Abstract
The phase transition caused by electrochemical intercalation of lithium into graphite electrodes has been investigated in 1M LiClO4/propylene carbonate (PC) and PC+ ethylene carbonate solutions by using a newly designed electrochemical cell which allows electrochemical in situ X-ray diffraction (XRD) measurements. Our cell had a thin film of polypropylene as an X-ray window, and working (carbon sheet) electrodes were hot-pressed to the window. The well distinguished C (100) and C (101) peaks present at a high 2θ region as well as the C (002) peak were measured as a function of electrode potential, and it was suggested that the stacking transition takes place at a narrow potential range around 0.2V vs. Li, which corresponds to a transition region from the second stage to a higher stage.
