摘要
以钛酸四丁酯为掺杂剂,抗坏血酸为碳源,采用溶胶-凝胶法合成Ti^(4+)掺杂的锂离子电池正极材料Li_2FeSiO_4。通过X线衍射(XRD)、场发射扫描电子显微镜(FESEM)、高频红外碳-硫分析仪、循环伏安及恒电流充放电测试等表征手段分析了Ti元素掺杂对Li_2FeSiO_4结构、形貌、放电容量、循环稳定性的影响。结果表明:掺Ti减小了Li_2FeSiO_4颗粒尺寸,增加了其与电解液间的接触面积,提高了锂离子的迁移率,从而提高了放电容量。在10 mA/g电流密度下,Ti掺杂的试样首次充放电容量分别为206.9 mA·h/g和172 mA·h/g;未掺杂的试样的充放电电容量分别为169.1 mA·h/g和143.7 mA·h/g。
Ti-doped cathode material Li_2FeSiO_4 for Li-ion battery was synthesized by a sol-gel method using ingtetrabutyl titanate as a dopant and ascorbic acid as carbon source. The effects of Ti doping on structure,morphology,discharge capacity,and cycling stability were characterized by X-ray diffraction（ XRD）,field emission scanning electron microscope（ FESEM）,cyclic voltammogram,and galvanostatic charge-discharge measurement. Results showed that Ti doping decreased particle size,increased the contact area between particles and electrolyte and enhanced lithium ion mobility,thus improving the discharge capacity of Li_2FeSiO_4. At the current density of 10 mA / g,the initial charge and discharge capacities for the doped sample were 206. 9 mA · h / g and 172 mA · h / g,while the undoped samples were 169. 1 mA·h / g and 143. 7 mA·h / g,respectively.
出处
《南京工业大学学报（自然科学版）》
CAS
北大核心
2016年第2期64-69,共6页
Journal of Nanjing Tech University(Natural Science Edition)
基金
教育部高等学校博士点基金(20133221110009)
国家自然科学基金(51404142)
江苏高校优势学科建设工程
