关键词: 锂离子电池, 正极材料, 溶胶-凝胶法, 电化学性能, 循环稳定性

Abstract:

The efficient recycling of valuable metals in spent lithium-ion batteries is the key to alleviate the contradiction between supply and demand of key metals. In this paper, the precursor of LiNi_1/3Mn_1/3Co_1/3O₂ ternary electrode material was prepared by leaching-sol-gel method using waste lithium-ion battery as raw material. The internal crystal structure and lattice morphology of electrode materials were analyzed and the electrochemical properties of the materials were also characterized. Results showed that the electrode material presented high sphericity and uniform particle size distribution, and the yield of -25μm particle size was 96.76% after calcination at 850℃ for 6h in CO₂ environment. Through the structural property analysis of the electrode material, it could be seen that the prepared material had a complete layered α-NaFeO₂ crystal structure, and the cation mixing degree was low, the layered structure was good, and the crystal structure of the material was clear lattice fringes and good crystallization degree. The electrochemical performance test results indicated that the prepared ternary materials exhibited excellent reversible discharge capacity and cyclic stability. The first discharge capacity of the electrode material reached 157.5mAh/g, and the reversible capacity remained at 141.6mAh/g after 160 cycles with a retention rate of 87%, which had the application prospect of commercial electrode materials.

Key words: lithium-ion batteries, cathode material, sol-gel method, electrochemical performance, cyclic stability