Engineering Aqueous Zn-MnO2 Microbatteries Using a Synergistic Reaction Mechanism

Aqueous Zn-MnO2 microbatteries (MBs) havereceived significantresearch attention due to their safety, thinness, flexibility, andhigh energy density. However, poor cycling stability, controversialreaction mechanisms, and complex fabrication processes have limitedtheir development and application. In this study, aqueous Zn-MnO2 MBs with a high volumetric energy density (1037.5 mWh cm(-3)), areal specific capacity (1777.5 mu Ah cm(-2)), and excellent cycling stability were successfullymanufactured. This was achieved by adding Mn2+ to the electrolyteand combining it with a low-cost, short-process, and customizablepatterned laser direct writing technique. The excellent propertiesstem from the following synergistic reaction mechanisms. (i) The additionof Mn2+ to the electrolyte inhibits the dissolution ofthe cathode material, and (ii) based on the traditional Mn3+/MnO2 redox conversion, the added Mn2+ canpromote the electrodeposition reaction conversion process of Mn2+/MnO2, thus supplementing the cathode materialand improving the capacity and cycling stability. In addition, wesuccessfully manufactured zinc-ion hybrid microsupercapacitors andactivated carbon-based microsupercapacitors with excellent performance,demonstrating the scalability of laser direct writing technology.This work proposes a synergistic reaction mechanism for aqueous Zn-MnO2 batteries; it provides a perspective for constructing MBswith excellent electrochemical properties.

Automated summary

This study successfully manufactured aqueous Zn-MnO2 microbatteries with high volumetric energy density, areal specific capacity, and excellent cycling stability by adding Mn2+ to the electrolyte and using a laser direct writing technique. The addition of Mn2+ inhibits the dissolution of the cathode material and promotes the electrodeposition reaction conversion process, improving the capacity and cycling stability of the batteries.