How simulations help better understand mechanism and design materials? Learning from aqueous zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) have attracted widespread attention for large-scale energy storage. However, most of the practical phenomena assocaited with AZIBs can only be explained by using infinitely modified model theories; thus, the underlying mechanisms of reactions in the AZIBs remains challenging to characterize. The dynamic evolution in AZIBs' response to applied bias potentials makes it difficult to accurately observe the behavior with current techniques in a non-vacuum environment. In response, theoretical simulations have been widely conducted to investigate the mechanisms of reactions occurring in the AZIBs. These theoretical simulations can considerably improve the understanding of the fundamental mechanisms, and further guide the AZIBs development. Density functional theory (DFT) calculations, molecular dynamics (MD) simulations and COMSOL simulations are three common approaches in the literature, which correspond to atomic-scale, molecular-scale and mesoscale analyses, respectively. Here, we summarize the key insights gained from these simulations to date and present our perspective on future research directions within this field.