Long lifespan and high-rate Zn anode boosted by 3D porous structure and conducting network

Aqueous rechargeable Zn batteries are attractive for emerging generations of large-scale energy storage due to their high safety, low cost, and high energy density . It is regrettable that the poor cycling performance limits its further commercialization due to the troublesome dendrite growth and short-circuiting issue of the traditional planar Zn anode. Herein, in this work, a three-dimensional porous Zn anode (3D ZnP/CF) composed of highly conductive carbon fiber-based network and active zinc powder fillers is designed for long lifespan aqueous Zn batteries . The new 3D ZnP/CF exhibits controlled deposition behavior and scarce short-circuiting benefiting from the fast ionic/electronic transfer and sufficient deposition space, which are enabled by the porous structure and conducting network of the anode. The symmetric cell based on 3D ZnP/CF exhibits small voltage hysteresis of 25.1 mV and extraordinarily long cycling stability of 3000 h, particularly excellent high-rate performance (8 mA cm −2 , 8 mA h cm −2 , 700 h), which is superior to those of the reported static Zn metal batteries. Furthermore, the assembled full cell with manganese oxide as cathode exhibits superb capacity retention of 93.2% over 7000 cycles. The structural and compositional design provides another effective approach for the commercialization of aqueous rechargeable Zn batteries.