Increasing energy capacity, power density and cycle life of Li-ion batteries requires optimizing the composite electrodes microstructure. 3D simulation analysis and modeling have shown that the amount, the size, the shape, the tortuosity and the specific surface area of pores and particles are all key parameters for the improvement of electrode performance.

Recently, the 3D morphologies of various anodes and cathodes for Li-ion batteries have been evaluated by FIB/SEM and X-Ray Computed Tomography (XRCT). In addition, 3D imaging softwares allow automatic processing and quantifying measurements by finite element calculations or other numerical models. XRCT is non destructive but routine procedures are limited to rather poor spatial resolution. Combined Focused Ion Beam (FIB) and Scanning Electron Microscopy (SEM) is destructive but has recently emerged as an established technique for the three-dimensional imaging at high spatial resolution, inaccessible with laboratory X-ray tomography. Electron TEM tomography is finally an option to improve the spatial resolution down to several nanometers.

This paper will give examples of different materials used for Li-ion  battery electrodes, analyzed at different scales with all these different 3D tomography techniques. It will be shown that static characterisation of the prestine materials gives the initial morphology of the electrodes.

Samples can then be analysed after electrical cycling and this shows the degradation mechanisms. Some methods even allow to do the observation in operado.

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EMC Abstracts - https://emc-proceedings.com/abstract/multi-scale-tomography-of-materials-for-li-ion-battery-electrodes/