Congratulations to Dr. Shuping Li's paper being accepted by the international authoritative journal "Nano Energy"! The title of the thesis is "Manipulating kinetics of sulfurized polyacrylonitrile with tellurium as eutectic accelerator to prevent polysulfide dissolution in lithium-sulfur battery under dissolution-deposition mechanism" Mechanism of dissolution of polysulfides).
The "solid state" mechanism can avoid the dissolution of polysulfides in lithium-sulfur batteries, but the reaction activity is limited. It is ideal to eliminate polysulfide dissolution under the "dissolution-deposition" mechanism, but it is difficult to achieve the use of S8 anode because of its inherent side reactions. However, vulcanized polyacrylonitrile (S@pPAN) is considered to involve only S3-4 and the soluble intermediate Li2S3-4, so the rapid and reversible conversion to insoluble Li2S2 and Li2S can avoid the dissolution of polysulfides. Here, Te is used as a eutectic accelerator in S@pPAN to accelerate the redox conversion and prevent the dissolution of polysulfides under the "dissolution-deposition" mechanism. In the TexS1-x@pPAN (Te doped S@pPAN) cathode, Te can be evenly distributed through the Te-S bond and accelerate the reaction, while providing capacity, so as to be compatible with ether and carbonate electrolytes, between 0.1 and 10 The specific capacity under A g-1 current density can be as high as 1507 and 861 mA h g-1, and it can be stably cycled in ether electrolyte for more than 600 cycles (the attenuation rate per cycle is 0.05%). 3.11 mg cm-2 sulfur load and 6 uL mg-1 electrolyte sulfur ratio also showed good performance. Further research confirmed that Te promotes the diffusion of Li ions and reduces the reaction resistance during charging/discharging, which significantly enhances the reaction kinetics and reduces the dissolution of polysulfides. This work shows that high-performance lithium-sulfur batteries operating under the "dissolution-deposition" mechanism do not dissolve polysulfides.
https://www.sciencedirect.com/science/article/pii/S2211285519302113?via%3Dihub
