1. Helmholtz-Institute Ulm (HIU) for Electrochemical Energy Storage, Helmholtzstr. 11, 89081 Ulm, Germany
2. Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021 Karlsruhe, Germany
3. Institute of Electrochemistry, Ulm University, Albert-Einstein-Allee 47, D-89081 Ulm, Germany
4. Faculty of Physical Sciences, University of Iceland VR-III, 107 Reykjavk, Iceland