چكيده به لاتين
Sodium-ion batteries have been proposed as a promising alternative to lithium-ion batteries due to the abundance and wide distribution of sodium sources as well as similar electrochemical performance. The cathode studied in this dissertation is part of NASICON structures, which is in the group of poly-anionic cathodes and its chemical formula is Na3V2 (PO4)3. In this study, by the use of CTAB, PVP as fuel, the use of various solvents such as ethanol, methanol and glycerol and the use of additives such as citric acid and their combination with cathode materials, the samples were synthesized. The initial capacities of CTAB 1mmol and CTAB1.5 mmol at 0.1 C were equal to 123.27 and 108.29 mAhg-1, respectively. The capacity retention percentages for CTAB 1mmol and CTAB 1.5 mmol were obtained after 50 cycles of 90% and 91%, respectively. In the second part of the experiment, the effect of PVP fuel on the performance of the synthesized cathode material was investigated. The use of PVP material with a value of 1.5 mmol showed an initial capacity of 92.05 mAhg-1 at 0.1C and PVP 1 mmol showed an initial capacity of 101.84 mAhg-1. PVP with a value of 1.5 mmol was able to maintain 96% of its initial capacity after 50 cycles at 1C, while the PVP 1 mmol retained 79% of its capacity. Subsequently, in the synthesis of cathodic material with the amount of CTAB 1 mmol with different solvents, it was observed that the material synthesized in glycerol solvent showed initial capacity of 113.53 mAhg-1, ethanol solvent showed initial capacity 105.24 mAhg-1 and methanol solvent showed initial capacity equal to 100.35 mAhg-1 at 0.1C. Methanol solvent has improved the stability of the synthesized cathode compared to methanol and glycerol solvents, however, the CTAB 1 mmol synthesized in aqueous solvent showed better cyclic stability than the other three solvents. Capacity maintenance rate For the water solvents, methanol, ethanol and glycerol are equal to 90%, 82%, 77%, 70%, respectively. Using the citric acid as additive to the CTAB sample synthesized in water, the initial capacity of 107.8 mAhg-1 was obtained at 0.1C and the stability of the cathode synthesized with CTAB 1 mmol was significantly improved and this cathode was able to maintain 98% of its initial capacity after 50 cycles at the 1C.
