摘要
以明胶作为增稠剂,葡萄糖为碳源,用明胶-凝胶法结合真空冷冻干燥技术制备LiFePO4/C复合材料。利用X射线衍射、扫描电镜分别测定材料的晶体结构、形貌。以恒电流充放电、电化学阻抗谱测试材料的电化学性能。结果表明:前驱体具有稳定的网状结构,合成出的产物LiFePO4/C复合材料具有橄榄石型结构,其中650℃烧结出的样品的颗粒直径为400～600nm,0.1C倍率放电容量达到161mA h/g,不同倍率下循环20次容量均无明显衰减。
The LiFePO4/C composites were prepared by a freeze drying method using gelatin as a thickener, glucose as a carbon source. The structure, morphology and electrochemical performance were characterized by X-ray diffraction, scanning electron mi- croscopy, electrochemical impedance spectroscopy and galvanostatic charge-discharge test, respectively. The results show that the precursor has a stable network structure, and the products have an olivine crystal structure. The crystal size of LiFePO4/C composite synthesized at 650 ~C was 400-600 nm, and the discharge capacity was 161 mA.h/g at 0.1 C rate. There was little attenuation for 20 cycles at different volume ratios.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2012年第2期261-265,共5页
Journal of The Chinese Ceramic Society
基金
安徽省教育厅(KJ2010A278)资助项目
关键词
明胶
磷酸铁锂
真空冷冻干燥
网状结构
gelatin
lithium iron phosphate
freeze drying method
network structure
