Recycling of LiCoO2 cathode material from spent lithium ion batteries by ultrasonic enhanced leaching and one-step regeneration

A novel process for recycling of spent LiCoO2 cathode materials has been developed. The novel process comprises an ultrasonic enhanced leaching and one-step regeneration of LiCoO2 materials with spray drying method. The ultrasonic is novelly applied for effectively improving leaching process of spent LiCoO2 materials in the system of DL-malic acid and H2O2. The leaching efficiencies of 98.13% for Li and 98.86% for Co were presented under the optimal condition of 1.5 mol/L DL-malic acid with 3 vol% H2O2, the solid/liquid ratio of 4 g/L, ultrasonic power of 95 W, temperature of 80 degrees C and leaching time of 25 min. Based on kinetic analysis, the ultrasonic enhanced leaching process is mainly controlled by the diffusion control model. Meanwhile, the product of Co(C4O5O5)(2) formed on particles surface of spent LiCoO2 materials during ultrasonic enhanced leaching process, which is provided from reaction mechanism analysis of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Finally, the regenerated LiCoO2 materials are regenerated in one step by spray drying from leaching solution, which present good electrochemical performance.

Automated summary

A novel process has been developed for recycling of spent LiCoO2 cathode materials, involving ultrasonic enhanced leaching and one-step regeneration through spray drying. The process shows high leaching efficiencies and is mainly controlled by the diffusion control model. The regenerated LiCoO2 materials exhibit excellent electrochemical performance based on reaction mechanism analysis.