Tunable Morphology Synthesis of Lithium Iron Phosphate as Cathode Materials for Lithium-Ion Batteries

Tailor-designed structure is an essential method to improve energy density capacity retention and energy density of lithium-ion batteries. Herein, we designed and synthesized lithium iron phosphate (LiFePO4) with ellipsoidal, hierarchical, and nanosheets morphologies by a solvothermal using phytic acid as phosphorus source. The influence of mole ratio on the morphologies and electrochemical performances were studied. The results illustrated that phytic acid dosage plays a vital role in the tunable morphology syntheses process. Additional, electrochemical measurement confirms that hierarchical LiFePO4 exhibits higher initial discharge capacity (162.09 mAh g−1, 0.1C), more excellent high-rate discharge capability (114.13 mAh g−1, 10C), and better cycle stability (97.2% at 1C after 150 cycles). This satisfactory electrochemical performance could be ascribed to the moderate size and fast ion transport kinetics, which caused by the changing of thermodynamics and kinetics in synthesis process.