通过液相传输电子显微镜直接观察 Li-O2 电池的反氧介质辅助溶液相放电
Donghoon Lee1, Hyeokjun Park1, Youngmin Ko1
1Center for Nanoparticle Research , Institute for Basic Science , Seoul 08826 , Republic of Korea.
Journal of the American Chemical Society
|May 9, 2019
概括
研究人员使用现场TEM观察氧 (Li-O2) 电池放电. 他们揭示了过氧化物 (Li2O2) 形成的两步生长机制,这对于推进高能量密度电池至关重要.
科学领域:
- 电化学
- 材料科学
- 能量储存
背景情况:
- 氧 (Li-O2) 电池具有较高的理论能量密度,这是下一代储能的主要目标.
- 由于放电产品的形成而导致过早的空气电极被动化会阻碍2电池的性能.
- 用于增强电荷转移和减轻被动化问题.
研究的目的:
- 用氧化还原介质阐明氧电池中的放电机制.
- 提供对过氧化物 (Li2O2) 形成的实时机械洞察.
- 引导新型氧化还原介质的合理设计,以提高氧电池的性能.
主要方法:
- 在现场使用液相传递电子显微镜 (TEM) 进行实时监测.
- 使用氧化还原介质对Li-O2电池进行了电化学放电.
- 对Li2O2生长特征进行了定量分析.
主要成果:
- 直接在现场进行的TEM观察显示,状Li2O2排放产品的数量逐渐增加.
- 2O2增长机制被确定为一个两步过程.
- 早期的Li2O2生长的特征是横向扩张成盘状结构,随后是垂直生长和形形态转变.
结论:
- 了解Li2O2形成机制对于推进Li-O2电池技术至关重要.
- 观察到的两步增长机制为排放产品的演变提供了基本的见解.
- 这项研究为设计更有效的氧化还原介质和优化氧电池性能铺平了道路.
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