Preparation and characterization of macroporous Li1.2Mn0.54Ni0.13Co0.13O2 cathode material for lithium-ion batteries via aerogel template
Preparation and characterization of macroporous Li1.2Mn0.54Ni0.13Co0.13O2 cathode material for lithium-ion batteries via aerogel template
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DOI：
10.1016/j.jpowsour.2013.04.006
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发表时间：
2013-10
影响因子：
9.2
通讯作者：
S. Shi;J. Tu;Yu Tang;Yi Zhang;X. Wang;C. Gu
中科院分区：
文献类型：
--
作者：
S. Shi;J. Tu;Yu Tang;Yi Zhang;X. Wang;C. Gu
以气凝胶为模板，采用固相反应法合成了六方有序的大孔Li 1. 2 Mn 0. 54 Ni 0. 13 Co 0. 13 O2正极材料。在800 °C、200 mA g − 1和2000 mA g− 1的电流密度下合成的富锂层状氧化物在2.0 V和4.8 V之间获得了244.0 mA h g− 1和153.9 mA h g− 1的高放电容量。将合成温度提高到900 °C，大孔Li1.2Mn0.54Ni0.13Co0.13O2在200 mA g− 1的电流密度下具有220.2 mA h g− 1的高放电容量，50次循环后的容量保持率为89.1%，在2000 mA g− 1的电流密度下具有129.8 mA h g− 1，并且在120次循环后几乎没有容量衰减。用恒电流间歇滴定法测得Li+在富锂层状氧化物中的扩散系数为5.0 × 10 - 18 - 8.0 × 10 - 14 cm ~ 2·s ~（-1）。电化学阻抗谱表明，层状氧化物的大孔结构和良好的颗粒接触可以提高其倍率性能和循环稳定性。
Macroporous Li1.2Mn0.54Ni0.13Co0.13O2cathode materials with high crystallinity and hexagonal ordering are synthesized by aerogel template followed by solid state reaction. High discharge capacities of 244.0 mA h g−1and 153.9 mA h g−1are obtained for the Li-rich layered oxide synthesized at 800 °C at current densities of 200 mA g−1and 2000 mA g−1between 2.0 V and 4.8 V. Increasing the synthesis temperature to 900 °C, the macroporous Li1.2Mn0.54Ni0.13Co0.13O2delivers a high discharge capacity of 220.2 mA h g−1at a current density of 200 mA g−1with a capacity retention of 89.1% after 50 cycles, 129.8 mA h g−1at a current density of 2000 mA g−1and almost no capacity fading after 120 cycles. The diffusion coefficients of Li+in the Li-rich layered oxide determined by galvanostatic intermittent titration technique are in the range of 5.0 × 10−18−8.0 × 10−14cm2s−1. Electrochemical impedance spectroscopy indicates that the macroporous structure with good particle contact of the layered oxide can improve its rate capability and cyclic stability.