Preparation and Characterization of LiFePO₄/Graphene Composite Cathode Materials by High Temperature Reduction GO

Abstract

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.

Keywords

• graphene oxide(GO)
• graphene
• spray drying
• conductive network
• electrochemical performance