以锂∶铁∶磷摩尔比为1∶1∶1为原料,采用溶剂热法合成了纯的、晶型规则的亚微米级LiFe-PO4;再加入酚醛树脂经高温处理合成了LiFePO4/C复合正极材料,其振实密度高,加工性能好。利用X射线衍射（XRD）、扫描电子显微镜（SEM）及恒电流充放电技术研究了溶剂热温度、时间对产物组织结构及性能的影响。结果表明溶剂热温度为190℃、溶剂热时间为24h合成样品表现出良好的电化学综合性能,振实密度为1.25g/cm3;室温下0.1C倍率充放电,放电比容量达到151.3mAh/g;在1C倍率下放电时,材料放电比容量仍能保持在120.1mAh/g左右。
The pure,well-developed prism shapes and well-crystallized LiFePO4 was synthesized by solvothermal process using n（Li1＋）∶n（Fe2＋）∶n（PO43＋）=1∶1∶1 as starting material.Adding the phenolic resin,LiFePO4/C was obtained during the high temperature process,which had high tap density and good machinability.The effects of solvothermal process temperature and process time on microstructure and electrochemical properties of LiFePO4 and LiFePO4/C were investigated by the methods of X-ray diffraction（XRD）,scanning electron microscope（SEM）,and constant current charge-discharge.The results showed that the sample prepared at 190℃/24h performs good properties,whose tap density was 1.25g/cm3 and discharge specific capacity was 151.3mAh/g at 0.1C and 120mAh/g at 1C under room temperature.
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