A 3D-printed square-hole electrode for dendrite-free zinc-air batteries

Rechargeable zinc-air batteries are regarded as the most promising energy storage batteries due to their excellent theoretical energy density, safety and environmental friendliness. However, the uncontrolled growth of zinc dendrites seriously limits the cycling stability and performance of zinc-air batteries. By combining 3D printing with chemical etching and electro-deposition of zinc, 3D Fe//Ni-Zn-1.2 can be prepared which shows excellent reversibility for plating/peeling. The prepared 3D Fe//Ni-Zn-1.2 has a reasonable lattice structure with excellent hydrophilicity, and dendrite-free growth is achieved. As expected, 3D Fe//Ni-Zn-1.2 has a more stable coulombic efficiency and higher stability and cycles continuously for 1050 h at 10 mA cm-2. With the exactly same electrode geometric area, the tested impedance of the 3D Fe//Ni-Zn-1.2 electrode is 0.074 omega (0.091 omega for 2D), indicating that the 3D structure has a more conducive interface with the electrolyte for zinc deposition. Such a reasonable electrode structure provides a solution for the development of high performance energy storage systems. A corrosion-resistant electrode was prepared by a combination of 3D printing and etching. It can be stable in alkaline solution for a long time. So the electrode can achieve a cycle life of more than 1000 h.

Automated summary

Rechargeable zinc-air batteries are considered highly promising for energy storage due to their theoretical energy density, safety, and environmental friendliness. However, the uncontrolled growth of zinc dendrites hinders their stability and performance. This study presents a 3D printed electrode with chemical etching and electro-deposition of zinc, which exhibits excellent reversibility and dendrite-free growth. The 3D electrode shows improved stability and coulombic efficiency, cycling continuously for 1050 hours at 10 mA cm-2. The electrode's impedance is also lower compared to a 2D electrode, indicating better interface compatibility for zinc deposition. The corrosion-resistant electrode prepared through this method achieves a cycle life of over 1000 hours.