The Ultrafast Laser Ablation of Li(Ni0.6Mn0.2Co0.2)O2 Electrodes with High Mass Loading
The Ultrafast Laser Ablation of Li(Ni0.6Mn0.2Co0.2)O2 Electrodes with High Mass Loading
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DOI：
10.3390/app9194067
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发表时间：
2019-10-01
影响因子：
2.7
通讯作者：
Pfleging, Wilhelm
中科院分区：
文献类型：
--
作者：
Zhu, Penghui;Seifert, Hans Juergen;Pfleging, Wilhelm
近年来，锂离子电池已成为最有前途的储能装置。然而，能量密度和功率密度的同时提高仍然是一个巨大的挑战。电极的超快激光结构化通过改善锂离子扩散动力学来提高锂离子电池的功率密度是可行的。以Li（Ni0.6Mn0.2Co0.2）O2（NMC 622）为阴极材料，研究了激光加工方式和薄膜厚度对倍率性能和能量密度的影响。制备厚度为91 μ m至250 μ m的NMC 622电极，同时施加间距为200 μ m至600 μ m的线图案。NMC 622阴极使用纽扣电池设计与锂相对组装。与具有非结构化阴极的电池相比，具有结构化的91 μ m厚的膜阴极的电池在C-倍率3C下显示出较小的容量损失。具有250 μ m厚的膜阴极的电池在高达C/5的低C倍率下显示出较高的放电容量，并且结构化阴极在高达1C的C倍率下显示出较高的放电容量。然而，放电容量恶化与更高的C率。激光产生的图案和电极厚度的适当选择取决于所要求的电池应用场景;即，充电/放电速率和比/体积能量密度。
Lithium-ion batteries have become the most promising energy storage devices in recent years. However, the simultaneous increase of energy density and power density is still a huge challenge. Ultrafast laser structuring of electrodes is feasible to increase power density of lithium-ion batteries by improving the lithium-ion diffusion kinetics. The influences of laser processing pattern and film thickness on the rate capability and energy density were investigated using Li(Ni0.6Mn0.2Co0.2)O-2 (NMC 622) as cathode material. NMC 622 electrodes with thicknesses from 91 mu m to 250 mu m were prepared, while line patterns with pitch distances varying from 200 mu m to 600 mu m were applied. The NMC 622 cathodes were assembled opposing lithium using coin cell design. Cells with structured, 91 mu m thick film cathodes showed lesser capacity losses with C-rates 3C compared to cells with unstructured cathode. Cells with 250 mu m thick film cathode showed higher discharge capacity with low C-rates of up to C/5, and the structured cathodes showed higher discharge capacity, with C-rates of up to 1C. However, the discharge capacity deteriorated with higher C-rate. An appropriate choice of laser generated patterns and electrode thickness depends on the requested battery application scenario; i.e., charge/discharge rate and specific/volumetric energy density.