The synchronous reutilization of the expired ferrous sulfate granules and waste Li foils for LiFePO4/C cathode

Abstract

Expired medicines and spent Li-anode batteries may result in the environment pollution and the waste of resource if they aren't reasonably recycled. In order to achieve the innocent treatment and the resource recovery, expired ferrous sulfate granules and waste Li foils were simultaneously recycled in the form of LiFePO4/C powders via the facile hydrothermal route. The obtained LiFePO4/C was investigated by methods of X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), energy dispersive X-ray spectrum (EDX), transmission electron microscope (TEM), galvanostatic charge/discharge and cyclic voltammetry (CV). As expected, the as-recycled LiFePO4/C powders consisted of many rod-like or sphere-like nanoparticles with the particle size about 60–400 nm. Furthermore, the resultant LiFePO4/C cathode delivered an initiate discharge capacity of 147.0 mAhg−1 at 0.1C and the reversible discharge capacity of 143 mAhg−1 after 50 cycles; even cycling at 5C and 10C for 500 cycles, the reversible discharge capacities remained about 123 mAhg−1 and 94 mAhg−1, respectively, comparable with those of pristine LiFePO4/C cathode. Obviously, the decent results may open a new way to develop the circular economy, which is very important in terms of the resource recovery and the environmental protection.