Enhancement of Lithium Storage Performance of Carbon Microflowers by Achieving a High Surface Area

High‐surface‐area, nitrogen‐doped carbon microflowers (A‐NCFs‐4) assembled from porous nanosheets are prepared in a three‐step process: soft‐templating self‐assembly, thermal decomposition, and KOH activation. The hydrazine hydrate used in our experiment serves not only as a structure‐directing agent, but also as a nitrogen source. The resultant A‐NCFs‐4 has a hierarchical porous structure and its specific surface area is as high as 2309 m² g^?1. When used as anode, it exhibits a reversible capacity as high as 807 mAh g^?1 at 300 mA g^?1 after 100 cycles, and an excellent rate capability of 200 mAh g^?1 at a high current density of 8 A g^?1. Compared with unactivated counterpart, A‐NCFs‐4 exhibits a significantly improved lithium storage capacity and rate capability; this can be attributed to its unique structural characteristics and high surface area. The hierarchical micro‐/mesopore structure, high surface area, and nitrogen doping of A‐NCFs‐4 could guarantee fast mass transport for lithium species, enhance the A‐NCFs‐4/electrolyte contact area, shorten the lithium‐ion diffusion length, and accommodate strain induced by volume changes during the electrochemical reaction. The results indicate that the as‐prepared A‐NCFs‐4 could be a promising candidate as a high‐performance anode for lithium‐ion batteries.