Preparation of porous structure LiFePO4/C composite by template method for lithium-ion batteries

Cationic surfactant cetyltrimethylammonium bromide (CTAB) was used as template to prepare porous structure LiFePO4/C composite by the template method. The porous structure LiFePO4/C composites were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), transition electron microscopy (TEM), high voltage electron microscopy (HVEM), and nitrogen adsorption–desorption test. The structures and electrochemical performances of the samples calcined at different calcination times at 700 °C were studied. The results indicate that the porous structure LiFePO4/C composite prepared at 700 °C for 24 h exhibited the best electrochemical performance, the discharge capacity is up to 152.1 mAh g− 1 at 0.1 C rate. Compared with nano-sized LiFePO4/C composite without template, porous structure LiFePO4/C could dramatically improve the rate capability because of its higher specific surface area and more channels for fast lithium ion diffusion.

► The porous structure LiFePO4/C composite was prepared by template method. ► The cathode showed excellent electrochemical reversibility and structural stability. ► Carbon coated on porous LiFePO4/C material increased its electronic conductivity. ► A proposed model explained the possible reasons for the capacity degradation.