-solid interface and investigating effects of activation overpotential, ion concentration, electrolyte conductivity and ion diffusivity and anisotropy of interfacial energy on dendrite growth of electrodeposited zinc. The results demonstrate that dendrite growth is mainly related to uneven distribution of ions from electrochemical reaction, and the dendritic morphology can be effectively controlled by means of increase of zinc oxide concentration, electrolyte conductivity and ion diffusivity. These findings can be applicable to metal electrodeposition and zinc base batteries.