3D Printed Flexible Zinc Ion Micro-Batteries with High Areal Capacity Toward Practical Application

Printed zinc ion micro-batteries (PZIMBs) possess characteristics such as miniaturization, customizability, and affordability, making them highly promising for the field of flexible electronic devices. Nevertheless, the current development of PZIMBs is seriously hindered by their limited areal capacity. In this study, PZIMBs with a high areal capacity are conducted based on 3D printing technology by optimizing the material properties, electrode ink formulation, and printing parameters. The cathode material, polyvinylpyrrolidone-induced ammonium vanadate (P-NVO) nanobelt, exhibits a high capacity of 457.3 mAh g −1 at 0.1 mA g −1 , along with good cycling performance and rate capability. The double-network hydrogel electrolyte, composed of crosslinked polyacrylamide-polyvinylpyrrolidone (PAM-PVP hydrogel electrolyte), demonstrates excellent ionic conductivity (107.22 mS cm −1 ), high stretchability (970%), and viscosity. The constructed PZIMBs exhibit a high areal capacity of 4.02 mAh cm −2 at 0.5 mA cm −2 , along with good mechanical flexibility. Moreover, through the integration of PZIMBs with pressure sensors, an interactive system is developed that resembles electronic skin, and this integration enables practical applications of wearable devices. This study presents a novel approach for fabricating PZIMBs with high areal capacity, thereby contributing to and propelling the advancement of flexible energy storage.