Promoting Reversible Dissolution/Deposition of MnO<sub>2</sub> for High‐Energy‐Density Zinc Batteries via Enhancing Cut‐Off Voltage
Pengchao Ruan, Xilian Xu, Dong Zheng, Xianhong Chen, Xinyu Yin, Shuquan Liang, Xianwen Wu, Wenhui Shi, Xiehong Cao, Jiang Zhou
Abstract
Abstract Zn//MnO 2 batteries based on the MnO 2 /Mn 2+ conversion reaction mechanism featuring high energy density, safety, and affordable cost are promising in large‐scale energy storage application. Nonetheless, the continuous H + intercalation at low potential reduces the average output voltage and the energy efficiency, impeding the development of the high‐performance zinc battery. In this work, a strategy was proposed of enhancing the cut‐off voltage from the perspective of electrochemical parameters, toward high energy efficiency and stable output voltage of the Zn//MnO 2 battery. This strategy was beneficial to promoting MnO 2 dissolution/deposition through the increase of acidity caused by the constant accumulation of MnO 2 and inhibiting H + (de)intercalation during cycling process, thereby improving the energy efficiency (83.5 %) along with the stable average output voltage (1.88 V) under the cut‐off voltage of 1.8 V. This work provides a new pathway to promote aqueous zinc batteries with high energy density and stable output voltage.