Synthesis of Spherical Graphite Particles and Their Application as Cathode Material in Dual-Ion Cells

Abstract

In this work, carbon spheres having an average particle diameter of 0.6 µm were prepared by a simple hydrothermal synthesis method using glucose as precursor. These carbon spheres were carbonized and graphitized at different temperatures, namely 1200 °C, 2100 °C, 2400 °C and 2800 °C, in order to study the impact of the carbon structural properties, i.e. particle morphology and degree of graphitization, on the TFSI- anion intercalation behavior into these graphitized carbons used as cathode material in dual-ion cells. The structural properties of the carbon spheres, such as particle size, surface morphology, specific surface area and crystallinity after heat-treatment are characterized by scanning electron microscopy, X-ray diffraction and nitrogen adsorption measurements. Consequently, the structural characteristics are correlated to the electrochemical results for application as cathode material in dual-ion cells. In this context, a high degree of graphitization is mandatory to achieve a high reversible capacity.