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Anionic polymer cathode material LiFePO 4 because of its low cost, environmentally friendly, high specific capacity, good cycle performance, security, good range of benefits, is considered the most promising next-generation lithium-ion battery cathode material. Currently, poly anionic Li 2 FeSiO 4 is also being developed as a new class of lithium-ion battery cathode material, Li 2 FeSiO 4 have the LiFePO 4 similar to the crystal structure, chemical and thermal stability. In addition, since the raw material is more abundant, cheaper, less environmental pollution, Li 2 FeSiO 4 as a cathode material than LiFePO 4 more appeal. In this paper, the sol - gel method, solid-phase method were prepared LiFePO 4 / C and Li 2 FeSiO 4 / C cathode material, the use of XRD, SEM, constant current charge and discharge, EIS, CV studied the calcination temperature and calcination time, carbon, the carbon content of the material morphology and electrochemical properties. Glycine as a complexing agent for the first time by sol - gel method LiFePO 4 / C cathode materials investigated calcination temperature and calcination time, carbon, carbon content on the morphology and electrochemical properties effects. The results show that the particle size with the calcination temperature and the heat treatment time increases, but decreases with the increase of carbon content. Sucrose as a carbon source (10 wt%), 12 h at 700oC calcined material prepared with the best electrochemical performance to 0.1 C-rate discharge, the discharge specific capacity of 162 mAh g -1 , after 20 cycles, the capacity retention ratio was 158 mAh g -1 . Using an improved solid phase prepared LiFePO 4 / C, investigated the calcination temperature, calcination time, carbon, the carbon content of the material morphology and electrochemical properties. The results showed that sucrose as a carbon source (10 wt%), 14 h at 750oC calcined material prepared with the best electrochemical performance, respectively 0.1,0.2,0.5,1,2,5 C-rate discharge, the discharge capacity respectively 155,145,139,132,120,85 mAh g -1 . Sol - gel method Li 2 FeSiO 4 / C cathode materials investigated calcination temperature and calcination time, the carbon content on the physical properties of materials and electrochemical performance effects. The results showed that 12 h at 650oC calcination prepared Li 2 FeSiO 4 / C material has the best electrochemical performance to 1/16 C-rate discharge, first discharge capacity of 150 mAh g -1 , after 20 cycles, the discharge capacity retention was 97%.
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