Analytical dissection of an automotive Li-ion pouch cell

Information derived from microscopic images of Li-ion cells is the base for research on the function, safety and degradation of Li-ion batteries. This research was carried out to acquire information required to understand the mechanical properties of Li-ion cells. Parameters such as layer thicknesses, material compositions and surface properties play important roles in the analysis and further development of Li-ion batteries. In this work, relevant parameters were derived using microscopic imaging and analysis techniques. The quality and usability of the measured data, however, are tightly connected to the sample generation and preparation methods used and the measurement device selected. Differences in specimen post-processing methods and measurement setups contribute to variability in the measured results. In this paper, the complete sample preparation procedure and analytical methodology are described, variations in the measured dataset are highlighted and the study findings are discussed in detail. The presented results were obtained from an analysis conducted on a state-of-the-art, Li-ion pouch cell applied in an electric vehicle that is currently commercially available.