Synthesis of graphene-supported LiFePO 4 /C materials via solid-state method using LiFePO 4 (OH) as precursors

The solid-state method is a mainly adopted large-scale preparation of LiFePO 4 cathode materials for Li-ion batteries but suffers from a challenge of irregular morphology and particle agglomeration. Herein, a graphene-supported LiFePO 4 /C@G composite with uniform morphology and electronic conducting network was synthesized via a freeze-drying assisted solid-state method without ball milling using the integrated LiFePO 4 (OH) as precursor. The integrated LiFePO 4 (OH) as precursor may avoid segregation of element caused by inhomogeneous mixing of raw materials in the process of solid-state preparation. The as-prepared graphene-coated LiFePO 4 /C@G shows excellent electrochemical properties with a specific capacity of 156, 154, 150, 145, 139, 132 mA h g −1 at 0.1, 0.2, 0.5, 1, 2, 5 C and a capacity retention of around 97.0% for 200 cycles at 2 C. This can be attributed to uniform element distribution and continuous electronic conducting network. The freeze-drying assisted solid-phase method using LiFePO 4 (OH) precursor and graphene is a promising route for production of LiFePO 4 /C materials with excellent performances.