Methods and Instruments | Scanning Electronic Microscopy

Scanning Electron Microscopy (SEM) principles are introduced and some applications to the characterization of electrochemical power sources are presented. The general features of a SEM microscope are briefly described with particular attention to: (i) generation and focusing of the electron beam over the samples; (ii) interactions between electrons and atoms in the sample producing the analytical signals; (iii) detection and recording of secondary or backscattered electrons for image reconstruction; (iv) detector of X-rays and electron probe microanalysis. Some applications of the technique in the field of electrochemical storage devices are summarized, with the aim of shedding light onto the relationships between morphology/composition and electrochemical behavior of electrodes. Finally, an outlook on recent methodologies is given, such as environmental SEM which, operating under moderate pressures, allows in situ monitoring of chemical and morphological transformations related to electrochemical power sources.