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A Raman microscopy study of lithium intercalation into the graphite electrode of a lithium-ion battery is presented. An in situspectro-electrochemical cell was designed for direct observation of the electrode/electrolyte interface. The performance of this cell is discussed in terms of the results of a calibration experiment performed at a single defined point on the electrode surface. The electrode was made of TIMREX SFG 44 synthetic graphite with polyvinylidene fluoride binder. The electrolyte was lithium perchlorate, LiClO4, dissolved in a mixture of ethylene carbonate and dimethyl carbonate. In the region of the carbonyl stretching vibrational modes of the electrolyte components, changes in the band profile have been observed. At electrode potentials negative to 180 mV vs. Li/Li+, a new band evolved at about 1850 cm−1. This band has tentatively been assigned to a complex between lithium ions and decomposition products of the ethylene carbonate electrolyte component. The maximum intensity of this new band is observed at 5 mV vs. Li/Li+; its intensity decreases with increasing potential upon lithium de-intercalation. Raman mapping of the graphite electrode under potentiostatic conditions indicates that lithium intercalation does not proceed homogeneously over the graphite electrode surface at a potential of 200 mV vs. Li/Li+. An additional Raman mapping study was performed under galvanostatic conditions. With this method, the presence of “blind spots” on the electrode surface can be detected. These points lag behind in the process of lithium intercalation. Furthermore, information on changes in the carbon component of the electrode can be inferred from these measurements.

An experimental setup has been developed for the measurement of Raman spectra with NIR excitation, which combines high resolution with multichannel detection. The instrument is based on a Ti:sapphire laser for excitation, a double monochromator, and a CCD detector. The scanning multichannel technique is used for efficient acquisition of Raman spectra. Principal features of the software designed for control of the spectrometer are described, including definition of problem-adapted resolution elements and spike-removal routines. Raman spectra of several compounds are given, demonstrating the good resolution obtainable with this version of NIR Raman spectroscopy.

Two of the most significant microscopy milestones that were achieved in the last century were the imaging of individual atoms and the identification of individual atoms. Both these remarkable achievements were due to Prof. E. W. Miiller and members of his group at Pennsylvania State University. Almost fifty years ago, Miiller introduced a new type of microscope in which a sharp needle-shaped specimen was pointed at a fluorescent screen, Fig. 1. By applying an appropriately high positive voltage to the specimen, image gas atoms near the apex of the specimen could be ionized and radially projected towards the screen where they produced highly magnified images of the specimen surface, Fig. 2. By cryogenically cooling the specimen and using helium as the image gas, the first images of individual atoms were obtained in a field ion microscope by Bahadur and Müller on October 11th, 1955.

The Atom-Probe Field Ion Microscope was introduced in 1967 at the 14th Field Emission Symposium in Gaithersburg, Maryland. The Atom-Probe was, and remains, the only instrument capable of determining “the nature of one single atom seen on a metal surface and selected from neighboring atoms at the discretion of the observer”. The development of the Atom-Probe is a story that highlights Erwin Muller's strong and sometimes volatile personality. It is a story of an instrument that one NSF proposal reviewer called “impossible” because “single atoms could not be detected”. It is also the story of the Field Emission Laboratory at Penn State in the late 1960s and the contributions of two superb technicians, Gerald Fowler and Brooks McLane, and two graduate students, Douglas Barofsky and John Panitz. The anecdotes from this time are colorful and reflect Erwin's pedigree as Gustav Hertz's student in the Berlin of the 1930s.

The Atom-Probe Field Ion Microscope was introduced in 1967 at the 14th Field Emission Symposium in Gaithersburg, Maryland. The Atom-Probe was, and remains, the only instrument capable of determining “the nature of one single atom seen on a metal surface and selected from neighboring atoms at the discretion of the observer”. The development of the Atom-Probe is a story that highlights Erwin Muller's strong and sometimes volatile personality. It is a story of an instrument that one NSF proposal reviewer called “impossible” because “single atoms could not be detected”. It is also the story of the Field Emission Laboratory at Penn State in the late 1960s and the contributions of two superb technicians, Gerald Fowler and Brooks McLane, and two graduate students, Douglas Barofsky and John Panitz. The anecdotes from this time are colorful and reflect Erwin's pedigree as Gustav Hertz's student in the Berlin of the 1930s.