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Nanostructure Characterisation by Electron Beam Techniques
Electron beam induced changes in Auger electron spectra for Lithium ion
battery materials
M. Hoffmann, 1,2* S. Oswald, 1 and J. Eckert 1,2
1 IFW Dresden, PF 270116, D-01171 Dresden, Germany
2
TU Dresden, Institut für Werkstoffwissenschaft, D-01062 Dresden, Germany
*m.hoffmann@ifw-dresden.de
The so called solid electrolyte interphase (SEI) [1], a thin film on top of the electrodes of common lithium
ion batteries has an important role for the lifetime and the performance of such cells. Due to its surface and
chemical sensitivity the state of the art tool for investigations of this layer is the X-ray photoelectron
spectroscopy (XPS). Since the SEI can consist of several different organic and inorganic compounds with a
size down to some nm [2], a technique with the same surface and almost the same chemical sensitivity but a
high spatial resolution would be very desirable. In this work we try to apply Auger electron spectroscopy
(AES) to this field of lithium based materials.
The different excitation by electrons in AES in contrast to X-rays in XPS leads to several problems for the
detection of lithium compounds in the SEI. Most of the SEI components are not conductive, so the effects of
charging are commonly the biggest ones. In addition the electron beam can cause a change and a damage of
the sample surface [3]. In this work we performed a lot of reference experiments measuring pure lithium,
lithium compounds and reaction products of lithium with common electrolyte ingredients, regarding their
stability and their distinctness in AES analysis.
References
[1] P. B. Balbuena, Y. Wang, Lithium-Ion Batteries: Solid-Electrolyte Interphase, Imperial College Press
(2004)
[2] E. Peled, D. Golodnitsky, G. Ardel, J. Electrochem. Soc. 144 (1997), L208
[3] C. G. Pantano, T. E. Madey, Applied Surface Science 7 (1981), 115-141
Funding by “Pakt für Forschung und Innovation” is acknowledged
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