title: XPS valence characterization of lithium salts as a tool to study electrode/electrolyte interfaces of Li-ion batteries.
abstract: X-ray photoelectron valence spectra of lithium salts LiBF4, LiPF6, LiTFSI, and LiBETI have been recorded and analyzed by means of density functional theory (DFT) calculations, with good agreement between experimental and calculated spectra. The results of this study are used to characterize electrode/electrolyte interfaces of graphite negative electrodes in Li-ion batteries using organic carbonate electrolytes containing LiTFSI or LiBETI salts. By a combined X-ray photoelectron spectroscopy (XPS) core peaks/valence analysis, we identify the main constituents of the interface. Differences in the surface layers' composition can be evidenced, depending on whether LiTFSI or LiBETI is used as the lithium salt.
authors.affiliation: LCTPCM, Université de Pau, Hélioparc Pau Pyrénées, 2 av. Pierre Angot, 64053 Pau Cedex 9, France. remi.dedryvere@univ-pau.fr
authors.forename: R
authors.initials: R
authors.lastname: Dedryvère
authors.forename: S
authors.initials: S
authors.lastname: Leroy
authors.forename: H
authors.initials: H
authors.lastname: Martinez
authors.forename: F
authors.initials: F
authors.lastname: Blanchard
authors.forename: D
authors.initials: D
authors.lastname: Lemordant
authors.forename: D
authors.initials: D
authors.lastname: Gonbeau