Preparation And Properties Of Lithium-ion Battery Cathode Materials LiNi_1/3Co_1/3Mn_1/3O₂

As a fresh generation of storage materials, lithium-ion battery emerges as times require with the environment problem and energy shortage issue getting serious. It has increasingly developed in recent years due to its high energy density, long cycle life, no memory effect, better stability, less toxicity and so on. The several disadvantages of traditional lithium-ion batteries limit the application. Therefore, assimilating the advantages of other lithium-ion batteries, LiNi1/3Co1/3Mn1/3O2 occupies unique space in marketing and science. In this novel, LiNi1/3Co1/3Mn1/3O2 is prepared by high-temperature solid state, solid state high temperature ball milling, sol-gel and sol-gel high temperature ball milling, and optimizes the materials made by solid state high temperature ball milling through tempering method. Besides, LiNi1/3Co1/3Mn1/3O2 has been investigated by XRD, SEM and electrochemical testing, respectively.LiNi1/3Co1/3Mn1/3O2 prepared at 800℃ for 10 hours in furnace presents the best performance. The first discharge capacity of LiNi1/3Co1/3Mn1/3O2 is 135.0 mAh/g and capacity loss is 15.1% at 0.1 C rate. After 40 cycles, capacity retention rate is 94.7% at 0.1C rate.After 2 hours high temperature ball milling, LiNi1/3Co1/3Mn1/3O2 has already had the hexagonal structure. The structure, morphology and electrochemical characters are promoted by tempering method. LiNi1/3Co1/3Mn1/3O2 prepared at 700℃ for 2 hours in ball milling and temperinged in furnace for 6 hours exhibits the best performance. The initial discharge capacity of LiNi1/3Co1/3Mn1/3O2 is 137.8 mAh/g and capacity loss is just 12.9%at 0.1 C rate. After 40 cycles, capacity retention rate is 89.9% at 0.1C rate.Using sol-gel method, LiNi1/3Co1/3Mn1/3O2 synthetised at 800℃ for 10 hours in furnace also represents the best performance. The first discharge capacity of LiNi1/3Co1/3Mn1/3O2 is 168.2mAh/g and capacity loss is just 10.1% at 0.1 C rate. After 40 cycles, capacity retention rate is unbelievable 96.6% at 0.1C rate.LiNi1/3Co1/3Mn1/3O2 has already had the hexagonal structure after 2 hours high temperature ball milling through sol-gel method. Tempering technology enhances several aspects properties of LiNi1/3Co1/3Mn1/3O2. Which prepared at 700℃ for 2 hours in ball milling and temperinged in furnace for 6 hours is the best. The first discharge capacity of LiNi1/3Co1/3Mn1/3O2 is 128.7 mAh/g and capacity loss is 17.8% at 0.1 C rate. After 40 cycles, capacity retention rate is 92.8% at 0.1C rate.