Lithium-rich layered oxide nanoplate/carbon nanofiber composites exhibiting extremely large reversible lithium storage capacity

Novel 0.7Li2MnO3-0.3LiMO2 (LMO, M = Co, Ni, and Mn) nanoplates were successfully synthesized on a carbon nanofiber (CNF) matrix using our original ultracentrifugation material processing method (UC treatment). The 2D dimension-controlled LMO nanoplates with a length of 100 nm on a side and a thickness of 5-10 nm coexist with CNF in the as-prepared composite owing to the application of an ultrahigh centrifugal force of 75,000G in combination with the hydrothermal method. This first-reported LMO nanoplate/CNF (70/30 by weight) composite exhibited an extremely large reversible capacity at 0.1 C of 326 mA h g−1, which is close to its theoretical value (327 mA h g−1). This high capacity is due to the hyper dispersed and highly crystalline LMO nanoplates entangled within the CNF matrix. The prepared LMO nanoplates are covered with a thin unidentified layer (2-5 nm in thickness). The composite shows a high capacity of ca. 240 mA h g−1 at 1 C as well as stable cycle performance, maintaining 70% of its initial capacity over 100 cycles.