Low-cost Li2S-based cathode for lithium sulfur battery

Low-cost lithium-sulfur batteries (LSBs) with high specific energy density have drawn the attention of the industrial community as lithium-ion batteries get closer to their theoretical limits. However, their commercialization is constrained by the use of lithium metal anodes and the shuttle effect of lithium polysulfides (LiPSs) in redox processes. Ketjenblack (KB) was used in this research work to embed cobalt nanoparticles with a diameter smaller than 40 nm in order to create a suitable and affordable cathode host. Incorporating Co nanoparticles with KB that has a porous structure and great electrical conductivity allows the host to confine LiPSs chemically and physically, which is beneficial for lowering the shuttle effect and lengthening the lifespan of LSBs. Additionally, by using the lithiated form of sulfur (Li2S) rather than sulfur as the cathode material, the lithium source was moved from the anode to the cathode, reducing the safety concerns related to Li metal anodes and enabling the use of non-metallic anode materials like silicon and tin in LSBs. Li2S-Co@KB cathode has an initial discharge capacity of 850.3 mAh gLi2S-1. The cell has shown strong cycling stability at a 0.5 C current rate for over 300 cycles, with low capacity fading of 0.19% per cycle, as well as exceptional C-rate performances up to 5 C.