LiMn2O4 prepared from waste lithium ion batteries through sol-gel process

The core issues that restrict the recycling of waste lithium-ion batteries (LIBs) are the difficulty of separation and the secondary pollution that occurs during the recycling process. In this paper, new LiMn2O4 (LMO) was prepared directly from the leaching solution of waste LIBs, which avoided the complex separation process. Citric acid was used as the leaching reagent, and glucose was used as the reducing agent. The structural properties of the resynthesized LMOs calcined at different temperatures were studied by X-ray diffraction (XRD) and further refined by the Rietveld method. XRD and Rietveld refinement confirmed that all the samples had cubic spinel structures, and the lattice parameters increased with increasing temperature. The surface morphology of the final products was characterized by SEM, TEM and XPS to determine the crystal structure, morphology and surface chemical constitution. The electrochemical properties were also tested. The results showed that the new LiMn2O4 prepared from waste LIBs possessed good electrochemical properties, and this method for recycling waste lithium-ion batteries is feasible.