Development of 3D model electrodes with hybrid manufacturing processes (3D-Bat-Hybrid)

在该项目的框架内，正在开发和评估具有新型三维电极结构的硅/石墨(Si/C)负极材料。通过结合激光烧蚀和激光打印(Lift，激光诱导前向转移)，三维微结构和材料排列将在具有不同质量载荷的模型系统中表示。使用电化学方法(循环电池测试、恒电流间歇滴定技术、电化学阻抗谱、循环伏安法)和激光诱导击穿光谱(LIBS)对新的3D电极结构的电化学特性进行了量化，并识别了可能的老化现象，以创建Si/C阳极结构的优化设计概念。通过加法和减法相结合的方法实现的电极结构和锂扩散路径对电化学性能的影响被定量地记录下来，并在Ragone图中根据电化学性能进行分类。目前正在致力于以下科学目标：1.开发阳极层厚度在30-150微米~2范围内，硅比例在5-50wt.%范围内的Si/C阳极。工艺参数、微观结构和由此产生的电化学性质的相关性3。通过根据可实现的能量和功率密度对电极结构的电化学特性进行分类，获得对结构-性能关系的基本了解(拉根图)4.将结构-性能关系转移到具有有效传输参数的电池模型(COMSOL®)(Newman方法“P4D”)5.从材料和微结构特征的影响识别和评估电池退化机制(化学、机械)。为该项目选择了一种基于激光的科学方法来抵消局部诱导的机械应力和变形引起的Si/C阳极退化。这是通过引入三维排列的活性材料(石墨和硅)来实现的，这些材料嵌入在3D地形中，具有高硅质量比例。由于3D电极结构的活性表面扩大，电荷转移电阻和扩散过电位降低，这对于大充放电电流是很重要的。这一新方法有助于开发功率更高、倍率能力更高、寿命更长的锂离子电池储能材料。

In frame of the project, silicon/graphite (Si/C) anode materials with novel 3D electrode architectures are being developed and evaluated. By combining laser ablation and laser printing (LIFT, laser-induced forward transfer), three-dimensional microstructures and material arrangements are to be represented in model systems with different mass loadings. Using electrochemical methods (cyclic cell tests, galvanostatic intermittent titration technique, electrochemical impedance spectroscopy, cyclic voltammetry) and laser-induced breakdown spectroscopy (LIBS), the electrochemical characteristics are quantified for the new 3D electrode architectures and possible aging phenomena are identified in order to create optimized design concepts for Si/C anode architectures. The influence of the electrode architectures and lithium diffusion pathways realized through a combination of additive and subtractive structuring methods on the electrochemical characteristics is recorded quantitatively and classified in Ragone diagrams with regard to the electrochemical performance.The following scientific goals are being worked on:1. Development of Si/C anodes with Si proportions in the range of 5-50 wt.% for anode layer thicknesses in the range of 30-150 µm2. Correlation of process parameters, microstructure and the resulting electrochemical properties3. Obtaining a basic understanding of the structure-property relationships by classifying the electrochemical characteristics of electrode architectures with regard to achievable energy and power densities (Ragone diagram)4. Transfer of the structure-property relationships to a cell-based battery model (Comsol®) with effective transport parameters (Newman approach "P4D")5. Identification and evaluation of the cell degradation mechanisms (chemical, mechanical) with regard to the influences of material and microstructure characteristics.A laser-based scientific approach was chosen for the project to counteract Si/C anode degradation caused by locally induced mechanical stresses and deformations. This is to be achieved by introducing three-dimensionally arranged active materials (graphite and silicon), embedded in 3D topographies, with a high Si mass proportion. Due to the enlarged active surface of the 3D electrode structure, charge transfer resistance and diffusion overpotential are reduced, which is important for high charge and discharge currents. This new method is helping to develop energy storage materials for lithium-ion batteries with enhanced power, high rate capability, and longer lifetime.