Proton enhanced dynamic battery chemistry for aprotic lithium–oxygen batteries

• Published in: Nature communications Vol. 8; no. 1; p. 14308
• Main Authors: Zhu, Yun Guang, Liu, Qi, Rong, Yangchun, Chen, Haomin, Yang, Jing, Jia, Chuankun, Yu, Li-Juan, Karton, Amir, Ren, Yang, Xu, Xiaoxiong, Adams, Stefan, Wang, Qing
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 06.02.2017; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 140/133; 639/4077/4079/891; 639/638/161/891; ENERGY STORAGE; Fourier transforms; Humanities and Social Sciences; Lithium; multidisciplinary; Oxidation; Protons; Science; Science (multidisciplinary); Singapore
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms14308

Water contamination is generally considered to be detrimental to the performance of aprotic lithium–air batteries, whereas this view is challenged by recent contrasting observations. This has provoked a range of discussions on the role of water and its impact on batteries. In this work, a distinct battery chemistry that prevails in water-contaminated aprotic lithium–oxygen batteries is revealed. Both lithium ions and protons are found to be involved in the oxygen reduction and evolution reactions, and lithium hydroperoxide and lithium hydroxide are identified as predominant discharge products. The crystallographic and spectroscopic characteristics of lithium hydroperoxide monohydrate are scrutinized both experimentally and theoretically. Intriguingly, the reaction of lithium hydroperoxide with triiodide exhibits a faster kinetics, which enables a considerably lower overpotential during the charging process. The battery chemistry unveiled in this mechanistic study could provide important insights into the understanding of nominally aprotic lithium–oxygen batteries and help to tackle the critical issues confronted. Water is believed to undermine the performance of aprotic lithium–air batteries. However, the authors here disclose different battery chemistry, showing that both lithium ions and protons are involved in the battery reactions in the presence of water, leading to an unprecedented dynamic product.