Recovery of cathode materials from waste lithium iron phosphate batteries through ultralow temperature treatment and mechanical separation

Abstract

ABSTRACT Waste lithium iron phosphate (LFP) batteries consist of various of metallic and nonmetallic materials, with lithium being a critical strategic resource in the new energy era. Therefore, recycling LFP batteries has become a primary means of secondary lithium resource recovery. However, the presence of the strong binder polyvnylidene fluoride during the recycling process hinders the efficient recovery and separation of cell materials. This study proposes an innovative approach for recovery, involving ultralow temperature treatment and mechanical separation. In the experimental setup, the ultralow temperature treatment temperature at −140°C for 120 min, followed by 20 s of crushing, resulted in an impressive 96.5% dissociation rate of the cathode material and a purity of 94.2% for lithium iron phosphate. The physical and chemical changes in the cathode materials before and after ultralow temperature treatment were examined using differential scanning calorimetry, scanning electron microscopy, inductively coupled plasma optical emission spectrometer, X-ray fluorescence spectrometer, and X-ray diffraction (XRD). This method has the advantages of low cost, high efficiency, high environmental affinity and no additional products.