Reaction mechanism and electrochemical performance of manganese (II) oxide in zinc ion batteries

Abstract

Due to the abundant manganese reserves and the ability to provide higher voltages, the Mn3+ and Mn4+ cathode materials have been widely studied in zinc-ion batteries (ZIBs). However, there are some common disadvantages including poor conductivity and the expansion in volume during cycling, which exist in these Mn3+ and Mn4+ materials. Herein, we applied pure MnO as an electrode material to ZIBs and discussed the reaction mechanism. Specifically, the energy density could reach 431.5 mAh g−1 at 0.2 A g−1, which was the highest in the Mn-based materials. It also showed high capacity (187.8 mAh g−1) after 500 cycles at 1A g−1. And after 1200 cycles at 1.5 A g−1, the capacity retention rate was still at 87.3%, suggesting the great long-life cycling. This kind of MnO encapsulated by carbon can bring new opportunities for Mn-based ZIBs.