无机添加剂策略对回氧流电池电解质中的稳定性的影响 通过分子动力学
Anqi Guo1, Pengtu Zhang2, Shiling Yuan1,2
1Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100, China.
The journal of physical chemistry. B
|October 15, 2024
概括
像这样的无机离子添加剂通过防止氧化集群的形成,有效地稳定了氧化回氧流电池电解质. 氨离子作为优越的保护外,提高电池性能.
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
- 计算化学计算化学
背景情况:
- 全氧化还原流电池 (VRFB) 对大规模的能源存储具有前景.
- 温度稳定是影响VRFB性能和寿命的关键挑战.
- 氧化 (V2O5) 沉和VO2+聚合对电解质性能产生负面影响.
研究的目的:
- 研究无机离子添加剂 (Na+,K+,NH4+) 对VRFB电解质中VO2+的溶解结构和动态的影响.
- 了解这些添加剂如何影响V2O5降水和VO2+集群形成.
- 确定最佳的添加剂,以提高电解质稳定性和电池性能.
主要方法:
- 用分子动力学 (MD) 模拟来建模VRFB阳性电解质.
- 模拟的重点是溶解环境和VO2+离子的动态行为.
- 分析了Na+,K+和NH4+兴奋剂对V2O5沉和集群聚合的影响.
主要成果:
- VO2+离子倾向于聚集成类似链状的,而硫酸盐离子 (SO42-) 则会加剧这种情况.
- 杂的无机离子 (Na+,K+,NH4+) 在VO2+周围形成稳定的溶解层,作为抑制集群生长的保护.
- 与Na+和K+相比,离子 (NH4+) 显示出更高的分散能力,这是由于它们稳定地融入VO2+的第一个和第二个溶解.
结论:
- 无机离子可以有效地提高VRFB电解质的温度稳定性.
- 已确定NH4+是分散VO2+并防止有害集群形成的高效添加剂.
- 这项研究为修改VRFB阴极电解质以提高性能和寿命提供了宝贵的理论见解.
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