title: Suppression of Aluminum Current Collector Dissolution by Protective Ceramic Coatings for Better High-Voltage Battery Performance.
abstract: Batteries based on cathode materials that operate at high cathode potentials, such as LiNi0.5Mn1.5O4(LNMO), in lithium-ion batteries or graphitic carbons in dual-ion batteries suffer from anodic dissolution of the aluminum (Al) current collector in organic solvent-based electrolytes based on imide salts, such as lithium bis(trifluoromethanesulfonyl) imide (LiTFSI). In this work, we developed a protective surface modification for the Al current collector by applying ceramic coatings of chromium nitride (CrxN) and studied the anodic Al dissolution behavior. By magnetron sputter deposition, two different coating types, which differ in their composition according to the CrN and Cr2N phases, were prepared and characterized by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and their electronic conductivity. Furthermore, the anodic dissolution behavior was studied by cyclic voltammetry and chronocoulometry measurements in two different electrolyte mixtures, that is, LiTFSI in ethyl methyl sulfone and LiTFSI in ethylene carbonate/dimethyl carbonate 1:1 (by weight). These measurements showed a remarkably reduced current density or cumulative charge during the charge process, indicating an improved anodic stability of the protected Al current collector. The coating surfaces after electrochemical treatment were characterized by means of SEM and XPS, and the presence or lack of pit formation, as well as electrolyte degradation products could be well correlated to the electrochemical results.
authors.affiliation: University of Münster, MEET Battery Research Center, Institute of Physical Chemistry, Corrensstrasse 46, 48149, Münster, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Heckmann
authors.affiliation: Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, Materials Synthesis and Processing (IEK-1), 52425, Jülich, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Krott
authors.affiliation: University of Münster, MEET Battery Research Center, Institute of Physical Chemistry, Corrensstrasse 46, 48149, Münster, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Streipert
authors.affiliation: Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, Materials Synthesis and Processing (IEK-1), 52425, Jülich, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Uhlenbruck
authors.affiliation: University of Münster, MEET Battery Research Center, Institute of Physical Chemistry, Corrensstrasse 46, 48149, Münster, Germany.|Helmholtz Institute Münster, IEK-12, Forschungszentrum Jülich GmbH, Corrensstraße 46, 48149, Münster, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Winter
authors.affiliation: University of Münster, MEET Battery Research Center, Institute of Physical Chemistry, Corrensstrasse 46, 48149, Münster, Germany.
authors.forename: Tobias
authors.identifier: http://orcid.org/0000-0002-2097-5193
authors.initials: T
authors.lastname: Placke
keywords: aluminum current collectors; anodic dissolution; chromium nitride; lithium bis(trifluoromethanesulfonyl) imide (LiTFSI); protective coating