A concentrated electrolyte for zinc hexacyanoferrate electrodes in aqueous rechargeable zinc-ion batteries

2017 2nd International Conference on Innovative Engineering Materials

Kim, D.^1 ; Lee, C.^1 ; Jeong, S.^1

Department of Chemical Engineering, Soonchunhyang University, Chungnam, Asan

336-745, Korea, Republic of^1

关键词: Charge/discharge capacities;    Cycling performance;    Electrochemical performance;    Electrochemical test;    Hydration number;    Structured materials;    Synthesized materials;    Zinc hexacyanoferrate;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/284/1/012001/pdf
DOI  :  10.1088/1757-899X/284/1/012001

来源: IOP

【 摘 要 】

In this study, a concentrated electrolyte was applied in an aqueous rechargeable zinc-ion battery system with a zinc hexacyanoferrate (ZnHCF) electrode to improve the electrochemical performance by changing the hydration number of the zinc ions. To optimize the active material, ZnHCF was synthesized using aqueous solutions of zinc nitrate with three different concentrations. The synthesized materials exhibited some differences in structure, crystallinity, and particle size, as observed by X-ray diffraction and scanning electron microscopy. Subsequently, these well-structured materials were applied in electrochemical tests. A more than two-fold improvement in the charge/discharge capacities was observed when the concentrated electrolyte was used instead of the dilute electrolyte. Additionally, the cycling performance observed in the concentrated electrolyte was superior to that in the dilute electrolyte. This improvement in the electrochemical performance may result from a decrease in the hydration number of the zinc ions in the concentrated electrolyte.