Investigations on Preparation and Electrochemical Performance Optimization of LiMnPO4/C Composites with High Tap Density

Abstract

AbstractIn this paper, the process route of synthesizing high tap density LiMnPO4 material by hydrothermal method with Li3PO4 as precursor is designed, and the microstructure and electrochemical properties of in situ carbon coated material are systematically studied. The phase, structure, morphology, and grain fineness distribution of the LiMnPO4/C are characterized by X‐ray diffraction, scanner transmission electron microscope, and laser particle size analyzer. There are a series of process parameters are optimized by orthogonal, such as reaction temperature, reaction time, polyethylene glycol 400 to H2O volume ratio and reactants concentration. The results show that, in the range of ≈2.5–4.5 V, the original charge–discharge volume of the prepared battery cathode material is shown as 123.7 mAh g−1 at a rate of 0.05 C. After 500 long cycles, the sample saves 95.55% (0.05 C) of the original capacity. At 550 °C, at different rates in the discontinuance voltage range of ≈2.5–4.5 V, the charge and discharge quantity of the cathode electrode raw materials obtained by individuals can be maintained at about 120.9 mAh g−1 (0.1 C), 119.0 mAh g−1 (0.5 C), 116.8 mAh g−1 (1 C), respectively.