Li sub(4)Ti sub(5)O sub(12)/graphene nanoribbons composite as anodes for lithium ion batteries

In this paper, we report the synthesis of a Li sub(4)Ti sub(5)O sub(12)/Graphene Nanoribbons (LTO/GNRs) composite using a solid-coating method. Electron microscope images of the LTO/GNRs composite have shown that LTO particles were wrapped around graphene nanoribbons. The introduction of GNRs was observed to have significantly improved the rate performance of LTO/GNTs. The specific capacities determined of the obtained composite at rates of 0.2, 0.5, 1, 2, and 5 C are 206.5, 200.9, 188, 178.1 and 142.3 mAh.g super(-1), respectively. This is significantly higher than those of pure LTO (169.1, 160, 150, 106 and 71.1 mAh.g super(-1), respectively) especially at high rate (2 and 5 C). The LTO/GNRs also shows better cycling stability at high rates. Enhanced conductivity of LTO/GNRs contributed from the GNR frameworks accelerated the kinetics of lithium intercalation/deintercalation in LIBs that also leads to excellent rate capacity of LTO/GNRs. This is attributed to its lower charge-transfer resistance (Rct = 23.38 Omega ) compared with LTO (108.05 Omega ), and higher exchange current density (j = 1.1 10 super(-3) mA cm super(-2))-about 20 times than those of the LTO (j = 2.38 10 super(-4) mA cm super(-2)).