Effective inhibition of Zn dendrites in Zn–air batteries through electrolyte engineering

Abstract

Rechargeable alkaline zinc–air batteries (ZABs) are promising candidates for energy storage and conversion. However, the uncontrolled growth of zinc dendrites in alkaline environments seriously affects their cycling stability and overall performance. Inspired by the advancements in aqueous zinc-ion batteries, electrolyte engineering is conducted using zinc citrate as an electrolyte additive to achieve a highly reversible zinc anode. The specific adsorption of zinc citrate induces a shielding effect that modulates Zn deposition behavior and preferentially activates the Zn (002) crystal plane, effectively suppressing dendrite formation. Notably, zinc citrate demonstrates robust performance across various electrochemical configurations, including Zn‖Cu asymmetric cells, Zn‖Zn symmetric cells, and full-cell tests. Remarkably, the full-cell test exhibits an extended cycle life of up to 2600 cycles (439 h) with a high gram-specific capacity of 825.5 mA h per g Zn at 20 mA cm⁻². These findings highlight the potential of electrolyte engineering as a viable strategy to mitigate dendrite growth in rechargeable ZABs, offering a pathway toward more efficient and durable zinc–air battery systems.