同溶剂电解质设计以抑制相位过渡到高性能K+/Zn2+混合电池
Wei Chen1, Jiahao Wu1, Kai Fu1
1State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Materials Science and Engineering, Wuhan University of Technology, Wuhan, Hubei, 430070, P. R. China.
Small methods
|July 9, 2023
概括
研究人员开发了一种新的水性混合离子电池,使用六酸 (MnHCF) 和一种独特的电解质. 这种设计提高了稳定性和性能,克服了基电池的关键挑战.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 六酸 (MnHCF) 是水性电池的有希望的阴极材料,因为它的安全性,能量密度和成本.
- 水性电池的挑战包括MnHCF相位过渡和由离子 (Zn2+) 特性引起的性能差.
研究的目的:
- 为了克服MnHCF在水性电池中的局限性.
- 为了提高基于MnHCF的阴极的稳定性和性能.
- 开发高能量密度的水性混合离子电池.
主要方法:
- 使用碳酸 (PC),三甲硫酸 (OTf) 和水设计和建造了一个特定的溶解结构.
- 准备了一种K+/Zn2+混合电池,采用MnHCF阴极,金属阳极,以及一种KOTf/Zn(OTf) 2电解质与PC同溶剂.
主要成果:
- 添加PC成功抑制了从MnHCF到六酸盐 (ZnHCF) 的相位过渡.
- 电解质修饰扩大了电化学稳定性窗口,并抑制了树突的生长.
- 该MnHCF/Zn混合电池实现了118 mAh g-1的可逆容量,在1000个循环后保持65.6%的1A g-1.
结论:
- 电解质溶解结构的合理设计对于推进水性混合离子电池至关重要.
- 开发的基于PC的电解质显著提高了MnHCF阴极的循环稳定性和速率性能.
- 这项工作为高能量密度和稳定的水性混合离子电池技术铺平了道路.
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