在高能量密度单晶NCA电极中通过多晶混合设计增强电气连接
Yuntaek Oh1,2, Hwiho Kim1, Jongbeom Lim1
1Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
ACS applied materials & interfaces
|May 5, 2025
概括
单晶阴极由于粒子之间的连接不好,表现不佳. 添加一些较大的多晶颗粒可以改善这些连接,提高电池速率的能力.
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
- 电池技术 电池技术
背景情况:
- 单晶 (SC) 富含Ni的阴极比多晶 (PC) 提供更好的稳定性,但速度能力较低.
- 这种SC阴极的限制通常归因于粒子间连接性差或扩散缓慢,主要原因不明.
- 很难根据电气连接或扩散量化电极利用率.
研究的目的:
- 确定SC Ni-丰富的阴极中速度能力差的主要原因.
- 研究粒子间连接与扩散对电极性能的影响.
- 制定提高SC电极速度能力的策略.
主要方法:
- 电化学分析以评估电池性能.
- 46点探头电阻测量用于量化电接触电阻.
- 基于同步离子的传输X射线显微镜 (TXM) 使用成像可视化电极利用.
主要成果:
- SC电极的低速率能力主要是由于粒子间连接性较差造成的.
- 结合PC颗粒可以显著降低电接触电阻.
- 较大的颗粒大小进一步增强了电极连接,提高了整体性能.
结论:
- 混合一小部分大型PC颗粒有效地提高了SC电极的速率能力.
- 在SC和PC颗粒之间改善的电接触提高了电气连接.
- TXM成像证实了在高循环速度下增强的粒子利用率和性能.
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