Improvement of Ultra Soft X-ray Absorption Spectroscopy and Photoelectron Spectroscopy Beamline for Studies on Related Materials and Cathodes of Lithium Ion Batteries

For analysis of lithium ion batteries, the soft X-ray grating monochromator beamline BL-2 at SR center of Ritsumeikan University has been upgraded: adding a new grating (900 l/mm) to extend the available energy up to 1000 eV, and constructing a XAFS (X-ray Absorption Fine Structure)-PES (photoelectron spectroscopy) chamber equipped with in-situ transfer vessel systems. With this beamline, Li K-, O K- and 3d transition metal (TM) L- XAFS and Li 1 s PES spectra were measured for several compounds related to Li ion batteries. For precise analysis of the Li chemical state, some of Li compounds, as well as Li metal were prepared by vacuum deposition.