The formation of lithium (Li) dendrites across the separator in lithium-ion batteries (LIBs) poses a significant short-circuit hazard. Conventional separator materials often fail to meet the evolving safety standards for next-generation LIBs. This study presents aluminum nitride modified polyethylene terephthalate (AlN/PET) composites, synthesized from recycled PET via an electrospinning technique, aimed at enhancing dendrite suppression. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the encapsulation of AlN nanoparticles within the PET micro/nanoarchitecture. Thermogravimetric analysis determined the AlN content to be approximately 4-5 wt%. Characterization by X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) validated the structural integrity of the PET/AlN composites. Notably, the PET/AlN 5 wt% composite exhibited 69.23% porosity and a high electrolyte uptake of 521.69%. Electrochemical tests at 0.5C revealed a reversible specific capacity of 241.7 mAh g⁻¹ after 100 cycles. C-rate capability assessments showed average specific capacities of 246.5, 225.1, 208.2, 179.2, and 116.5 mAh g⁻¹ at 0.2, 0.5, 1, 2, and 4C, respectively. The enhanced electrochemical performance is attributed to the synergistic effects of AlN nanoparticles, micro/nanoarchitectures, and mesoporous structures, facilitating efficient Li ion transport and ensuring hydrothermal stability. This study highlights the potential of PET/AlN composites as effective and safe separator materials for advanced LIB applications.

鳴謝

This work was supported by a grant  from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project number: UGC/FDS25/E06/19).