采用水热模板法合成纳米级LiFePO4材料,改变水热反应中表面活性剂(十六烷基三甲基溴化铵)的比例控制样品颗粒生成的大小.SEM测试表明,合成的LiFePO4晶粒尺寸与表面活性剂的配比密切相关,范围在几十到几百nm之间.充放电试验表明,合成的纳米级LiFePO4材料电极具有优良的电化学性能,其0.1C放电最高比容量可达150 mAh/g,而1C和2C放电比容量也分别有140 mAh/g和126 mAh/g.
The cathode materials of nanosiged LiFePO4 were prepared by hydrothermal templating synthesis.The grain sizes and electrochemical performance of LiFePO4 were controlled by surfactant.It was shown that the grain sizes varied from less than a hundred to hundreds nanometers by the SEM images.In the charge/discharge tests,the discharge capacities of the sample as a lithium ion battery were achieved to 150 mAh/g at 0.1C,140 mAh/g at 1C,and 126 mAh/g at 2C,with good cycling performance.
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