水系固态锌离子电池的制备与电化学性能研究Preparation and Electrochemical Performance of Water-Based Solid-State Zinc Ion Batteries

DOI: 10.12677/NAT.2019.93009, PDF, HTML, XML, 下载: 687  浏览: 2,744  科研立项经费支持

Abstract: The water-based solid state zinc ion battery (ZIB) has attracted much attention in the energy field of wearable electronic devices because of its safety, flexibility and low cost. The development of solid electrolytes with high zinc ion mobility is one of the hotspots for water-based solid state zinc ion batteries. In this paper, gelatin, potassium persulfate, acrylamide and N,N’-methylenebisacrylamide were used as raw materials, and the solid hydrogel electrolyte was prepared through grafting polyacrylamideonto gelatin via free radical polymerization method. The α-MnO2 fabricated by hydrothermal method was used as the positive electrode material, and the zinc synthesized by electrodeposition method was used as negative electrodematerial. As a result, a water-based solid zinc ion battery with a sandwich configuration was assembled. High ionic mobility of 0.37 mS•cm−1 was computed out from the electrochemical impedance spectroscopy. And at the current density of 3333 mA/g, the first specific discharge capacity reached 231.5 mAh/g, and the highest specific capacity at 307 mA/g current density reached 314 mAh/g.

1. 引言

2. 实验部分

2.1. 水系固态凝胶电解质的制备

Figure 1. Flow chart for the preparation of an aqueous solid electrolyte

Figure 2. (a) (b) Aqueous solid gel electrolyte; (c) Battery assembly schematic diagram

2.2. 正极材料的制备

2.3. 负极材料的制备

2.4. 锌离子电池的组装

3. 材料表征

Figure 3. XRD patterns of MnO2 synthesized by hydrothermal method at different reaction times (9 h, 12 h, 15 h, 18 h, 21 h, 24 h)

Figure 4. Scanning electron microscope (SEM) image of MnO2 at different magnifications

4. 电化学性能测试与分析

${\text{MnO}}_{\text{2}}+\frac{1}{2}\text{Zn}+\frac{1}{6}{\text{ZnSO}}_{\text{4}}+\frac{\text{x}}{6}{\text{H}}_{\text{2}}\text{O}\to \text{MnOOH}+\frac{\text{1}}{\text{6}}{\text{ZnSO}}_{\text{4}}{\left[\text{Zn}{\left(\text{OH}\right)}_{\text{2}}\right]}_{\text{3}}\cdot {\text{xH}}_{\text{2}}\text{O}$

Figure 5. (a) Cyclic voltammetry curves of zinc ion batteries at different scan rates; (b) Constant current charge and discharge curves of samples at different current densities; (c) Nyquist curves of sample AC impedance, the illustration is high frequency Area enlargement diagram and circuit simulation equivalent diagram

$C=I·t/m$ (1)

$\sigma =d\cdot {\left({R}_{ct}-{R}_{s}\right)}^{-1}·{A}^{-1}$ (2)

NOTES

*通讯作者。