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A facile and practical route was introduced to prepare LiFePO4/C cathode material with nano-sized primary particles and excellent electrochemical performance. LiH2PO4 was synthesized by using H3PO4 and LiOH as raw materials. Then, as-prepared LiH2PO4, reduced iron powder and α-D-glucose were ball-milled, dried and sintered to prepare LiFePO4/C. X-ray diffractometry was used to characterize LiH2PO4, ball-milled product and LiFePO4/C. Differential scanning calorimeter-thermo gravimetric analysis was applied to investigate possible reactions in sintering and find suitable temperature for LiFePO4 formation. Scanning electron microscopy was employed for the morphology of LiFePO4/C. As-prepared LiH2PO4 is characterized to be in P21cn(33) space group,which reacts with reduced iron powder to form Li3PO4, Fe3(PO4)2 and H2 in ball-milling and sintering. The appropriate temperature for LiFePO4/C synthesis is 541.3-976.7 °C. LiFePO4/C prepared at 700 °C presents nano-sized primary particles forming aggregates. Charge-discharge examination indicates that as-prepared LiFePO4/C displays appreciable discharge capacities of 145 and 131 mA·h·g-1at 0.1 and 1 C respectively and excellent discharge capacity retention.
LiH2PO4 was synthesized by using H3PO4 and LiOH as raw materials. Then, as-prepared LiH2PO4, reduced iron powder and α- D-glucose were ball-milled, dried and sintered to prepare LiFePO4 / C. X-ray diffractometry was used to characterize LiH2PO4, ball-milled product and LiFePO4 / C. Differential scanning calorimeter-thermo gravimetric analysis was applied to investigate possible reactions in sintering and find suitable temperature for LiFePO4 formation. Scanning electron microscopy was employed for the morphology of LiFePO4 / C. As-prepared LiH2PO4 is characterized to be in P21cn (33) space group, which reacts with reduced iron powder to form Li3PO4, Fe3 ( PO4) 2 and H2 in ball-milling and sintering. The appropriate temperature for LiFePO4 / C synthesis is 541.3-976.7 ° C. LiFePO4 / C prepared at 700 ° C presents nano-sized primary particles for ming aggregates. Charge-discharge examination indicates that as-prepared LiFePO4 / C displays appreciable discharge capacities of 145 and 131 mA · h · g-1 at 0.1 and 1 C respectively and excellent discharge capacity retention.