Hu Yida, Liu Zhexuan, Li Lanyan, Guo Shan, Xie Xuefang, Luo Zhigao, Fang Guozhao, Liang Shuquan
School of Materials Science and Engineering, Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province, Central South University, Changsha 410083, China.
School of Science, Hunan University of Technology and Business, Changsha 410205, China.
Natl Sci Rev. 2023 Aug 16;10(10):nwad220. doi: 10.1093/nsr/nwad220. eCollection 2023 Oct.
Low-cost, high-safety, and broad-prospect aqueous zinc-manganese batteries (ZMBs) are limited by complex interfacial reactions. The solid-liquid interfacial state of the cathode dominates the Mn dissolution/deposition process of aqueous ZMBs, especially the important influence on the mass and charge transfer behavior of Zn and Mn. We proposed a quasi-eutectic electrolyte (QEE) that would stabilize the reversible behavior of interfacial deposition and favorable interfacial reaction kinetic of manganese-based cathodes in a long cycle process by optimizing mass and charge transfer. We emphasize that the initial interfacial reaction energy barrier is not the main factor affecting cycling performance, and the good reaction kinetics induced by interfacial deposition during the cycling process is more conducive to the stable cycling of the battery, which has been confirmed by theoretical analysis, quartz crystal microbalance with dissipation monitoring, depth etching X-ray photon-electron spectroscopy, etc. As a result, the QEE electrolyte maintained a stable specific capacity of 250 mAh g at 0.5 A g after 350 cycles in zinc-manganese batteries. The energy density retention rate of the ZMB with QEE increased by 174% compared to that of conventional aqueous electrolyte. Furthermore, the multi-stacked soft-pack battery with a cathodic mass load of 54.4 mg maintained a stable specific capacity of 200 mAh g for 100 cycles, demonstrating its commercial potential. This work proves the feasibility of adapting lean-water QEE to the stable aqueous ZMBs.
低成本、高安全性且前景广阔的水系锌锰电池（ZMBs）受到复杂界面反应的限制。阴极的固液界面状态主导着水系锌锰电池的锰溶解/沉积过程，尤其是对锌和锰的质量和电荷转移行为有重要影响。我们提出了一种准共晶电解质（QEE），通过优化质量和电荷转移，在长循环过程中稳定界面沉积的可逆行为以及锰基阴极良好的界面反应动力学。我们强调，初始界面反应能垒不是影响循环性能的主要因素，循环过程中界面沉积诱导的良好反应动力学更有利于电池的稳定循环，这已通过理论分析、带耗散监测的石英晶体微天平、深度蚀刻X射线光电子能谱等得到证实。结果，在锌锰电池中，QEE电解质在350次循环后，在0.5 A g的电流密度下保持了250 mAh g的稳定比容量。与传统水系电解质相比，采用QEE的ZMB的能量密度保持率提高了174%。此外，阴极质量负载为54.4 mg的多层软包电池在100次循环中保持了200 mAh g的稳定比容量，展现了其商业潜力。这项工作证明了将贫水QEE应用于稳定的水系ZMBs的可行性。
