Meaning
Iterative propagation of pixel intensities within a constrained spatial domain allows for the selective expansion of image features without crossing predefined boundaries. Implementing geodesic dilation limits the growth of a marker image to the region defined by a mask image. This morphological operation is essential for identifying interconnected pore networks in battery electrodes.
By masking the expansion, only pores that connect to a source region are highlighted.
Morphological Constraint
Unlike standard dilation, this operation requires two input images. During geodesic dilation, the standard dilation of the marker is intersected with the mask at each step. This constraint prevents bleeding.
Connectivity Extraction
Calculating the tortuosity of the liquid phase requires identifying the continuous pore pathways that run from one side of the electrode to the other. Geodesic dilation helps extract these pathways by setting the starting surface as the marker and the entire pore space as the mask. The operation run to completion reveals the percolating network of pores that are active for ionic conduction.
This network is what carries the lithium ions during cell operation, and its volume determines the high-rate performance of the system.
Electrode Evaluation
Product designers use the results of this morphology analysis to assess the rate capability of new electrode designs. When geodesic dilation shows a high fraction of isolated pores, the design is altered to improve the slurry formulation. Sourcing engineers use the metric to compare different carbon additive distributions.
This helps select the most conductive option.
