Electron Microscopy-Based 3D Structural Analysis
Materials are inherently three-dimensional, yet most electron microscopy techniques yield 2D projections that cannot fully capture critical information such as pore connectivity, crack geometry, and interface morphology. AEML reconstructs the three-dimensional structure of complex materials using STEM tomography and FIB-SEM serial sectioning. The resulting 3D datasets contribute to the structural design of next-generation battery electrodes and to failure analysis.
Techniques
STEM Tomography
By acquiring a tilt series of HAADF-STEM images (typically ±70°), we reconstruct 3D volumes of nanostructures with sub-nanometer resolution. The Talos F200X with its SuperX EDS detector enables simultaneous 3D chemical mapping through EDS tomography — revealing not just morphology but elemental distribution in three dimensions.
FIB-SEM Serial Sectioning
For larger volumes (cubic micrometers to hundreds of cubic micrometers), we use focused ion beam milling combined with SEM imaging to serially section specimens. This approach bridges the gap between TEM-scale resolution and the larger length scales relevant to electrode architecture and failure analysis.
Cryo-Transfer for Air-Sensitive Materials
Many of the materials we study — solid electrolytes, Li metal anodes, sulfide-based composites — degrade upon air exposure. Using the Mel-Build DCT cryo-transfer holder with vacuum transfer capability, we maintain specimens under protective conditions throughout the entire preparation and imaging workflow, ensuring that what we observe reflects the material’s true state.
Applications
- Battery electrode microstructure: 3D mapping of active material, binder, carbon additive distribution and pore connectivity in composite electrodes
- Crack and void analysis: Quantifying intragranular cracking patterns in high-Ni cathode particles after cycling
- Interface morphology: Reconstructing the 3D geometry of solid electrolyte / electrode interfaces in ASSBs
- Bio-nanomaterials: 3D structure of diatom frustules and nanoporous ceramic scaffolds (collaborative work at LBNL)
Representative Publications
- Y.-W. Byeon et al., “Conductive carbon embedded beneath cathode active material for longevity of solid-state batteries,” J. Mater. Chem. A (2024)
- K.-J. Lee et al., “Revealing crack-healing mechanism of NCM composite cathode for sustainable cyclability of sulfide-based solid batteries,” Energy Storage Mater. (2023)
- Y.-W. Byeon et al., “Electronic structure manipulation via composition tuning for development of highly conductive and acidic-stable oxides,” J. Mater. Chem. A (2022)
Equipment
- Talos F200X — (S)TEM/EDS tomography
- Glacios 2 — Cryo-electron tomography
- Mel-Build DCT — Double tilt cryo-transfer holder (vacuum, -155 °C)
- Spectra Ultra (under installation) — High-resolution tomographic imaging