耐用的碳涂层Li2(S) 核心外球体,用于高性能/硫电池
Caiyun Nan1, Zhan Lin, Honggang Liao
1Department of Chemical and Biomolecular Engineering, University of California , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|March 4, 2014
概括
研究人员开发了稳定的碳涂层硫化 (Li2S@C) 核心外颗粒. 这一创新增强了硫化的.
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
- 纳米技术 纳米技术
背景情况:
- 硫化 (Li2S) 具有很高的理论容量,使其成为一个有前途的阴极材料.
- 由于周期寿命和速率能力较差,Li2S的实际应用受到阻碍.
- 开发稳定的基于Li2S的阴极对于先进的能量存储至关重要.
研究的目的:
- 为了合成大小控制的硫化球.
- 使用化学蒸汽沉积 (CVD) 创建稳定的碳涂层硫化核心外 (Li2S@C) 颗粒.
- 为了评估新型Li2S@C阴极材料的电化学性能.
主要方法:
- 控制尺寸的Li2S球体的合成.
- 化学蒸汽沉积 (CVD) 用于碳涂层.
- 对Li2S@C复合材料正极的电化学测试.
主要成果:
- 成功合成了具有保护性和导电性碳外的Li2S@C核心外颗粒.
- 在0.2C时达到972 mAh g-1 Li2S (1394 mAh g-1 S) 的高初始放电容量.
- 在0.5°C的400个循环后,表现出稳定的循环性能,形态变化最小,即使含有高Li2S含量 (88 wt%).
结论:
- 碳涂层Li2S@C核心外颗粒显著提高了循环寿命和速率能力.
- 开发的Li2S@C材料显示出在高性能离子电池中实际应用的潜力.
- 这种方法为稳定高容量正极材料提供了一个可行的策略.
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