Lithium ion ) batteries (LIBs) play a vital role in various electronic devices in today's society, but the limited and uneven distribution of lithium resources makes them difficult to meet the needs of large-scale applications. For this reason, batteries based on earth-abundant alkali-metals, also known as "post LIBs", have been proposed as alternatives, and the discovery of anode materials suitable for various alkali-metal ion batteries (AMIBs) has become an important topic in scientific community. Carbonaceous electrode materials, including pure/doped/hybrid forms of carbon nanomaterials with sp 2 -hybridization such as fullerenes, graphene, and carbon nanotubes, are attracting significant attention as promising anode candidates for AMIBs. The recent report by Kothandam et al. reviewed latest overview of these advanced carbon-based structures in energy storage and conversion. Cyclocarbon is a new carbon allotrope, composed of carbon atoms holding hands.