Lithium analysis in Li-ion battery materials via a scanning electron microscopy-based approach

We performed Li analysis by reflection electron energy loss spectroscopy (REELS) with a scanning electron microscopy-based apparatus. It was possible to distinguish between Li compounds containing different transition metal elements spatially, via the spectrum imaging scheme of REELS spectra. We also acquired the Li spectrum for an Li-inserted graphite negative electrode. REELS measurements with hemispherical analyzer were performed to obtain high-quality spectra with sufficient energy resolution and compared with those from cylindrical mirror analyzer measurements; the former provided a more detailed chemical state evaluation of Li.