提替代促进P2型Na2/3Mn2/3Ni1/3O2Na离子电池阴极中的阳离子还氧和循环稳定性
Neha Dagar1, Samriddhi Saxena1, Hari Narayanan Vasavan1
1Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Indore, Simrol, 453552, India.
概括
在P2型层氧化物中使用兴奋剂可以通过改善离子扩散和稳定性来提高离子电池的性能. 这项研究强调了Ti-doped Na2/3Mn2/3Ni1/3O2作为一个有前途的阴极材料.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 由于易于合成和离子扩散,P2型层氧化物是离子电池的主要阴极候选者.
- 优化阴极材料对于推进用于电网规模储能的离子电池技术至关重要.
研究的目的:
- 在各种电压范围内研究10%的Ti-doped P2型Na2/3Mn2/3Ni1/3O2的电化学行为.
- 了解Ti4+兴奋剂对离子/空隙排序,层间距和电化学性能的影响.
主要方法:
- 在不同的电压窗口 (1.5-4.0 V,2.0-4.0 V,2.0-4.5 V) 中进行电化学评估.
- 静电间歇定位技术 (GITT) 用于评估离子扩散.
- 电化学阻抗光谱 (EIS) 用于分析接口和电荷转移电阻.
主要成果:
- Ti4+ 兴奋剂破坏了 Na-ion/空位的排序,并增加了层间距,提高了速率性能 (在 2.0-4.0 V 的 5C 时 ~68 mAh g-1).
- 在2.0-4.5V范围内,Ti-doped材料由于增强的阳离子氧化还原可逆性,显示出更好的容量保留 (71%在100个循环后).
- NMNT表现出卓越的循环稳定性 (在1.5-4.0V的0.33C下保持80%),更高的Na+扩散系数,总体和电荷转移电阻降低.
结论:
- 4+兴奋剂有效地改善了用于离子电池的P2型Na2/3Mn2/3Ni1/3O2的电化学特性.
- 兴奋剂诱导的结构修改导致增强的速度能力,循环稳定性和离子动力学.
- 这项研究验证了Ti-doped P2型氧化物作为下一代离子电池的有希望的阴极材料.
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