Multichannel Pathways for Electron Transport in Batteries Using Carbon Composite Conductive Materials

Abstract

Rechargeable zinc-ion batteries (ZIBs) are gaining substantial attention as promising candidates for large-scale energy storage applications owing to their inherent safety, low cost, and eco-friendliness. However, despite numerous research efforts facilitating the advancement of this technology, the low electrical conductivity and inadequate utilization of the electrochemically active areas of manganese dioxide (MnO2), which is commonly used as a cathode material, have significantly limited the performance of these batteries. In this study, we formed high-conductivity network channels using carbon nanotubes (CNTs) as a conductive additive and provided oxygen functional groups on the surface of the cathode through surface activation using plasma treatment. Consequently, the CNT-incorporated and plasma-treated MnO2 (PCB@CNT-MnO2) cathode exhibited increased capacity (280.8 mAh g(-1) at 0.3 A g(-1)) and rate capability (131.2 mAh g(-1) at 2.0 A g(-1)). Furthermore, it demonstrated high stability with a specific capacity of 141.0 mAh g(-1) after 300 cycles at 0.5 A g(-1), proving the enhanced electrochemical performance of ZIBs. This approach presents a new practical strategy to achieve a high energy density in ZIBs using MnO2 cathodes.