Improving Electrochemical Performance in Planar On‐Chip Zn‐ion Micro‐Batteries via Interlayer Strategies

Abstract The imperative development of planar on‐chip micro‐batteries featuring high‐capacity electrodes and environmentally safer, cost‐effective, and stable systems is crucial for powering forthcoming miniaturized systems‐on‐chip smart devices. However, research in the area of high‐stability micro‐batteries is limited due to the complex fabrication process, the stability of micro‐electrodes during cycling, and the challenge of maintaining higher capacity within a limited device footprint. In response to this need, this study focuses on providing highly stable and high‐capacity micro‐electrodes. This involves adding a PEDOT layer between the electrode material and the current collector, applied within a planar polyaniline cathode and zinc anode device structure to enhance charge storage performance. This straightforward strategy not only improves device stability over long‐term cycling and reduces charge transfer resistance but also increases charge storage capacities from 17.64 to 19.75 µAh cm⁻² at 0.1 mA cm⁻². Consequently, the Zn‐ion micro‐batteries achieve notable peak areal energy and power of 18.82 µWh cm⁻² and 4.37 mW cm⁻², respectively. This work proposes an effective strategy to enhance the electrochemical performance of planar micro‐batteries, a critical advancement for the development of advanced portable electronics.