fig7
Figure 7. (A) Device layout and working principle. (B) The propagating front (dashed white line) of Li crystal forming inside bilayer graphene during lithiation. Time-resolved TEM images show microstructure evolution of the BP sheet during the first cycle: (C) pristine BP sheet. (D and E) discharging process. The anode cracking and pulverization accompanying the huge size increase appeared in the delithiation process, greatly different from the commonly accepted understanding. (F) Typical magnified TEM image of the delithiated anode, showing obvious cracking. (A and B) are adapted with permission from Ref.[84], copyright 2018, Springer Nature; (C-F) are adapted with permission from Ref.[85], copyright 2016, American Chemical Society.







