前驱体粒径对锂电三元材料LiNi0.8Co0.1Mn0.1O2性能的影响

Effect of particle size of precursors on properties of LiNi0.8Co0.1Mn0.1O2 materials for Li-ion batteries

用共沉淀反应合成了五种不同粒径的Ni0.8Co0.1Mn0.1(OH)2(NCM811-OH)前驱体,并采用高温固相反应制备了LiNi0.8Co0.1Mn0.1O2(NCM811)材料。通过研究前驱体的粒径对成品材料物化性能和电化学性能的影响发现,当NCM811-OH前驱体的中粒径D50大于6μm时,NCM811材料具有小的一次颗粒尺寸、小的比表面积和高的振实密度。电化学测试数据表明,由中粒径为10.04μm的前驱体制备的NCM811材料具有最好的电化学性能,在2.75~4.3V(vs. Li+/Li)电压范围内,0.1 C充放电倍率下放电比容量为202.0 mAh/g,100次循环容量保持率为96.9%;此外,高倍率放电时,NCM811-10在8 C/0.1 C的容量保持率为78.9%。

Ni0.8Co0.1Mn0.1(OH)2(NCM811-OH) precursors with different particle size were synthesized by co-precipitation method, and then LiNi0.8Co0.1Mn0.1O2(NCM811) were prepared by high-temperature solid state reaction. By studying the effect of particle size of precursors on the physicochemical and electrochemical properties of NCM811 materials, it is found that it has small primary particle size, small specific surface area, and high tap density only when the average particle size of the precursor is bigger than 6 μm. The electrochemical data show that the NCM811-10 material prepared from the precursor with the average particle size of 10.04 μm has the best electrochemical performance. Within the voltage range of 2.75~4.3 V(vs. Li+/Li), the specific discharge capacity at 0.1 C is 202.0 mAh/g with the 100 thcapacity retention of 96.9%. Besides, the capacity retention of 8 C/0.1 C is 78.9%.