【摘要】 以三元前驱体[Ni0.5Co0.2Mn0.3(OH)2]和Li2CO3为原料,采用预烧+高温固相法中试生产三元正极材料(LiNi0.5Co0.2Mn0.3O2)。X射线衍射光谱法(XRD)和扫描电子显微镜法(SEM)等物理检测表明合成的正极材料具有良好的α-NaFeO2层状结构,继承了Ni0.5Co0.2Mn0.3(OH)2的球形形貌;随着料层厚度的增加,材料粒度(D50)、振实密度(TD)、比表面积(BET)和残余锂含量的变化不明显。恒流充放电测试表明料层厚度对材料的电化学容量影响趋势小,在3.0～4.3 V区间,0.2 C充放电下的首次放电比容量大于165 mAh/g,1 C循环200次后的容量保持率为89.1%,组装的18650电池在3.0～4.1 V区间,1 C循环1 500次的容量保持率高达88.76%。更多还原

【Abstract】 Ternary cathode material(LiNi_0.5Co_0.2Mn_0.3O₂) was prepared by pre-calcination and high-temperature solid state method with ternary precursors [Ni0.5 Co0.2 Mn0.3（OH）2] and Li₂CO₃ as raw materials. X-ray diffraction（XRD）,scanning electron microscopy（SEM） and other physical tests show that the synthesized cathode material has goodα-NaFeO₂ layer structure and inherits the spherical shape of ternary precursor. The material particle size（D50）,tap density（TD）,specific surface area（BET） and residual lithium content do not significantly change with the increase of the material thickness. Galvanostatic charge-discharge tests show that the influence of the material thickness on the electrochemical capacity is not obvious, the first discharge specific capacity is more than 165 mAh/g at 0.2 C and the capacity retention is 89.1% after 200 cycles at 1 C when the voltage is between 3.0 and 4.3 V. The capacity retention of the prepared 18650 battery is 88.76% after 1 500 cycles at 1 C when the voltage is between 3.0 and 4.1 V.更多还原