Dual-protection strategy for superior stability and performance of zinc powder-based anodes in aqueous zinc-ion batteries†
Abstract
Aqueous zinc-ion batteries (AZIBs) are an attractive alternative to lithium-ion batteries due to their safety, cost-effectiveness, and environmental friendliness. However, the commercialization of AZIBs is hindered by issues such as dendrite formation, side reactions, and poor utilization of zinc anodes. To address these challenges, we developed a dual-protection strategy incorporating reduced graphene oxide (rGO)-encapsulated zinc powder and a polyacrylic acid (PAA) binder. The rGO layer acts as a physical barrier, suppressing dendrite growth and minimizing side reactions, while the PAA binder enhances electrolyte affinity and ensures uniform zinc-ion deposition through hydrogen bonding. This synergistic system demonstrated exceptional electrochemical performance, achieving stable cycling with a significantly reduced overpotential. Symmetric cells exhibited prolonged cycle life exceeding 670 h at a high depth of discharge (33%) with minimal degradation. Additionally, full cells paired with ammonium vanadate nanofiber cathodes achieved high capacities and excellent retention, outperforming conventional zinc-powder-based anode configurations. This work provides a scalable and practical approach to improving the stability and performance of zinc powder-based anodes, offering a viable pathway toward next-generation energy storage systems.