ABSTRACT The demand for the large-scale storage system has gained much interest. Among all the criteria for the large-scale electrical energy storage systems (EESSs), low cost ($ k Wh−1) is the focus where MnO2-based electrochemistry can be a competitive candidate. It is notable that MnO2 is one of the few materials that can be employed in various fields of EESSs: alkaline battery, supercapacitor, aqueous rechargeable lithium-ion battery, and metal-air battery. Yet, the technology still has bottlenecks and is short of commercialisation. Discovering key parameters impacting the energy storage and developing systematic characterisation methods for the MnO2 systems can benefit a wide spectrum of energy requirements. In this review, history, mechanism, bottlenecks, and solutions for using MnO2 in the four EESSs are summarised and future directions involving more in-depth mechanism studies are suggested.

中文翻译：

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电能存储系统含水电解质中二氧化锰的机理研究综述

摘要 对大规模存储系统的需求引起了人们的极大兴趣。在大规模电能存储系统 (EESS) 的所有标准中，低成本 ($ k Wh-1) 是重点，基于 MnO2 的电化学可以成为有竞争力的候选者。值得注意的是，MnO2 是少数可用于 EESS 各个领域的材料之一：碱性电池、超级电容器、水性可充电锂离子电池和金属空气电池。然而，该技术仍然存在瓶颈，缺乏商业化。发现影响能量存储的关键参数并开发 MnO2 系统的系统表征方法可以使广泛的能源需求受益。在这次回顾中，历史、机制、瓶颈、