Qiu Xuan, Wang Nan, Dong Xiaoli, Xu Jie, Zhou Kang, Li Wei, Wang Yonggang
Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Fudan University, Shanghai, 200433, China.
Angew Chem Int Ed Engl. 2021 Sep 13;60(38):21025-21032. doi: 10.1002/anie.202108624. Epub 2021 Aug 11.
Owing to undesired Zn corrosion and the formation of Zn dendrites in aqueous electrolytes, most of the examples of aqueous Zn batteries with reported excellent performance are achieved with low Zn-utilization (<0.6 %) in the anode and low mass-loading (<3 mg cm ) in the cathode. Herein, we propose a new organic electrolyte for Zn batteries, which contains a zinc trifluoromethanesulfonate (Zn-TFMS) salt and a mixed solvent consisting of propylene carbonate (PC) and triethyl phosphate (TEP). We demonstrate that this electrolyte with an optimized PC/TEP ratio not only exhibits high ionic conductivity and a wide stable potential window, but also facilitates dendrite-free Zn plating/stripping. In particular, the TEP solvent makes the electrolyte nonflammable. Finally, a 2 V Zn//polytriphenylamine composite (PTPAn) battery is fabricated with the optimized electrolyte; it shows a high rate and a long lifetime (2400 cycles) even with a high mass-loading (16 mg cm ) of PTPAn in the cathode and with a high Zn-utilization (3.5 %).
由于水性电解质中存在不希望发生的锌腐蚀以及锌枝晶的形成，大多数已报道具有优异性能的水性锌电池实例都是在阳极低锌利用率（<0.6%）和阴极低质量负载（<3 mg cm²）的情况下实现的。在此，我们提出了一种用于锌电池的新型有机电解质，它包含三氟甲磺酸锌（Zn-TFMS）盐以及由碳酸丙烯酯（PC）和磷酸三乙酯（TEP）组成的混合溶剂。我们证明，这种具有优化PC/TEP比例的电解质不仅具有高离子电导率和宽稳定电位窗口，而且有利于无枝晶的锌电镀/剥离。特别地，TEP溶剂使电解质不可燃。最后，用优化后的电解质制备了一个2 V的锌//聚三苯胺复合材料（PTPAn）电池；即使在阴极PTPAn的高质量负载（16 mg cm²）和高锌利用率（3.5%）的情况下，它仍显示出高倍率性能和长寿命（2400次循环）。
