Traditional lithium-ion batteries are limited by liquid electrolytes, prompting a shift towards solid-state electrolytes that provide enhanced thermal stability and safety features.

Recent research highlights the production of Y-doped Lithium Aluminum Titanium Phosphate (LATP) nanoparticles via spray-flame synthesis (SFS), a method that allows for scalable and cost-effective continuous production.

SFS not only enables high phase purity and specific surface area in nanoparticles but also standardizes the production of high ionic conductive LATP materials for advanced solid-state battery applications.

The study specifically investigates the impact of Y3+ doping on the ionic conductivity and chemical stability of Li1.3Al0.3−xYxTi1.7(PO4)3 (LAYTP-x) materials.

Findings reveal that the ionic conductivity of LATP significantly increases with Y doping, from 0.1 mS/cm for undoped samples to 0.84 mS/cm for LAY0.1TP samples at room temperature.

The introduction of Y3+ not only improved the density of the ceramics but also enhanced conductivity, with LAYTP-0.03 achieving a relative density of 95.8%.

Among the samples, LAYTP-0.03 exhibited the highest total conductivity of 2.03 × 10⁻⁴ S cm⁻¹ and a low activation energy of 0.33 eV, making it suitable for solid-state batteries.

Electrochemical Impedance Spectroscopy (EIS) results indicated that grain boundary resistance significantly affects ionic conductivity, which decreases with optimal levels of Y3+ doping.

The optimization of grain size and distribution through Y3+ doping further enhances the overall electrochemical performance of the materials.

When paired with the NCM811 cathode, the Li/LAYTP-0.03/NCM811 cell demonstrated excellent electrochemical performance, achieving a capacity of 155 mAh/g after 50 cycles with nearly 100% Coulombic efficiency.

Future research will focus on addressing interface issues between electrolytes and electrodes to further improve battery performance.

The study emphasizes the careful selection of annealing temperatures to balance ionic conductivity while minimizing the formation of unwanted impurity phases during the synthesis process.