THE EFFECT OF FLUORINE DOPING AND CALCINATION TEMPERATURE ON Li4Ti5O12/C MATERIAL USING SOLID STATE METHOD

Abstract - Li 4 Ti 5 O 12 /C anode has advantage of stable operating voltage compared to graphite which cannot be used in high rate power conditions and the dimensions of graphite change when first charging. Addition of F - to Li 4 Ti 5 O 12 anode can improve electrochemical performance and influence the morphology of the anode Li 4 Ti 5 O 12 . In this study a synthesis process was carried out and the addition of variations of F (0.1; 0.15; 0.2 moles) into Li 4 Ti 5 O 12 anode using the solid state reaction method. Then the calcination process was carried out with temperature variations of 700, 750 and 800°C. The reaction product is coated with carbon sourced from acetylene and argon gas. The XRD results show the highest peak at 2θ around 17-20°. The addition of F has been successfully carried out on LTO material. Ion F has been incorporated into the LTO crystal structure by substituting O ions without causing changes in the crystal structure characteristics. The presence of element F causes the XRD peak to change in a lower direction so that it becomes more crystalline, with the smaller lattice parameters and unit cells. SEM testing result was carried out to determine the morphology of anode Li 4 Ti 5 O 12 /C material. At calcination temperatures of 700 and 750°C the Li 4 Ti 5 O 12 /C particles had irregular sphere shaped with nanometer size and homogeneous distribution. However, at a calcination temperature of 800°C agglomeration occurred, so that the particles adhere to each other and enlarge. This condition affects the electrochemical performance of the sample.