物理化学学报 >> 2014, Vol. 30 >> Issue (9): 1641-1649.doi: 10.3866/PKU.WHXB201406172

电化学和新能源 上一篇    下一篇

锂离子电池正极材料Li1.2Mn0.54-xNi0.13Co0.13ZrxO2的制备及电化学性能

任祥忠, 刘涛, 孙灵娜, 张培新   

  1. 深圳大学化学与化工学院, 广东深圳 518060
  • 收稿日期:2014-04-18 修回日期:2014-06-16 发布日期:2014-08-29
  • 通讯作者: 任祥忠 E-mail:renxz@szu.edu.cn
  • 基金资助:

    国家自然科学基金(21000174)及深圳市战略新兴产业发展基金(JCYJ20120613163733279,JCYJ20130329113849606)资助项目

Preparation and Electrochemical Performances of Li1.2Mn0.54-xNi0.13Co0.13ZrxO2 Cathode Materials for Lithium-Ion Batteries

REN Xiang-Zhong, LIU Tao, SUN Ling-Na, ZHANG Pei-Xin   

  1. College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060, Guangdong Province, P. R. China
  • Received:2014-04-18 Revised:2014-06-16 Published:2014-08-29
  • Contact: REN Xiang-Zhong E-mail:renxz@szu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21000174), Shenzhen Strategic Emerging Industry Development Funds, China (JCYJ20120613163733279, JCYJ20130329113849606).

摘要:

为了改善富锂锰基正极材料Li1.2Mn0.54Ni0.13Co0.13O2 的循环性能,采用燃烧法合成了正极材料Li1.2Mn0.54-xNi0.13Co0.13ZrxO2x=0.00,0.01,0.02,0.03,0.06). 通过X射线衍射(XRD)和扫描电镜(SEM)对其结构与形貌进行了表征,利用恒电流充放电测试,循环伏安(CV)及电化学交流阻抗谱(EIS)技术对其电化学性能进行测试. 结果表明,Li1.2Mn0.54-xNi0.13Co0.13ZrxO2x=0.00,0.01,0.02,0.03,0.06)正极材料均具有α-NaFeO2型层状结构;在室温,2.0-4.8 V电压范围,以0.1C和1.0C(充放电电流以1.0C=180 mA·g-1计算)倍率充放电进行测试,样品Li1.2Mn0.52Ni0.13Co0.13Zr0.02O2的首次放电比容量分别为280.3 和206.4 mAh·g-1. 其中,在1.0C倍率下,100次循环后容量保持率由原来的73.2%提高到88.9%;以5.0C倍率充放电进行测试,经50次循环后,掺杂正极材料的放电比容量为76.5 mAh·g-1,而未掺杂材料仅有15.0 mAh·g-1. 在50、25 和-10 ℃,2.0C倍率条件下,掺杂正极材料的电化学性能均得到有效改善,其中,在- 10℃ 经过50 次循环后正极材料Li1.2Mn0.52Ni0.13Co0.13Zr0.02O2比未掺杂的正极材料相比,其放电比容量提高了61.1%.

关键词: 燃烧法, 锂离子电池, 正极材料, 富锂材料, 掺杂

Abstract:

To improve the cycling performance of lithium-rich cathode materials, Li1.2Mn0.54Ni0.13Co0.13O2 and Li1.2Mn0.54-xNi0.13Co0.13ZrxO2 (x=0.00, 0.01, 0.02, 0.03, and 0.06) were synthesized by a combustion method. The structure and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical performances were examined by cyclic voltammetry (CV), electrochemical AC impedance spectroscopy, and galvanostatic charge-discharge cycling. The results indicate that all of the doped samples have a layer of α-NaFeO2. When charged and discharged at 0.1C and 1.0C (1.0C=180 mA·g-1) in the voltage range of 2.0-4.8 V, the initial discharge capacities of Li1.2Mn0.52Ni0.13Co0.13Zr0.02O2 were 280.3 and 206.4 mAh·g-1, respectively. Moreover, the capacity retention after 50 cycles improved from 73.2% to 88.9% at 1.0C at room temperature. Meanwhile, this system delivered a higher discharge capacity of 76.5 mAh·g-1 than that of the bare materials (15 mAh·g-1) at 5.0C after 50 cycles. Electrochemical performances of the doped samples were improved at a 2.0C rate at different temperatures (50, 25, and -10 ℃). Furthermore, compared with the undoped material, the specific discharge capacity increased by 61.1% at -10 ℃ after 50 cycles.

Key words: Combustion method, Lithium-ion battery, Cathode material, Lithium-rich material, Doping

MSC2000: 

  • O646