We show a continuous, in situ nuclear magnetic resonance (NMR) experiment on a lithium/graphite electrochemical cell. The objective is to study a commercial graphite currently used as negative electrodes in secondary lithium batteries. A plastic cell is made, with metallic lithium as the counter electrode and 1 mol dm −3 LiPF 6 /ethylene carbonate (EC) + diethylcarbonate (DEC) electrolyte. The reversible capacity is 346 mAh/g and the irreversible capacity 55 mAh/g, measured in the galvanostatic mode, at a rate of C /20 (20 h for the theoretical capacity of LiC 6 ) for the first cycle. We show the first discharge and the first charge of the cell inside the magnet and record simultaneously and regularly (in real time) static 7 Li NMR spectra. As expected, we observe the quadrupolar lines characteristic of the lithium graphite intercalation compounds (GICs). During the discharge, the two types of in-plane densities of Li are successively found that correspond to the dilute LiC 9 , then to the dense LiC 6 configuration; during the charge, we observe the successive decrease of these states. The galvanostatic curve helps to identify the stages NMR signature and the stages coexistence.
