Carbon materials in lithium sulfur batteries

G. LUQUE, S. RAVIOLO, F. GARCÍA SORIANO, G. LENER, M. ROJAS, P. VÉLEZ, MARTIN E. ZOLOFF MICHOFF, FLAVIA E. LOBO MAZA, J. LUQUE DI SALVO, G. DE LUCA, D. BARRACO,; V. BRACAMONTE,; A. CALDERÓN; E. LEIVA

Conferencia; 2nd International Conference on Carbon Chemistry and Materials (CCM-2022); 2022

Lithium–sulfur batteries (Li-S) are among the most promising electrochemical energy storage devices of the near future. The main reason is due to the low price, abundant availability, environmental friendliness of sulfur, as cathode material and its high theoretical capacity in comparison to lithium-ion technologies. Nevertheless, Li-S batteries face many challenges that have to be overcome in order to replace li-ion batteries. A Li-S battery typically consists of a sulfur cathode and a metallic lithium anode with a porous separator and a non-aqueous electrolyte in between. During discharge, lithium ions are formed at the anode and migrate to the cathode side, whilst the electrons move from the anode to the cathode through the external circuit. Sulfur is reduced to lithium sulfide [1], and the opposite takes place during charging. One of the main problems of this type of batteries is the insulating nature of sulfur, being mandatory to embed it into a conductive material. In this sense carbon materials, has many advantages such as low cost, wide window potential, versatility, etc. They can also mitigate the volume expansion that take place during discharge. Another problem of Li-S batteries lay on the high solubility of long chain polysulfides that form during cell function and shuttle between anode and cathode. This can be overcome by using functionalized carbon materials in/on the cathode, or modifying the separator as polysulfides barrier [2]. In the present work, we present experimental and computational studies performed in our lab with the objective of overcoming the different problems that Li-S batteries present, by means of using different carbon based materials.