磷酸铁锂锂离子电池制备工艺的优化(英文)

Technology Optimization of Preparing Lithium Ion Battery of LiFePO_4

采用固相法合成磷酸铁锂锂离子电池正极材料。X射线衍射分析(XRD)显示合成的样品具有橄榄石晶型结构。扫描电镜(SEM)结果显示LiFePO4的大小在0.5～2.5μm,并且形状不规则。通过电化学测试研究了不同物料配比和涂膜厚度对LiFePO4电化学性能的影响。结果显示:当物料配比为85:10:5、涂膜厚度为200μm时,以LiFePO4为正极的电池在0.1C下首次放电比容量为134.8mAh/g。从循环伏安测试(CV)发现,优化后的样品对于Li+的脱出与嵌入具有很好的可逆性,这一性能同样被交流阻抗分析(AC)所证实。

Lithium iron phosphate (LiFePO4) powders were synthesized by a solid state method. X-ray diffraction (XRD) patterns reveal an orthorhombic olivine-type structure. The scanning electron microscopy (SEM) result indicates that LiFePO4 particles possess the size 0.5-2.5 μm and an irregular shape. Electrochemical test indicates the performance of LiFePO4 cathode material with different mixture ratio in different spread thickness. The cathode material with the mixture ratio of 85:10:5 in 200 μm has the discharge capacity of 134.8 mAh/g at the current of 0.1 C. From the result of cyclic voltammetry, it is found that the optimized sample has good reversibility for lithium extraction/ insertion reactions, which is further proven by impedance analysis.