LiFePO_4高温固相合成工艺优化研究

Optimization of high-temperature solid-phase process for LiFePO_4 synthesis

采用正交试验法优化LiFePO4固相反应合成工艺,研究预烧温度、合成温度、保温时间等对锂离子电池正极材料LiFePO4电化学性能的影响。结果表明,预烧温度350℃、合成温度650℃、保温时间12 h为最佳合成工艺条件。按最佳合成工艺所制样品的首次放电比容量达151.7 mA.h/g,循环充放电30周后,其放电比容量仍为140.9 mA.h/g。

The process of LiFePO4 synthesis through the solid-phase reaction method is optimized by orthogonal tests. The three main factors influencing the electrochemical properties of the material （preheat temperature, synthesis temperature and holding time） are investigated. In the optimized synthesis process, the preheat temperature is 350℃, the synthesis temperature is 650℃, and the holding time are 12 hours. The first discharge capacity of the optimized sample is 151.7 mA·h/g, and it remains to be 140.9 mA·h/g after cycling for 30 cycles.