Surfactant-Assisted Synthesis of Micro/Nano-Structured LiFePO₄ Electrode Materials with Improved Electrochemical...

As an electrode material, LiFePO₄ has been extensively studied in the field of energy conversion and storage due to its inexpensive cost and excellent safety, as well as good cycling stability. However, it remains a challenge to obtain LiFePO₄ electrode materials with acceptable discharge capacity at low temperature. Here, micro/nano-structured LiFePO₄ electrode materials with grape-like morphology were fabricated via a facile solvothermal approach using ethanol and OA as the co-solvent, the surfactant as well as the carbon source. The structure and electrochemical properties of the LiFePO₄ material were investigated with x-ray diffraction (XRD), field emission scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and the formation mechanism of the self-assembled micro/nano-structured LiFePO₄ was discussed as well. The micro/nano-structured LiFePO₄ electrode materials exhibited a high discharge capacity (142 mAh·g^-1) at a low temperature of 0 °C, and retained 102 mAh·g^-1 when the temperature was decreased to -20 °C. This investigation can provide a reference for the design of micro/nano-structured electrode materials with improvement of the electrochemical performance at low temperature.