Analytical and structural characterization of waste lithium-ion batteries for their effective recycling strategy

Lithium-ion batteries (LIBs) are crucial for energy storage but pose environmental and health risks due to toxic materials like lithium, cobalt, and nickel. Their rapid increase raises concerns about soil and water contamination from improper disposal, highlighting the need for effective recycling. Developing strategies requires understanding their chemical and structural composition, as well as assessing battery safety and integrity to minimize risks during processing. This study presents a comprehensive analytical and structural characterization of waste LIBs to apprise recycling processes using techniques including Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Energy Dispersive X-ray (EDX), and Fourier Transform Infrared Spectroscopy (FTIR) to investigate the phase changes, material degradation, and chemical composition of the cathode, anode, electrolyte, and binder materials in spent LIBs. SEM micrographs and EDX mapping of LIB residues at 1000× and 1500× magnifications showed rough, spherical particles with a uniform size distribution of 10–12 μm. These particles, identified as metal and metal oxide components from the cathodes, play a key role in influencing microbial interactions and enhancing metal recovery efficiency during bioleaching. XRD patterns indicated the crystalline structures of LiCoO₂, with a dominant peak at 2θ = 26.39°. At the same time, Li (Ni Co Mn) O₂ exhibited distinct peaks at 2θ = 18.7°, 26.39°, 44.46°, and 66.18°, with some overlapping with LiCoO₂ at lower intensities. The FTIR spectrum provided insights into the chemical composition and molecular structures supporting the recycling of LIBs by offering critical information to improve material recovery, optimize processes, and enhance sustainability. This study underscores the importance of characterization in developing sustainable and cost-effective recycling strategies for LIBs.