摘要
以LiOH·H2O(、NH4)2HPO4、FeSO4·7H2O为原料,通过沉淀法制备锂离子电池正极材料LiFePO4前驱体,前躯体中混入2wt%的活性炭在550℃烧结6h得到橄榄石型的LiFePO4。研究了反应时间、烧结温度、烧结时间对合成LiFePO4的影响,利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、热重-差热综合分析(TG-DTA)、红外光谱(FTIR)等手段对合成的LiFePO4的结构、形态、热化学性质和电化学性能进行了研究,结果表明化学沉淀法制备橄榄石型LiFePO4正极材料呈形貌规整的类球形颗粒,晶型发育完善,粒度分布均匀。LiFePO4样品在室温首次放电容量119.5mAh·g-1,8次循环后放电容量衰减低于2%。
The mixed precursor that includes ferrous phosphate and lithium phosphate is synthesized by chemical precipitation method, using LiOH, （NH4）2 HPO4 FeSO4 · 7H2O as raw materials. The precursor powder was mixed with 2wt. % activate carbon and sintered 6 hours at 550℃ to prepare olivine LiFePO4. The samples were characterized by XRD, SEM, TG-DTA and FTIR spectra. The LiFePO, shows perfect olivine structure. The grain of the LiFePO4 sample is nearspherical shape and grain size distribution is uniform. At the 0.1C rate, the initial specific discharge capacity of LiFePO4 at room temperature reached 119.5mAh/g, with lower than 2% capacity fading after 8 cycles.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2008年第3期385-389,421,共6页
Journal of Materials Science and Engineering
基金
国家自然科学基金资助项目(50474092)
深圳市科技计划资助项目(200505)
