The effect of chemical etching on the electrochemical intercalation of lithium into multi-walled carbon nanotubes (MWNTs) was investigated. The results showed that the charge capacity of etched MWNTs is greater than the theoretical capacity of graphite. Moreover, the charge curve does not show a well-defined voltage plateau. To explain this phenomenon, we proposed a non-GIC (graphite intercalation compound) mechanism that, except for the lithium intercalated between graphene layers to form graphite intercalation compounds, the higher charge capacity should be related to lithium doped into such regions as disordered graphitic structures, defects, microcavities, and edges of graphitic layers, which is generally called a non-GIC mechanism in this paper.