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.