Regulating the Thermodynamic Uniformity and Kinetic Diffusion of Zinc Anodes for Deep Cycling of Ah-Level Aqueous Zinc-Metal Batteries

Zn metal anodes in mildly acidic electrolytes usually suffer from a series of problems, including parasitic dendrite growth and severe side reactions, significantly limiting the Zn utilization efficiency and cycling life. A deep understanding of the Zn stripping/plating process is essential to obtain high-efficiency and long-life Zn metal anodes. Here, the factors affecting the Zn stripping/plating process are revealed, suggesting that thermodynamic uniformity in bulk structures promotes an orderly Zn stripping process, and a fast kinetic diffusion rate on the Zn surface facilitates uniform Zn deposition. Then, a bulk and surface co-optimized strategy for stabilizing Zn metal anodes is proposed, which is confirmed to effectively suppress the Zn dendrite growth and side reactions. Thus, the modified Zn anodes display record-breaking cycling lives of 1200 and 200 h under ultrahigh Zn utilization efficiencies of 80 and 93.5%, respectively. More importantly, using this modified Zn metal anode enables us to realize Ah-level pouch cells for continuous cycles under harsh conditions.