Identical Location SEM/FIB Characterization
Correlating microstructural features across length scales is essential for understanding grain refinement, phase transformations, and defect evolution in severely deformed materials. Identical-location SEM/FIB/TEM characterization tracks the exact same region throughout the workflow, providing unambiguous, site-specific insight into microstructural evolution, motivating its use wherever bulk or randomly-sampled characterization cannot resolve the underlying mechanisms.
Identical location SEM-EBSD studies on Al anodes
The microstructure of electrode materials strongly influences battery performance by governing ion transport, reaction kinetics, and morphological evolution during cycling. Understanding these effects is particularly important for Al-ion batteries, where electrode stability remains a key challenge
In this work, we investigated the deposition and stripping behavior of aluminum in symmetric Al/EMIMCl:AlCl₃/Al cells using high-purity (99.999%) electropolished aluminum electrodes. To directly correlate surface changes with the underlying microstructure, electrodes were characterized before and after a single deposition–stripping cycle using identical-location SEM, backscattered electron (BSE) imaging, and EBSD orientation mapping. At a deposition capacity of 100 mA·s·cm⁻², aluminum formed randomly distributed particles (~2 μm) without a clear dependence on substrate microstructure. Increasing the deposition capacity to ~10,000 mA·s·cm⁻² produced larger particles (~25 μm) and led to the formation of a continuous aluminum layer covering the surface. In contrast, aluminum stripping exhibited a strong microstructure dependence. At 2.5 × 10³ mA·s·cm⁻², preferential pit formation and localized etching occurred at high-angle grain boundaries (θ > 15°). Grains with (001) orientation showed enhanced resistance to dissolution. At higher stripping capacities (~10,000 mA·s·cm⁻²), surface morphology became strongly orientation-dependent: (001)-oriented grains remained comparatively smooth with circular pits, while other orientations developed pronounced roughness and directional striations. These results identify aluminum stripping as the dominant driver of surface roughening during electrochemical cycling. The strong dependence of stripping behavior on crystallographic orientation and grain boundary structure highlights the critical role of electrode microstructure in determining electrode stability. This work provides new insights into degradation mechanisms in aluminum metal electrodes and offers guidance for the development of more durable Al-ion batteries.