Meaning
Three dimensional imaging methodology combining focused ion beam milling with scanning electron microscopy to reconstruct material microstructure. The application of fib-sem tomography provides a detailed view of the internal arrangement of particles and pores within a battery electrode. It uses a sequence of slicing and imaging steps to build a high resolution data set.
Spatial Resolution
Voxel sizes in the resulting model depend on the beam spot size and the slice thickness. Because fib-sem tomography offers nanometer scale precision, it captures the thin interface between the active material and the binder. This level of detail is necessary for modeling transport properties in complex composite structures.
Volume Reconstruction
Software tools align the individual two dimensional images to create a continuous solid model. Through fib-sem tomography, engineers calculate the tortuosity and connectivity of the pore network. These geometric factors directly influence the rate at which ions move through the liquid electrolyte during fast charging.
Damage Mechanism
Ion beam interaction can introduce heat or implantation artifacts into sensitive samples. During the execution of fib-sem tomography, careful current selection prevents the melting of polymer binders or the phase change of volatile components. Monitoring the beam current ensures the digital twin accurately represents the physical state of the manufactured cell.
Experienced operators adjust the milling parameters for every unique sample type to ensure that the data remains defensible and accurate. This careful control allows for the reliable quantification of the internal geometry.
