Morphology-Dependent Electrochemical Performance of Carbon-Coated LIFEPO4 Particles Synthesized via Solvothermal Method

Abstract

Lithium iron phosphate (LiFePO4, LFP) has garnered significant attention as a cathode material for lithium-ion batteries due to its excellent safety, long cycle life, and low cost. However, its intrinsic low electronic conductivity and slow lithium-ion diffusion kinetics limit its widespread application. Carbon coating and morphology control are widely recognized strategies to overcome these limitations. This study investigates the synthesis of carbon-coated LiFePO4 (C-LFP) particles with tailored morphology via a facile solvothermal method, utilizing glucose as a carbon source. The as-synthesized C-LFP exhibits a uniform particulate morphology with an average particle size of approximately 200 nm, further confirmed by particle size distribution analysis. Detailed structural and morphological characterizations were performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy. Electrochemical performance was evaluated based on reported data from the literature, demonstrating excellent specific capacity (~160 mAh/g at 0.1C), superior cycling stability (capacity retention over 95% after extended cycles), and commendable rate capability (120 mAh/g at 5C). The enhanced electrochemical properties are attributed to the synergistic effect of optimized uniform particle morphology, which shortens Li+ diffusion pathways, and the robust carbon coating, which significantly improves electronic conductivity. This work highlights the critical role of morphology control in achieving high-performance LFP-based cathode materials.