Figure shows the segmentation of the XFC-cycled graphite anode at 9C charging after 450 cycles. For the 2D histogram, we masked out the glass capillary in the physical space. In addition, as with the pristine anode, we first assigned all negative graylevel values and those around zero to the background (Figure (C)). Next, we assigned the peak at the neutron graylevel value of ~ 2.2 a.u. and an X-ray graylevel value of ~ 0.3 a.u. to the cycled graphite since the database-derived linear X-ray attenuation coefficient of graphite is much lower than that of Cu (Figure ; Table ).