Decommissioning, Characterization and Proposed Recycling Route of a Used Na-ZnCl₂ Battery Cell

Abstract

New battery technologies are necessary to cover the increasing demand for stationary energy storage as the green transition requires more use of renewable intermittent energy sources. The novel Na-ZnCl2 battery has been suggested as a solution to a cheap salt battery, exploiting abundant materials such as Na and Zn. It is, however, important to develop a recycling route for new batteries, making sure that end-of-life products do not go to landfill. This can be solved by reusing the materials (for the same or different applications/processes), or by recycling the materials. The present study has therefore investigated how Na-ZnCl2 battery cells can be safely decommissioned and recycled. After cycling the battery cell, microcomputed tomography (µCT) was used to map the distribution of the electrolyte. Followed, the cell was disassembled, and samples were analyzed by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive Spectroscopy (EDS), and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to characterize the used cell. It is concluded that the electrode materials and current collectors can be integrated in today’s recycling process of the state-of-the-art Na-NiCl2 battery. This is also the case for the solid β’’-Al2O3 membrane and the liquid NaAlCl4 electrolyte. Zn can be included in different processes, such as hot-dip galvanization.