![]() After that, people discovered that the heteroelements (such as N, P, O, or B elements)-doped carbon materials can significantly extend battery cycle life without decreasing the specific capacity of batteries. Thus, the carbon materials with all kinds of micromorphologies are considered as the ideal host materials for the sulfur cathode materials. In the early stage of Li–S battery research, the researchers found that using conductive carbon materials can enhance the utilization rate of insulated sulfur. Through the unremitting efforts of researchers, the cyclic performances of Li–S batteries with ester-based electrolytes gradually approached their theoretical specific capacity (1675 mAh g −1) in the laboratory, and the most commonly used modification method of sulfur cathode materials is compounding with the functional host material to form the composites (M is the host material). During this period, the research focus of Li–S batteries went through the process from the selection of electrolyte, to the modification of sulfur cathode materials, and then to the treatment of lithium metal anode materials. ![]() Since Herbert and Ulam first proposed the concept of Li–S batteries in 1962, the research process of these kinds of cells passed nearly 58 years. ![]() Finally, the remaining challenges, such as the fundamental studies and commercialized applications, as well as the future research directions are discussed. Herein, the surface/interface structure and chemistry of sulfur host materials involving structural factors and adsorption/conversion mechanisms of LPS (based on DFT calculation) on the interface are demonstrated. The functional hosts are used to prevent the polysulfide shuttle or catalyze Li–S conversion reactions (enhance the reaction kinetics), and density functional theory (DFT) is used to understand the mechanism of the interaction between host and polysulfides. The reason is that the adsorption/conversion of LPS mainly occurs on the surface/interface of host materials. In the research of Li–S batteries, it is observed that the surface/interface structure and chemistry of sulfur host materials play significant roles in the performance of Li–S batteries. However, the low conductivity of sulfur, the shuttle effect of lithium polysulfide (LPS), and inadequate safety caused by lithium dendrite formation limit their practical applications. Lithium–sulfur (Li–S) batteries with an ultrahigh energy density (2500 Wh kg −1) are considered the most promising candidates for next-generation rechargeable batteries. Nowadays, the rapid development of portable electronic products and low-emission electric vehicles is putting forward higher requirements for energy-storage systems.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |