高功率和高容量的电极用于可充电电池
Kisuk Kang1, Ying Shirley Meng, Julien Bréger
1Center for Materials Science and Engineering and Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
概括
研究人员通过修改,和氧化物来提高可充电电池的充电和放电率. 与当前的氧化电池相比,这种新材料表现出优越的性能,有利于电动汽车和动力备份系统.
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
- 计算建模 计算建模
背景情况:
- 具有高能量密度和快速充/放电率的可充电电池对于混合动力电动汽车和电源备份等应用至关重要.
- 尼克氧化物[Li{\Ni{\0.5}Mn{\0.5}) O2]是一种安全且具有成本效益的材料,但其内在速率能力被认为很差.
- 氧化 (LiCoO2) 是电池电极的当前标准.
研究的目的:
- 通过计算建模,确定设计更高速率电池电极的策略.
- 通过修改其晶体结构来提高-氧化的速率能力.
- 为了比较改性-氧化与氧化的性能.
主要方法:
- 利用初始计算建模来探索电极设计策略.
- 修改了,和氧化物的晶体结构.
- 测试了修改材料的速度能力.
主要成果:
- 确定了提高电池电极速率能力的有效策略.
- 在改性,,氧化物中实现了意想不到的高速率能力.
- 证明性能优于氧化.
结论:
- 晶体结构的修改是一种可行的策略,可以显著提高,和氧化物的速率能力.
- 改性--氧化物为高速电池应用提供了-氧化物的有希望的替代品.
- 这项研究为设计用于苛刻应用的先进电池材料开辟了新的途径.
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