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Micro layer of GO was obtained by micro adjustment and control. LiFePO4/graphene composite cathode materials were synthesized using a spray drying followed by high temperature reduction modification method, to improve conductivity of LiFePO4 with excellent conductivity of graphene. The structure, morphology and electrochemical performance of the composite materials were characterized by XRD, FTIR, SEM, TEM and electrochemical measurement technologies. The three-dimensional conductive network was constructed by graphene composite in material particles, which can improve the charge transfer rate of the interface of electrolyte/electrode materials and the electrochemical performance of LiFePO4. The results show that the discharge specific capacity of LiFePO4 without graphene is only 155mAh/g, while the discharge specific capacity of LiFePO4/graphene is 164mAh/g at 0.1C.The discharge specific capacity of LiFePO4/graphene is 140,119mAh/g at 1,2C,respectively.

The CNTs/rGO/NG composite lithiumion battery anode material was synthesized by thermal reducing, using graphene oxide (GO) and carbon nanotubes (CNTs) as precursors for a 5 ∶ 3 proportion. The morphology, structure, and electrochemical performance of the composite were characterized by scanning electron microscopy(SEM), X-ray diffractometry(XRD), Fourier transform infrared spectra (FTIR) and electrochemical measurements. The results show that reduced graphene oxide and carbon nanotubes form a perfect three-dimensional network structure on the surface of natural graphite. CNTs/rGO/NG composite has good rate performance and cycle life,compared with pure natural graphite.The initial discharge capacity of designed anode is 479mAh/g at 0.1C, the reversible capacity up to 473mAh/g after 100 cycles,the capacity is still 439.5mAh/g, the capacity retention rate is 92%,and the capacity is 457, 433, 394mAh/g at 0.5, 1, 5C, respectively.