Vertical Graphene Film Enables High-Performance Quasi-Solid-State Planar Zinc-Ion Microbatteries

Abstract

With the advantages of low cost, high safety, and environmental friendliness, quasi-solid-state zinc-ion microbatteries (ZIMBs) have received widespread attention in the field of flexible wearable devices and on-chip integratable energy storage. However, hysteresis Zn-ion transport kinetics and inhomogeneous growth of the zinc anode result in the poor capacity reversibility and cycling stability. Herein, a quasi-solid-state planar zinc-ion cell was developed by employing a vertical graphene (VG) film as an effective conductive modification layer for both the cathode and anode. The VG distinctly induces uniform Zn deposition/stripping, accelerates the charge transport, and enhances the adhesion between the active materials and current collectors. As a result, planar Zn@VG//MnO 2 @VG exhibits a high areal capacity of 159 μAh cm −2 , a remarkably high areal energy/power density of 201.5 μWh cm −2 /67.16 μW cm −2 , and a high capacity retention of 95.6% at a bending angle of 180°. The proposed facile strategy for electrode modification provides a new insight into the design of high-performance flexible and planar ZIMBs.

Laser-assisted fabrication of a 3D cross-linked V2CTx/rGO microelectrode for high-rate aqueous zinc-ion microbatteries

“…As shown in Table S1, † the energy and power densities of the AZIMB in this work can reach 353.54 mW h cm −2 and 615.8 mW cm −2 , which is much larger than those of other microbatteries. 8,[39][40][41][42][43][44][45] The XPS analysis method was employed to elucidate the mechanism of the insertion/extraction reaction of Zn 2+ ions on the 3D VO x -V 2 CT x @rGO-50% microelectrode in fully discharged and charged states, by analyzing the valence state waveform of major elements. In Fig.…”

“…As shown in Table S1,† the energy and power densities of the AZIMB in this work can reach 353.54 μW h cm −2 and 615.8 μW cm −2 , which is much larger than those of other microbatteries. 8,39–45…”

A review of the preparation process and anode stabilization strategies of Zn microbatteries

“…When implementing coating technology, a comprehensive assessment of its influence on anode stability and plating/stripping kinetics is necessary to ensure the rationality and efficacy of the coating. For instance, Zhu et al successfully addressed the corrosion issue of ZMBs by employing polyimide coatings [126] , resulting in a significant reduction in the capacity loss of ZIBs in aqueous electrolytes. The numerous carbonyl oxygen atoms in the polyimide coating can coordinate with Zn 2+ in the electrolyte, forming a stable Zn layer.…”

Zinc micro-energy storage devices powering microsystems

“…This structure features multi-level microcracks at the macro scale and a nanoflower morphology at the microscale, enhancing electrolyte permeation and providing abundant active sites. Additionally, vertically aligned graphene films produced via CVD exhibit a large specific surface area [92], strengthening the adhesion between the cathodic active material and the current collector, and facilitating uniform zinc deposition/stripping on the anode. In sandwichtype ZMBs, deposition techniques are extensively utilized.…”