Towards a Porous Zinc Anode Design for Enhanced Durability in Alkaline Zinc–Air Batteries

The commercialization of rechargeable alkaline zinc–air batteries has been constrained by critical challenges associated with the zinc electrode, including passivation, dendrite growth, and hydrogen evolution reaction. These issues severely limit the cycle life and pose a major barrier to large-scale industrial deployment. Integration of porous anode structures and electrode additives—two widely investigated approaches for mitigating challenges related to zinc anode—shows significant promise. However, effectively combining these approaches remains challenging. This study introduces a method for fabricating zinc anodes that can combine the benefits of a porous structure and electrode additive. The polytetrafluoroethylene (PTFE) polymer binder used in fabricating the anode material resulted in a stable scaffold, providing the desired anode porosity of approximately 60% and effectively anchoring ZnO nanoparticles. The zinc anodes prepared using a nickel mesh current collector without any electrode additives demonstrated stable cycling performance, sustaining 350 cycles at a current density of 60 mA gZn−1 with a coulombic efficiency of approximately 95%. Incorporating 2 wt.% Bi2O3 as an electrode additive further enhanced the cycling performance, achieving 200 stable cycles with 100% coulombic efficiency under an increased current density of 120 mA gZn−1, signifying the effectiveness of the proposed fabrication strategy.