The Effect of Sintering Time on Electronic Conductivity of LiFeGdPO4/C as a Lithium-Ion Battery Cathode

Lithium iron phosphate (LiFePO4) is an alternative cathode material choice in lithium-ion batteries because of its non-toxic nature, high voltage (3.45 V), the high theoretical capacity of LiFePO4 (170 mAh/g), low cost, non-reactive and has good structural properties stability. However, LiFePO4 has a low electronic conductivity (10-9-10-10 S/cm) and a low diffusion coefficient of Li+ ions (10-12-10-14 cm2/s), so it affects electrochemical performance. There are several ways to increase the conductivity. These are namely carbon coating, metal ion doping and optimizing the sintering time. Optimal sintering time will increase crystallinity, thereby increasing the value of electronic conductivity. Then using the right sintering time will get a lot of the desired phase content. This study aims to determine the effect of the sintering time variation 6 hours, 8 hours, 10 hours, 20 hours and 30 hours to increase the electronic conductivity of LiFeGdPO4/C. The synthesis method used is the carbothermal reduction method with the precursors used are LiH2PO4, Fe2O3, Gd2O3 and carbon graphite. LCR meter and XRD are used to characterize samples. The results obtained indicate that the effect of sintering time can increase the value of the electronic conductivity of LiFeGdPO4/C, with the highest conductivity value at a sintering time of 30 hours of 1.5296 x 10-7 S/cm.