Hierarchical structuring of cathodes and anodes for lithium-ion batteries

Extensive technological progress is essential to meet the ambitious future requirements of energy storage devices. This is due to the necessity of achieving high energy and power density operations, accompanied by high safety standards and extended lifespans, while maintaining low production and material costs. Significant importance is placed on the research of high energy active materials. However, besides material optimization, there is substantial potential for optimization by introducing electrodes with high mass loading, advanced electrode architectures, and their transfer to production level. Achieving appropriate trade-offs between high energy and power density, process reliability, and economic considerations poses a challenge for current lithium-ion battery technology. For this purpose, the laser-assisted generation of three-dimensional (3D) electrode architectures is studied and evaluated. Advanced electrode design incorporates micro and sub-micron structures that can be designed in various ways. Significant improvements in battery lifespan and high-power operation capabilities can be achieved compared to traditional two-dimensional (2D) electrodes. Furthermore, the production of 3D electrodes with laser processing requires coordination with other established manufacturing steps in the battery production process. In particular, the calendering of electrodes holds great importance as it has a significant impact on the microstructural properties of the composite electrode, including porosity, material density, and film adhesion strength. This study investigated the impact of laser-induced hierarchical structuring, comprising micro-/nano-porosities and microtopography, on electrodes with varying mass loadings from 2 mAh/cm² to 6 mAh/cm². In this regard, cells comprising graphite anodes and lithium-nickel-manganese-cobalt oxide cathodes were prepared and subjected to electrochemical characterization techniques.