Battery Research

An important goal of electrochemical research is the development of advanced electrode materials for rechargeable high energy batteries with a high current density and a long cycle life. In lithium-ion batteries, manganese oxides like LiMnO₂ and LiMn₂O₄ are widely used as positive electrodes. Doping these oxides with other metals like Co and Ni frequently leads to materials with improved electrochemical properties. Furthermore, other transition metal compounds like vanadium oxide nanotubes are being probed as electrode materials.

For the successful operation of Li-ion batteries, the formation of a protective surface film on the carbonaceous anode materials is essential. This solid electrolyte interphase (SEI) has also been discussed for cathode materials such as LiMn₂O₄, LiCo₂O₄, and LiNi₂O₄. For the first time, this film was directly visualized by scanning electron microscopy. So-called post mortem SEM analyses of the electrodes are suitable to gain additional information.

Enlarged view: SEM images of electrodes — Post mortem SEM images of graphite (left) and LiMn₂O₄ (right) electrodes with the SEI layers marked by arrows.

Selected Publications

Film Formation at Positive Electrodes in Lithium-Ion Batteries
A. Würsig, H. Buqa, M. Holzapfel, F. Krumeich, and P. Novák
Electrochem. Solid-State Letters 8 (2005) A34-A37 external page DOI

Stabilisation of Lithiated Graphite in an Electrolyte Based on Ionic Liquids: an Electrochemical and Scanning Electron Microscopy Study
M. Holzapfel, C. Jost, A. Prodi-Schwab, F. Krumeich, A. Wuersig, H. Buqa, and P. Novák
Carbon 43 (2005) 1488-1498 external page DOI

Niobium(V) Oxynitride: Synthesis, Characterization, and Feasibility as Anode Material for Rechargeable Lithium-Ion Batteries
X.-J. Wang, F. Krumeich, M. Wörle, Reinhard Nesper, L Jantsky, and H. Fjellvåg
Chem. Eur. J. 2012, 18, 5970 – 5978 external page DOI

Investigation of Nano-Fibrous Selenium and its Polypyrrole and Graphene Composite as Cathode Material for Rechargeable Li-Batteries
D. Kundu, F. Krumeich, and R. Nesper
J. Power Sources 226 (2013) 112-117 external page DOI

Nanocomposite of Manganese Ferrocyanide and Graphene: A Promising Cathode Material for Rechargeable Lithium Ion Batteries
X.-J. Wang, F. Krumeich, and R. Nesper
Electrochem. Commun. 34 (2013) 246–249 external page DOI

New High Capacity Cathode Materials for Rechargeable Li-Ion Batteries: Vanadate-Borate Glasses
S. Afyon, F. Krumeich, C. Mensing, A. Borgschulte, and R. Nesper
Sci. Rep. 4 (2014) 7113 external page DOI, see also: ETH life