中文摘要：

以草酸亚铁、氢氧化锂和磷酸二氢铵为起始原料,活性炭为还原剂和碳源,采用微波水热法,合成LiFePO4微晶。研究反应温度对LiFePO4微晶结构和充放电性能的影响。利用X射线衍射仪、扫描电子显微镜和能谱色散谱仪表征合成产物的晶体结构、显微结构和元素组分,通过充放电测试对材料的电化学性能进行测试和分析。结果表明：在160～200℃,可合成单一物相的LiFePO4微晶;随着合成温度的升高,材料颗粒尺寸增大,由片状六方形长成准球形;170℃保温40min合成的材料粒径尺寸为1μm左右,其0.1C充放电比容量分别达到为156.1mAh/g和136.1mAh/g。

英文摘要：

Crystallites of LiFePO 4 were prepared by a microwave hydrothermal process using ferrous oxalate, ammonium dihydrogen phosphate, and lithium hydroxide as source materials, and acticarbon as reductive agent and carbon source. Influence of reaction temperature on structure and charge–discharge property of the LiFePO 4 crystallites was investigated. Crystalline structure, micro- structure, and elementary composition of the as-prepared crystallites were characterized by X-ray diffraction, scanning electron mi- croscopy, and energy dispersive spectrometry. A charge–discharge test was used for characterization of electrochemical properties of the powder. Results show that LiFePO 4 crystallites can be synthesized at 160–200 ℃. Grain size of the crystallites increases with the increase of reaction temperature and the corresponding morphology of LiFePO 4 crystallites is transformed from flaky hexagons to regular quasi-spheres. The grain size of the LiFePO 4 crystallite synthesized at 170 ℃ for 40 min is about 1 μm, and it has a charge capacity of 156.1 mA h/g and discharge capacity of 136.1 mA h/g at 0.1 C.