Tuning Ionic Conductivity and Thermal Stability in POMA-Enriched LLZO Composites for Next-Generation Lithium-Ion Batteries

Abstract

The garnet-type ceramic Li7La3Zr2O12 (LLZO) has garnered significant attention as a solid-state electrolyte for lithium-ion batteries due to its exceptional chemical stability, high ionic conductivity, and wide electrochemical window. Despite these advantages, practical applications of LLZO are hindered by challenges such as brittleness, interfacial resistance, and processing complexities. This study develops Sr- and Mg-doped LLZO enriched with poly(o-methoxyaniline) (POMA) composites. The composites were synthesized using a sonochemical approach, enabling uniform dispersion and integration of polymer and ceramic phases. Our results demonstrate that at an optimal 20% POMA content, the composite exhibited a remarkable enhancement in ionic conductivity (1.15 × 10-5 S/cm) along with exceptional thermal stability. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses confirmed the formation of amorphous domains that promote ion hopping, thermogravimetric analysis (TGA) highlighted the material’s operational resilience. Further, morphological studies revealed synergistic interactions between the ceramic and polymer phases, facilitating efficient lithium-ion transport. These findings present a potentially scalable and innovative strategy to enhance solid-state electrolytes, paving the way for safer, higher-capacity, and more durable lithium-ion batteries for next-generation energy storage systems.