“…[172][173][174][175][176] In situ optical microscopy (IOM) methods have been used to investigate Li deposition on Li metal anodes 143,144,177 and other anode materials. 68,72,142,[178][179][180] By choosing a cross-sectioned full cell optical setup, a near realistic cell configuration was reached by Hogrefe et al 68,178,181 Due to the cross-sectional view, lithiation gradients through the anode coating can be observed by the different colours of Li-graphite intercalation compounds (Li-GICs: LiC 18 : blue, 180,182,183 LiC 12 : red, 180,182,183 and LiC 6 : yellow/golden 180,182 ). 68,178 Additionally, the nucleation of Li depositions, growths of Li dendrites, and internal short circuits by these dendrites can be directly observed, which become evident by the appearance of shiny-silver, dendritic, and moss-like structures on the anode.…”