基于石榴石的固态电池具有高表面积的多孔LLZO膜
Huanyu Zhang1,2, Faruk Okur1,2, Bharat Pant3
1Laboratory for Thin Films and Photovoltaics, Empa─Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
ACS applied materials & interfaces
|March 4, 2024
概括
研究人员开发了一种新方法,为固态电池制造多孔-7氧化 (LLZO) 膜. 这项创新提高了离子电池的稳定性,通过防止空隙形成和树生长,为更安全,高能储存铺平了道路.
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
- 固态电池 固态电池是什么
背景情况:
- 基于石榴石的固态电池,使用Li7La3Zr2O12 (LLZO),提供非易燃,高能量密度的存储.
- 在LLZO/Li接口上形成空隙阻碍了商业化,导致树的生长和在实际电流密度下循环稳定性差.
- 开发薄的LLZO电解质对于实现这些电池的高能量密度至关重要.
研究的目的:
- 解决基于石榴石的固态电池中空隙形成和树石问题.
- 开发一种用于薄,多孔的LLZO膜的简单制造方法.
- 为了提高固态电池的循环稳定性和能量密度.
主要方法:
- 使用小孔形成器 (约50微米厚) 制造独立的,多孔的LLZO膜. 1.5 微米). 这是一个很大的问题.
- 采用超快速烧结,加热/冷却速度快 (大约2分钟) 50°C/s) 来控制多孔性,防止过度密集.
- 包括毛孔大小在内的特征性膜性质 (约. 2.3微米),多孔度 (51%) 和特定表面积 (1.3微米-1).
主要成果:
- 实现了对LLZO膜 (1.3μm-1) 报告的最高特定表面积.
- 多孔的LLZO膜显著增加了Li/LLZO接触面积,有效地减轻了空隙形成.
- 在一个对称的Li/LLZO/Li细胞中表现出异常的循环稳定性,在0.1 mA cm-2下超过600小时.
结论:
- 开发的方法提供了一个简单的方法来制造有孔的LLZO膜,用于先进的固态电池.
- 增加的接触面积和减轻空隙形成有助于增强循环稳定性.
- 这项工作为高能量密度,安全的石榴石基固态电池的商业化提供了有前途的途径.
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