Innovative methodology for advanced battery recycling research demonstrated with electrochemical extraction

Abstract

Environmentally friendly processes to recapture critical metals and supplement markets are vital to overall sustainability in the energy sector. This work outlines a precise methodology for the electrochemical study of extraction performance in hydrometallurgical recycling. To demonstrate this method, the battery cathode material NMC532 is exposed to hydrochloric acid solutions at varying concentrations, rotation rates, current densities, and hydrogen peroxide contents. A dispersion of NMC532 and Nafion™ in water is deposited onto a rotating disc electrode surface to form a thin-film composite. The solution is sampled over time and relevant component concentrations are measured using inductively coupled plasma mass spectrometry (ICP-MS). The solution volume is maintained by replacing the sampled volume with initial solution and a correction equation is used to account for dilution. After electrochemical extraction, the NMC532 residue is collected for further analysis using scanning electron microscopy (SEM). This methodology requires minimal recyclable material to assess a wide variety of extraction conditions and provide various high-precision results. It can also facilitate the development of advanced electrochemical systems and provide valuable insight into key mechanisms for various hydrometallurgical and electrochemical processes.