Investigation of Electrical and Physical Cell Parameters—A Comparative CT Study on Prismatic Battery Cells

Computed tomography (CT) imaging has proven to be effective for detecting and visualizing a wide range of inhomogeneities and defects. Applying computer vision (CV)-based image processing enables detailed feature measurements on selected CT image slices, which could be of benefit as cells of the same type often show variations in electrical properties. When combined with electrical testing, CT imaging could provide valuable insights into the battery cell, helping to identify potential sources of electrical deviations. However, it remains unclear to what extent CT-based measurements, especially for larger prismatic cells, e.g., those used in automotive applications, can explain electrical deviations aside from identifying significant or latent defects. Therefore, this study performs a correlative analysis and compares the electrical measurement results with CT-based measurements of the cell’s physical features, specifically the anode and cathode sizes. Electrical and CT measurements from ten lithium iron phosphate/graphite (LFP/C) cells of the same type are analyzed. The results indicate that while CT imaging has the potential to help identify the sources of electrical deviations, it also shows that cell-level CT measurements alone cannot fully explain electrical performance deviations. Measurement uncertainty, the potential overlapping impact of other cell features, and the actual influence of the measured physical properties on the cell’s electrical performance limit the correlation between CT-based measurements and electrical parameters.