An integrated configuration with robust interfacial contact for durable and flexible zinc ion batteries

The flexible zinc ion battery (ZIB) is deemed to be a promising candidate for flexible power supply due to its high security and low cost. However, conventional segregated battery configuration inevitably suffers from the relative displacement or detachment between two neighboring components at bending strain, which seriously degrade the performance of a flexible battery. Moreover, stubborn Zn dendrite drastically shortens the cycle life. Herein, by integrating Zn anode, zinc protective coating, polyamide separator and cathode into a single matrix, referred as the integrated electrode, a long cycle life and robust flexibility for ZIB in aqueous electrolyte are achieved. Seamless connection with the adjacent layers not only avoids the relative displacement or detachment caused by bending strain, but enhances the interfacial contact to promote the electrochemical kinetics. The built-in protective coating in the integrated configuration significantly inhibits the dendrites and side reactions for extending the durability. Furthermore, the integrated configuration makes the whole battery lighter, thinner and more powerful. Therefore, this work provides a new design idea for engineering innovative battery configuration and enables high performances for a flexible ZIB. Meanwhile, the research results would deliver great potential applications in flexible electronics and boost the development of configuration of energy storage devices.