Synthesis, characterization, and electrochemistry of cathode material Li[Li0.2Co0.13Ni0.13Mn0.54]O2 using organic chelating agents for lithium-ion batteries
Synthesis, characterization, and electrochemistry of cathode material Li[Li0.2Co0.13Ni0.13Mn0.54]O2 using organic chelating agents for lithium-ion batteries
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DOI：
10.1016/j.jpowsour.2012.11.099
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发表时间：
2013-04
影响因子：
9.2
通讯作者：
Taolin Zhao;Shi Chen;Li Li-Li;Xiaofeng Zhang;Renjie Chen;I. Belharouak;Feng Wu;K. Amine
中科院分区：
文献类型：
--
作者：
Taolin Zhao;Shi Chen;Li Li-Li;Xiaofeng Zhang;Renjie Chen;I. Belharouak;Feng Wu;K. Amine
以草酸、酒石酸（TA）和丁二酸（SA）为螯合剂，采用溶胶-凝胶法合成了锂离子电池正极材料Li[Li0.2Co0.13Ni0.13Mn0.54] O2。X射线衍射、扫描电子显微镜和X射线能谱分析表明，材料为单相化合物，具有良好的堆积性和层状α-NaFeO 2结构。TA材料具有最小的颗粒（0.2-0.3 μm），表面光滑，分布均匀。电化学研究表明，TA材料具有最高的初始放电容量（0.1 C时为281.1 mAh g− 1，2.0 C时为192.8 mAh g− 1），50次循环后的可逆容量（0.1 C时为240.5 mAh g− 1，0.5 C时为167.4 mAh g− 1）和最佳的倍率性能。SA材料的循环稳定性最好，在0.1 C和0.5 C下循环50次后容量保持率分别为87.4%和80.1%。循环伏安法和微分容量曲线表明，Mn ~（4+）/Mn ~（3+）还原峰出现在第一次放电过程中，随着循环次数的增加，还原峰变得更加明显，形成尖晶石结构。电阻抗谱证实TA材料的低电荷转移电阻是其上级放电容量和倍率性能优异的原因。
Oxalic acid, tartaric acid (TA), and succinic acid (SA) are studied as chelating agents for sol–gel synthesis of Li[Li0.2Co0.13Ni0.13Mn0.54]O2as a cathode material for lithium-ion batteries. X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy show that the materials are single-phase compounds with good crystallinities and layered α-NaFeO2structures. The TA-material has the smallest particles (0.2–0.3 μm), with a smooth surface, and uniform distribution. Electrochemical studies indicate that the TA-material exhibits the highest initial discharge capacity (281.1 mAh g−1at 0.1 C, 192.8 mAh g−1at 2.0 C), the highest reversible capacity after 50 cycles (240.5 mAh g−1at 0.1 C, 167.4 mAh g−1at 0.5 C), and the best rate performance. The cycling stability of the SA-material is the best, with capacity retentions of 87.4% at 0.1 C and 80.1% at 0.5 C after 50 cycles. Mn4+/3+reduction peaks appear at the first discharge process and become more evident with increasing cycle number, resulting in a spinel structure, as proved by cyclic voltammetry and differential capacity curves. Electrical impedance spectroscopy confirms that the low charge-transfer resistance of the TA-material is responsible for its superior discharge capacity and rate performance.