622镍钴锰酸锂包覆偏硼酸改性试验研究

Experimental Study on the Modification of 622 Ni-Co Lithium Manganate Coated with Metaboric Acid

摘要: 本实验采用高温固相法经二次烧结合成622三元正极材料，对NCM622单晶前驱体合成的NCM622镍钴锰酸锂正极材料进行硼包覆实验，硼包覆物采用偏硼酸，将NCM622正极材料与0.1 wt%、0.2 wt%、0.5 wt%、1 wt%的偏硼酸混合研磨后，以700℃ * 5 h烧结下进行包覆处理，探究在不同硼含量的条件下对NCM622正极材料性能的影响。试验结果显示，当烧结温度为700℃，烧结时间为6 h，硼包覆含量为0.50%时为最优工艺条件，此条件下的622三元正极材料的粒度为10.99 μm，振实密度为2.68 g/cm³，1C容量为166.57 mAh/g，60次循环容量保持率为98.48%，此时的622三元正极材料所制备的锂离子电池综合性能较好，达到最佳包覆效果。

Abstract: This experiment adopts the high temperature solid state method through second sintering synthetic 622 NCM cathode material. Boron coating experiments were carried out on NCM622 cathode material which is synthesized from NCM622 single crystal precursors, coated boron content using metaborate. The NCM622 cathode material was mixed and ground with 0.1 wt%, 0.2 wt%, 0.5 wt%, and 1 wt% metaboric acid, and then sintered at 700˚C * 5 h for coating treatment to explore the influence of different boron content on the properties of NCM622. Test results showed that when the sintering temperature is 700˚C, sintering time 6 hours, and the condition of coated boron content 0.5%, the process conditions are optimal. Under this condition, the particle size of 622 ternary material is 10.99 μm, the density of vibration is 2.68 g/cm³, the 1C capacity is 166.57 mAh/g, and the retention rate of 60 cycles is 98.48%. At these conditions, the comprehensive performance of the lithium ion battery prepared by the 622 ternary material is good, achieving the best coating effect.