DEVELOPMENT OF BORIDES/BORATES FOR ENERGY STORAGE DEVICES

2022-9
Bahtiyar, Doruk
For many years, materials in the form of metal sulfides, oxides, phosphates, and titanates have been developed as cathode and anode active materials to be used in energy storage devices. Borides and borates, recently, attracted the attention of researchers in this field. In this study, for the development of a new class of materials for energy storage applications, synthesis and characterization of metal (Fe, Mo, Mn, and V) borides and (Mn, and Y)borates were carried out. The obtained materials were tested for their activity in lithium-ion batteries. Chemical and structural analysis were performed using X-ray diffraction spectroscopy, and scanning electron microscopy. Electrochemical characterization of the cells showed that manganase boride has the highest initial specific capacity of 576.80 mAh/g while yittrium borate has a specific capacity of 78.54 mAh/g as lowest at 20 mA/g current density. After fifty cycles at 20 mA/g, capacity decrease was observed for all samples, capacity retention of VB was calculated as 85.37 % which was the highest among all samples that are synthesized during this study. Furthermore, cyclic voltammetry was applied to understand charge-discharge mechanism of samples. It was noted that all samples has SEı formation around 0.74 V.

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Citation Formats
D. Bahtiyar, “DEVELOPMENT OF BORIDES/BORATES FOR ENERGY STORAGE DEVICES,” M.S. - Master of Science, Middle East Technical University, 2022.