Analysis of Intercalation/De-Intercalation of Li Ions Into/From Graphite at 0 °C via Operando Synchrotron X-ray Diffraction

The charge/discharge reaction mechanisms of graphite negative electrodes in Li ion batteries were investigated via operando synchrotron X-ray diffraction at 0 °C and 25 °C. intercalation ions formed the stage 1 compound with an in-plane structure LiC 6 ; while only 2, structures 9 . degree expansion a, b -axes c -axis directions by was less than that Hence, it difficult to form further increases concentration, charging low temperature became difficult. De-intercalation did not follow Daumas–Hérold model proceeded discretely order: → 2 4 graphite, without going through stages 3, 5–8 dilute 1.