(603h) Influence Mechanism of Al3+ Doping on LiFePO4 Performance: Suppression of Anti-Site Defects and Industrial Implications for Battery Recycling

In this study, a group of aluminum-doped Li_1-3xAl_xFePO₄/C with varying dopant concentrations were synthesized via a solid-state reaction. Electron Dispersive Spectroscopy (EDS) analysis revealed a uniform distribution of aluminum dopants across the crystals of the synthesized samples. X-ray diffraction (XRD) analyses with Rietveld refinement, and Fourier-Transform Infrared Spectroscopy (FT-IR) showed that minimal aluminum doping effectively mitigates the formation of anti-site defects within the LFP structure, reducing the defect to an very low level compared to that in the undoped LFP, thereby enhancing the lithium-ion diffusion rate by facilitating a clearer [010] path for ion diffusion. The performance improvement was significantly evident under rapid charge and discharge conditions. This study illuminates the beneficial effects of aluminum doping on the electrochemical characteristics of LFP cathodes, providing valuable insights for the enhancement of lithium-ion battery performance and the effective management of aluminum impurities in battery recycling processes.