| Olivine structured LiFePO4 is one of the promising cathode materials for lithium ion batteries due to its large theoretical capacity of 170mAh/g combined with a discharge voltage 3.4V vs. Li+/Li. There is nearly no influence on the crystal structure during delithiation-lithiation. Furthermore, it is inexpensive, environmentally benign, and has excellent thermal stability during charge-discharge and the raw materials are abundant.Among many preparation methods for lithium iron(II) phosphate, the iron(II) oxalate as a iron source is a conventional preparation method. When ferrous compounds, especially iron(II) oxalate were raw materials, ferrous compounds tended to be oxidized without inert atmosphere during grinding the precursor. The N2 or Ar protective gas made the preparation equipment and the technology complication. Besides, the cost of iron(II) oxalate is relatively high. In the paper, LiFePO4 powder have been tried to synthesize by a two-step sintered solid state reaction using ferric compound as raw materials under H2 as both reducing and protective atmosphere with a view to simplify the synthesis technology and cut down the cost. In the paper, it has been considered that the raw materials type affected on the performance of the products, and its performance has been compared to that from iron (II) oxalate. The main conclusions are as follows:1. The olivine structured lithium iron(II) phosphate could been synthesized by a solid state reaction with a two-step calcination using ferric compound and H2 as iron source and a reducing and protective gas, respectively. It has been showed by XRD spectra, thermaogravimetric analysis(TG), cyclic voltammetry(CV) tests and charge- discharge tests that lithium iron(II) phosphate from the ferric compound was close to these from the FeC2O4 and the Fe3(PO4)2 on crystal structure, pure of the phase and electrochemical performance. The low intrinsic conductivity was a common problem, which made the electrochemical...
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