实现超高能量密度的电池:通过控制的阴离子干扰消除不可逆转的阳离子还氧化
Minjun Wang1,2,3, Changming Ke4,5, Han Zhang2,3
1Institute of Zhejiang University-Quzhou, Zheda Road 99, Quzhou 324000, China.
Nano letters
|September 16, 2024
概括
富层氧化物 (LLOs) 的一种新的低电位激活方法可以防止在初始充电时释放氧气. 这种方法增强了LLOs,以提高电池性能和稳定性.
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:
- 富的分层氧化物 (LLOs) 是有前途的阴极材料,因为它们的高能量密度,支持阴离子和阴离子的氧化还原.
- 然而,LLOs在高压初始充电过程中遭受氧气演变引起的显著容量损失和结构不稳定.
研究的目的:
- 开发一种抑制氧气演变的方法,并提高LLOs的电化学性能.
- 精确控制过渡金属层中的阴离子排序,以提高稳定性.
主要方法:
- 对LLOs应用了一种简单的低电位激活 (LOWPA) 方法.
- 稳定的电解质与LOWPA方法一起使用.
- 该方法控制了过渡金属层的顺序变异.
主要成果:
- 通过LOWPA方法,产生了一个平面内阴离子失序的Li1.2Mn0.54Co0.13Ni0.13O2结构.
- 通过稳定Mn-O2或Mn-O3物种,可以避免4.8V的不可逆转的氧气演变.
- 实现了322 mAh g-1的超高可逆容量,91.5%的初始库伦比克效率,增强的耐用性和速率能力.
结论:
- LOWPA方法有效地抑制氧气演变,并提高LLO性能,而不会改变化学成分.
- 这种方法提供了一个简单的模型,用于理解LLOs中的氧-氧化化学.
- 开发的LLOs表明了先进电池应用的潜力.
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