The Influence of Polylactide Addition to The Performance of LifePO4/C Composite as Cathode Materials

Abstract

The polylactide and carbon addition to LiFePO4 has been studied to investigate the behavior of LiFePO₄/C composite. The cathode material of LiFePO₄ was prepared by coprecipitation of LiOH.H₂O, (NH₄)₂HPO_4, and FeSO₄.7H₂O solution. The resulting LiFePO₄ was mixed with biodegradable polymer PLA in the concentration of 6, 8, 10, and 12 % weight of the polymer. Heat treatment was done by heating the precursor at 700 ^o C for 4 hours. The physical chemistry properties of cathode materials were analyzed by using Simultaneous Thermal Analysis (STA), X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM), and Particle Size Analyzer (PSA) methods. High Precision LCR-meter was used to perform conductivity measurement, in which the LiFePO₄/C powder samples were prepared by using a 200 kg/cm² hydraulic press. TG analysis informs gradual weight decrease at LiFePO₄ temperature formation of 470 C and pyrolisis of remaining PLA occurs at 600 C. From all samples, XRD data indicate the pure phase of LiFePO₄. SEM image shows the uniform distribution particle of the sample with 6 % PLA content with a conductivity of 1.99 X 10^-2 Scm^-1.