Preparation And Modification Of Ternary Cathode Materials For LiNi_0.8Co_0.1Mn_0.1O₂

With the increasingly serious global energy crisis and environmental problems,in order to solve these problems,people have been seeking the development of various clean new energy sources.For this reason,our country is vigorously developing the new energy vehicle industry,and lithium-ion batteries have been receiving widespread attention as a power battery in electric vehicles.As an indispensable and important part of lithium-ion batteries,cathode materials have also received close attention from scientific researchers,hoping to obtain cathode materials with excellent performance to meet people’s needs.After analyzing the current status of various cathode materials,the subject selected LiNi_0.8Co_0.1Mn_0.1O₂（NCM811）ternary cathode materials as the research object for synthesis and modification research,and achieved these results.First of all,in view of the complex process and large amount of wastewater generated by the co-precipitation method currently used in industrial production,we have successfully synthesized the pure phase NCM811 material by using a nano-milling assisted solid-state approach,and optimized the ball milling in the process parameters such as time and calcination temperature.After the electrochemical performance test,the discharge specific capacity in the first cycle was 184.5 m Ah·g^-1,and the coulombic efficiency in the first cycle was 79.23%.After 50 cycles,the capacity was 158.5 m Ah·g^-1,and the capacity retention rate was 85.9%.In order to further improve the electrochemical performance of the material,we have carried out boron modification studies on the material.Using boron to replace part of the transition metal,XRD and SEM tests had found that boron can well enter the crystal lattice and promote the growth and development of the crystal.Reduce the intensity ratio of I（003）/ I（104）,and reduce the situation of lithium-nickel mixed discharge.Among the synthesized samples,Li(Ni_0.8Co_0.1Mn_0.1)_0.99B_0.01O₂ showed the best electrochemical performance,which was 194.7 m Ah·g^-1 and 166.8 m Ah·g^-1 at 0.1C and 5C,respectively.After 100 cycles,the capacity retention rate at 0.5 C is 98.2%,and it has the best rate performance.Compared with NCM811 materials reported elsewhere,the materials obtained by this method show high potential for future applications.