"Water-in-salt" solutions (hydrate melts) are a class of ionic liquids and as such promising electrolytes for future aqueous Lithium-ion batteries, distinguishing themselves through safe use, reliability, and environmental friendliness. In the scope of this work, which was carried out at the Super Photon Ring - 8 GeV (SPring-8) in Japan, the structure of a Lithium salt hydrate melt (LSHM) was investigated at the beamline BL07LSU for soft X-ray spectroscopy. To relate the absorption and emission spectra thus obtained und the structure of the LSHM, Molecular Dynamics (MD) simulations were carried out in addition to the experiment. Based on that, elementary structures were identified in the simulation and with the help of a DFT software, the theoretical emission spectra of those structures were calculated. The comparison between the experimental and theoretical spectra gives an impression of the bonding between Lithium, water, and the other molecules present in the hydrate melt, and may explain the transport of Lithium in LSHM. Furthermore, to improve the experimental capabilities of the spectrometer at BL07LSU, ray-tracing calculations for mirrors and other optics of the spectrometer were performed. By making use of these new optics, an improvement of a factor of 3 to 4 in spectrometer resolution is expected. Future experiments, among them experiments on LSHM, will benefit from this development.