清华大学康飞宇研究团队开发出一种自相分离的锌金属电池电解质。相关研究成果发表在2025年1月8日出版的《美国化学会杂志》。

水性锌（Zn）金属电池（ZMBs）因其安全性和环保性而受到广泛关注。尽管水性电解质有助于金属氧化物阴极的快速动力学，但它们与锌金属阳极的不相容性，会引发严重的析氢反应（HER）和枝晶生长。

该文提出了一种自相分离电解质（SPSE），以满足ZMBs中阳极和阴极的矛盾要求。分子建模和实验研究证实，具有中等介电常数和相对于水的较大Hildebrand参数差异的疏水性氟化溶剂，有助于SPSE在搅拌和老化过程中自发进行水相-非水相分离。在开发的SPSE中，阳极非水相通过调节锌沉积和保护性固体电解质界面（SEI）的协同作用，有效地抑制了HER和枝晶的形成。

同时，阴极中的水相确保了快速的离子插入/提取动力学。因此，SPSE使锌对称电池具有2500小时的循环寿命和超低腐蚀电流（0.08 mA cm^-2）。值得注意的是，Zn|SPSE|V₂O₅全电池可维持3000多次循环，HER和腐蚀可忽略不计，袋式电池在反复翻转时表现出卓越的运行稳定性。

该电解质设计理念为结合长期循环性、增强安全性和耐用性的实用ZMBs铺平了一条有前景的道路。

附：英文原文

Title: A Self-Phase Separated Electrolyte toward Durable and Rollover-Stable Zinc Metal Batteries

Author: Xin Zhao, Jiaping Fu, Ming Chen, Yao Wang, Cong Huang, Kun Qian, Guang Feng, Baohua Li, Dong Zhou, Feiyu Kang

Issue&Volume: January 8, 2025

Abstract: Aqueous zinc (Zn) metal batteries (ZMBs) have received great attention due to their safety and environmental friendliness. Although aqueous electrolytes facilitate fast kinetics in metal oxide cathodes, their incompatibility with the Zn metal anodes triggers severe hydrogen evolution reaction (HER) and dendrite growth. Herein, a self-phase separated electrolyte (SPSE) is proposed to fulfill the contradictory requirements of the anode and cathode in ZMBs. Molecular modeling and experimental investigations verify that the hydrophobic fluorinated solvent with moderate dielectric constant and large Hildebrand parameter disparity relative to water contributes to a spontaneous aqueous–nonaqueous phase separation within the SPSE against stirring and aging. In the as-developed SPSE, the anode nonaqueous phase effectively inhibits the HER and dendrite formation by a synergistic effect of regulated Zn deposition and protective solid electrolyte interphase (SEI). Meanwhile, the aqueous phase in the cathode ensures fast ion insertion/extraction dynamics. Consequently, the SPSE allows for Zn||Zn symmetrical cells with 2500 h cycle life and ultralow corrosion current (0.08 mA cm–2). Notably, the Zn|SPSE|V2O5 full cell sustains over 3000 cycles with negligible HER and corrosion, and the pouch cell demonstrates remarkable operation stability against repeated rollover. Our electrolyte design concept paves a promising path for practical ZMBs that combine long-term cyclability, enhanced safety, and durability.

DOI: 10.1021/jacs.4c15132

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c15132