Watermelon Flesh‐Like Ni₃S₂@C Composite Separator with Polysulfide Shuttle Inhibition for High‐Performance Lithium‐Sulfur Batteries

Abstract

The shuttle effect limits the practical application of lithium‐sulfur (Li‐S) batteries with high specific capacity and cheap price. Herein, a three‐dimensional carbon substrate containing Ni3S2 nanoparticles is created to modify the separator. The in situ optical visualization battery proves that the material can realize the rapid conversion of Li2S6. Moreover, the impact of lithium‐ion diffusion on the reactions in the cell is investigated, and the mechanism of Ni3S2@C in the cell is proposed based on the “adsorption‐diffusion‐conversion” mechanism. The “adsorption‐diffusion‐conversion” process of polysulfide is carried out on the surface of the composite separator, showing positive effects on the inhibition of polysulfide shuttle and the promotion of conversion. The separator is modified to improve sulfur utilization and reduce dead sulfur accumulation through a strategy of chemical immobilization and physical blocking. This helps to bridge the existing gaps of Li‐S batteries.

Amorphous/crystalline heterostructure design enables highly efficient adsorption–diffusion–conversion of polysulfides for lithium–sulfur batteries

“…5h and listed in Table S2. † 8,14,15,[48][49][50][53][54][55][56][57][58][59][60][61][62][63][64] To fulll the demand for practical applications of Li-S batteries, the electrochemical performance at high sulfur loading was investigated. Fig.…”

Advanced Separator Materials for Enhanced Electrochemical Performance of Lithium–Sulfur Batteries: Progress and Prospects

“…They accurately tracked the volumetric and micro−morphological changes of the active material particles during the charge−discharge process using in situ SEM and energy−dispersive X−ray spectroscopy while repeatedly disassembling the battery electrodes. Zhang et al 175 visualized the changes of polysulfides in symmetric batteries through in−situ optical image visualization. Additionally, they examined the adsorption effect of the Ni 3 S 2 @C Separator on LiPSs by configuring different concentrations of electrolytes.…”

Accelerated Sulfur Redox Kinetics on Transition Metal Sulfide Electrocatalysts by Modulating Electronic‐State of Active Sites

“…[7] Zhang et al reported on the fabrication of Ni 3 S 2 nanoparticle electrocatalysts with abundant active sites, which are capable of strengthening the chemical affinity of LiPSs and boosting their reaction kinetics based on the "adsorptiondiffusion-conversion" mechanism. [8] To further upgrade the Li-S battery performance in terms of the high-rate capability and long cycling stability, several efficient methods, including the anion defects, [9] heterointerface engineering, [10] and cation doping strategy [11] , etc., have been demonstrated to greatly improve the adsorption and catalytic conversion of LiPSs on the TMS with tailored surface/interface structure. Although these advances, the electrochemical performance of Li-S batteries with different kinds of TMSs varies considerably, the intrinsically active descriptor of these TMSs and their surface/interface structureactivity relationship for Li-S batteries are still not well revealed.…”