Comprehensive Analyses of Aqueous Zn Metal Batteries: Characterization Methods, Simulations, and Theoretical Calculations

Aqueous zinc metal batteries (AZMBs) are regarded as competitive candidates for next-generation energy storage owing to their low cost, high performance, high safety, and high environmental friendliness. However, serious issues, including Zn dendrites, chemical corrosion, H-2 evolution, and sluggish Zn2+ diffusion kinetics, have largely impeded the commercial application of AZMBs. To understand these issues in depth and identify countermeasures, comprehensive analyses of AZMBs have continuously been developed. In this review, a detailed overview of the analytical techniques used to study AZMBs, including characterization methods, simulations, and theoretical calculations is presented, which provides a comprehensive toolbox for further research. Conventional characterization methods that provide preliminary information are first summarized. Various in situ techniques, including visualization and spectral characterization, are then discussed. These advanced real-time monitoring techniques contribute to a deeper understanding of the battery failure mechanism. Simulations and theoretical calculations are then presented in detail, enabling an in-depth investigation of the mechanism at the atomic level. Theoretical analyses can not only explore the mechanism in more detail, but also play a key role in guiding research and predicting future directions. Finally, the challenges and perspective of comprehensive analyses of AZMBs are discussed.