Electrochemical Rubidium Storage Behavior of Graphite in Ionic Liquid Electrolyte

Electrochemical intercalation behaviors of alkali metals into graphite have been vigorously studied in academic and industrial fields, whereas their mechanisms are still unclarified. In this study, we report a novel rubidium-ion battery utilizing an ionic liquid electrolyte and natural graphite as the negative electrode material operating at room temperature. The electrochemical phase evolution behavior of rubidium–graphite intercalation compounds was elucidated using X-ray diffraction. The graphite negative electrode exhibited an initial discharge capacity of 216 mAh g−1 at 0.05 C rate, and retained its capacities of around 180 mAh g−1 even at 0.5 C rate for 50 cycles