Due to their high specific theoretical energy density, lithium-sulfur batteries are one of the promising candidates for energy storage in the future. However, in practice, they face a number of challenges, such as poor sulfur conductivity, polysulfide solubility, dendrite formation on the anode surface, and cathode instability. As part of the thesis, we compared the performance of two carbon hosts – ENSACO mesoporous carbon and turbostratic “flash” graphene (tFG) – in composites with sulfur. The prepared samples were analyzed using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), contact angle measurement to determine wettability, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and galvanostatic discharge and charge measurements at different current rates. The use and comparison of two different ether electrolytes also played an important role: 1M LiTFSI in TEGDME:DOL and 1M LiTFSI in TFEE:DOL. Based on the results, we determined the importance of the structure and properties of the carbon host in terms of wettability, sulfur retention, and battery performance. The obtained data allows us to better understand how the performance of Li–S batteries can be improved by selecting the appropriate materials.
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