Recycling of Zinc-Carbon Batteries into MnO/ZnO/C to Fabricate Sustainable Cathodes for Rechargeable Zinc-Ion Batteries.

ABSTRACT

Acidic zinc-carbon dry batteries have been widely used in life because of their low cost. However, a great quantity of used batteries is discarded as refuse, which not only wastes resources but also leads to environmental contamination. To reuse spent batteries on a large scale, this study concerns a simple, effective, and sustainable strategy to turn them into MnO/ZnO/C composites. After a conventional leaching treatment followed by pyrolysis, the rust cathode materials can be reduced to MnO/ZnO/C. When serving as a rechargeable zinc-ion battery cathode, this electrode provides a maximum reversible capacity of around 362 mAh g-1 MnO ) and a rate capability of 191 mAh g-1 MnO at a high current rate of 1.20 A g-1 . Furthermore, ZnO gradually dissolves in the electrolyte with the increase of discharge cycles, replenishing the Zn2+ content in the electrolyte and further enhancing cycling stability (98.02 % after 500 cycles). The device also exhibits a remarkable energy density of 336.37 Wh kg-1 , low self-discharge rate, and can efficiently power a LED panel. This strategy offers an economical and facile route to convert zinc-carbon battery waste into useful materials for aqueous rechargeable zinc ion batteries.