乙二醇辅助固相法合成LiFePO4
Ethylene Glycol-Assisted Synthesis of LiFePO4 by Traditional Solid-State Method

作者: 李艳 , 刘英才 * , 王洁 :中国海洋大学材料科学与工程研究院,青岛;

关键词: 锂离子电池LiFePO4正极材料固相合成法乙二醇Lithium-Ion Battery Lithium Iron Phosphate Cathode Material Solid-State Method Ethylene Glycol

摘要:
本文以Li2CO3FeC2O4·2H2ONH4H2PO4为原料,采用传统的固相法合成锂离子电池正极材料LiFePO4/C,为了提高电化学性能,加入乙二醇进行表面改性。利用X射线衍射仪(XRD),扫描电子显微镜(SEM)对材料晶体结构、表观形貌和化学成分进行表征,采用恒电流充放电测试技术对其电化学性能进行测定,并且研究了乙二醇对LiFePO4/C晶体生长方向的影响。结果表明经乙二醇改性的LiFePO4/C颗粒呈板状堆积,在0.1 C0.5 C1.0 C的电流密度下充放电平台稳定,并且具有较好的循环效率。

Abstract:
Lithium-ion battery cathode material LiFePO4/C was synthesized by Li2CO3, FeC2O4·2H2O, NH4H2PO4 ina traditional way, and ethylene glycol was used as surfactant for advancing electrochemical performance. The crystalline structure, morphology and chemical composition of LiFePO4/C particles were characterized by X-ray diffraction, scan- ning electron microscopy and electrochemical performance was characterized by constant-current charge-discharge test technique, respectively. In addition, the effects of ethylene glycol on the crystal growth direction were discussed in this paper. The results show that the grains of LiFePO4/C which are synthesized with ethylene glycol-assisted present plate- type accumulation. The charge-discharge potential flats present smooth in different current density (0.1C,0.5Cand1.0C) and the cycle abilityis stable.

文章引用: 李艳 , 刘英才 , 王洁 (2013) 乙二醇辅助固相法合成LiFePO4。 材料科学, 3, 230-235. doi: 10.12677/MS.2013.35041

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