葡萄糖添加量对正极材料LiFePO_4电化学性能影响

Effects of glucose doped content on electrochemical performance of LiFePO_4 cathode materials

采用高温固相合成工艺,以葡萄糖为碳源对锂离子电池正极材料LiFePO4进行改性研究。通过X射线衍射(XRD)分析,扫描电子显微镜(SEM)及粉末比电阻对样品的晶体结构,微观形貌及电子电导率进行表征。结果表明加入葡萄糖未改变LiFePO4的晶体结构,葡萄糖的加入改善了材料的颗粒形貌,提高了材料的电子电导率。恒电流充放电结果表明:当碳包覆量为10%时LiFePO4的电化学性能最佳,0.1 C倍率下试样的首次放电比容量为155.57 mAh/g,倍率性较好。

Lithium-ion battery cathode materials LIFePO4 were synthesized by solid-state reaction modified by glucose as carbon source. The crystal structure, morphology and electronic conductivity of the samples were characterized through X-ray diffraction analysis, scanning electron microscopy and powder specific resistance. The results show that the modification by glucose does not change the crystal structure of LIFePO4. By adding carbon, the morphology of the material was improved and the electronic conductivity of the matedal was increased. The constant current charge-discharge results show that the electrochemical properties of LIFePO4 are best with 10% of the carbon content. The initial discharge specific capacity is 155.57 mAh/g at the 0.1 C rate with excellent rate capability.