Transmission Electron Microscopy (TEM)
Transmission electron microscopy (TEM) passes a high-energy electron beam through an electron-transparent specimen and forms images or diffraction patterns that reveal atomic-scale crystal structure, defects, interfaces, and chemical composition via coupled EELS or EDX. As a hard skill it requires preparing specimens thin enough for electron transmission via FIB lamella or ion-milling, aligning the beam and selecting correct imaging conditions (bright-field, dark-field, HRTEM, HAADF-STEM), and interpreting lattice images and diffraction patterns against reference structures. Battery researchers apply TEM to resolve atomic-scale structural changes in cycled cathode particles, characterize SEI layer thickness and composition, and identify precipitated phases at grain boundaries in solid electrolytes.
