Enhanced Li-ion battery performance of TiO2 nanoparticle-loaded Li4Ti5O12 nanosheet anode using carbon coated copper as current collector

A novel rutile TiO2 nanoparticle-loaded Li4Ti5O12 nanosheet ([email protected]) composite nanomaterial is successfully synthesized. It consists of TiO2 nanoparticles with an average diameter of 7 nm and Li4Ti5O12 nanosheets of 5 nm in average thickness, and the TiO2 nanoparticles are uniformly loaded on the surface or between the layers of laminated Li4Ti5O12 nanosheets, by which the good dispersion of nanosheets can be obtained due to the separation function of nanoparticles between nanosheets. The unique nanostructure facilitates to improve the electron and Li ion conductivities of Li4Ti5O12 anode. Additionally, a graphene & graphite (Gn&Gi) coating is applied between the active materials and copper foil to improve the electron transportation capacity. The fabricated Gn&[email protected] coated copper foil electrode demonstrates much enhanced rate and recycling performance, it maintains a voltage platform at 1.5 V, and delivers a discharge specific capacity of 167.73 mAhg−1 at 10 C with a capacity retention rate of 80.1% after 2000 cycles. At 50 C, the specific discharge capacity can also reach 135.05 mAhg−1, and after 1000 cycles, the capacity retention rate is 88.8%. The results indicate that the graphene & graphite coating can significantly reduce the resistance between active materials and copper current collector.