锂离子电池用LiFePO4的合成及性能研究

利用尿素与无机盐组成低温熔盐体系，在该体系下合成LiFePO4材料的前驱体。研究了后续煅烧温度对材料性能的影响。研究结果表明，在650℃烧结8h合成的正极材料LiFePO4具有较好的放电性能，做成的扣式电池1C电流放电容量达到75mAh／g；该材料具有与商品化材料相同的晶体结构和较小的晶胞体积和晶轴尺寸。

Preparation and performance of LiFePO4 material for Li-ion battery

The precursor materials to lithium iron phosphate were synthesized under the low temperature molten salts system, in which urea and inorganic salts composition were contained. The effect of followup calcination temperature on performance of the material was discussed in this paper. It showed that the lithium iron phosphate material which was calcined at 650~Clot 8h had better discharge performance. This kind of material was tested in button cells. At room temperature and 1C discharge rate, the discharge capacity achieved 75mAh/g. Compared with commercialization materials, LiFePO4 synthesized in this paper exhibited ahnost the same crystal structure, smaller unit cell volume and crystal axis size.