晶体结构和电子特性对人工石墨的储存性能的影响
Zhiwei Liu1, Yang Shi1, Qinghe Yang1
1Research Institute of Petroleum Processing, SINOPEC Beijing 100083 PR China niehong.ripp@sinopec.com.
RSC advances
|October 16, 2023
概括
这项研究揭示了人工石墨是如何形成的.
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
- 固态物理 固态物理
背景情况:
- 石墨是离子电池 (LIB) 的主要阳极材料.
- 了解人工石墨的晶体结构和电子特性对于提高阳极性能至关重要.
- 目前的研究重点是优化石墨的电化学行为,以更好地储存能量.
研究的目的:
- 研究人工石墨的晶体结构与其在LIBs中的电化学性能之间的关系.
- 开发一种方法,以质量评估石墨阳极中的离子导电性.
- 根据固态理论阐明石墨中储存的机制.
主要方法:
- 合成不同晶体结构的石墨样本.
- 合成石墨作为LIB阳极的电化学测试.
- 离子导电性的定性评估.
- 使用固态理论进行分析.
主要成果:
- 石墨具有更大的晶体平面和更少的堆叠层,具有更高的电子导电性 (σe).
- 较小的晶体平面 (La) 和较高的堆叠 (Lc) 的石墨显示出更高的离子导电率 (σLi),由较低的初始充/放电电压表明.
- 电子导电性在低充/放电速率下主导容量,而离子导电性在更高速率下变得至关重要.
结论:
- 人工石墨的电化学性能与其晶体结构以及由此产生的电子和离子导电性密切相关.
- 优化晶体平面尺寸和堆叠层可以根据特定的充电/放电率要求量身定制石墨阳极.
- 这些发现为设计用于改进LIB的先进石墨阳极材料提供了洞察力.
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