Abstract
Developing high-performance, safer, and affordable flexible batteries is of urgent need to power the fast-growing flexible electronics market. In this respect, zinc-ion chemistry employing aqueous-based electrolytes represents a promising combination considering the safety, cost efficiency, and both high energy and high-power output. Herein, we represent a highperformance flexible in-plane aqueous zinc-ion miniaturized battery constructed with all electrodeposited electrodes, i.e., MnO2 cathode and zinc anode with polyimide-derived interdigital patterned laser-scribed carbon (LSC) as the current collector as well as the template for electrodeposition. The LSC possesses a cross-linked network of graphitic carbon sheet, which offers large surface area over low footprint and ensures active materials loading with a robust conductive network. The LSC with high zincophilic characteristic also offers dendrite-free zinc deposition with very low Zn2+ plating stripping overpotential. Benefitting from the Zn//MnO2-rich redox chemistry, the ability of the 3D LSC network to uniformly distribute reaction sites, and the architectural merits of in-plane interdigitated electrode configuration, we report very high capacity values of similar to 549 mAh/g (or similar to 523 mu Ah/cm2) and 148 mAh/g (or 140 mu Ah/cm2) at 0.1 A/g (0.095 mA/cm2) and 2 A/g (1.9 mA/cm2) currents, respectively. The device was also able to maintain a high capacity of 196 mAh/g (areal capacity of 76.19 mu Ah/cm2) at 1 A/g (0.95 mA/cm2) current after 1350 cycles. The flexibility of the device was demonstrated in polyacryl amide (PAM) gel polymer soaked with a 2 M ZnSO4 and 0.2 M MnSO4 electrolyte, which exhibited a comparable specific capacity of similar to 102-110 mAh/g in flat condition and different bending (100 degrees or 160 degrees bending) conditions. The device does not use any conventional current collector, separator, and conductive or polymer additives. The overall process is highly scalable and can be completed in less than a couple of hours.