CoP/C Nanocubes-Modified Separator Suppressing Polysulfide Dissolution for High-Rate and Stable Lithium–Sulfur Batteries

Abstract

A functioned PP was chosen as a separator to suppress the shuttling effect of soluble polysulfide in lithium−sulfur batteries (LSBs). Nanocubic cobalt phosphide/carbon (CoP/C) was modified on PP membrane through a simple vacuum filtration method. This CoP/C-modified PP separator not only efficiently captures polysulfides through strong chemical affinity but also facilitates the conversion of the soluble intermediates due to the fast transfer at the interface. In consequence, the cell with a CoP/C-modified separator exhibits a lowcapacity decay of only 0.08% per cycle over 500 cycles at 1 C with an initial capacity of 938 mAh g −1 and a superior rate performance of 594 mAh g −1 at 4 C. Even with a high loading of 3.2 mg cm −2 , the cell still exhibits an excellent reversible capacity of 601.3 mAh g −1 after 100 cycles at 0.5 C. This work provides a new strategy to effectively restrict the polysulfide shuttling.

Multifunctional FeP/Spongy Carbon Modified Separator with Enhanced Polysulfide Immobilization and Conversion for Flame‐Retardant Lithium‐Sulfur Batteries

“…[21,22] Moreover, the mild preparation process of TMPs is easier than metal carbides and metal nitrides. As reported in the literature, Zhao [23] proved that CoP can efficiently adsorb the polysulfides and improve the transformation of sulfur chemistry. The optimized CoP/C modified separator exhibits an ultralow capacity decay rate of 0.08 %.…”

Conductive FeOOH as Multifunctional Interlayer for Superior Lithium–Sulfur Batteries

“…The carbon materials can interaction with LiPSs via only weak van der Waal's force, [ 7 ] where solid Li 2 S 2 /Li 2 S will easily precitate and accumulation at the seperator as an insulating layer, further hindering the Li ion diffusion process. [ 35 ] The fast diffusion kinetics is related to the strong immobilized and effective catalytic conversion of LiPSs, driving fast Li ion diffusion toward various S species. [ 19 ] In the multielectron‐involved redox process, if the LiPSs cannot be effectively achnored or sluggish redox reaction is happened, LiPSs will be consumed in the electrolyte to lower S utilization and simulately increase electrolyte viscosity to dynamically slow down the electrochemical reaction rate especilally at high rates.…”

Functionally Modified Polyolefin-Based Separators for Lithium-Sulfur Batteries: Progress and Prospects

“…As a typical representative of phosphide, cobalt phosphide (CoP) can catalyze the conversion of polysulfide and dramatically increase the sulfur utilization. Lin et al (Lin et al, 2020) modified a PP separator by co-coating CoP and carbon on the surface of a PP separator as illustrated in Figure 5A. According to the XPS results ( Figure 5B), the CoP/C-coated separator could localize the insoluble polysulfide on the cathode by strong interactions between Co. atoms derived from CoP and S atoms in the Li 2 S 6 solution.…”

“…Benefiting from the efficiency and durability of the energy storage system, portable electronic and smart electronic fields have been devoted to developing minimization for meeting the fast-increasing requirements of human to novel electrified products. Nevertheless, the present-day commercialized lithium-ion batteries (LIBs) are difficult to satisfy the large-scale application of smart grids and electric vehicles due to its high cost and low energy density (<300 Wh kg −1 ) (Fang et al, 2018;Lin et al, 2020). Therefore, under the premise of the scalable utilization of a high energy density battery system, lithiumsulfur batteries (LSBs) with the advantages in large energy density (>500 Wh kg −1 ), high natural abundance, inexpensive and nontoxicity are one of the most fascinating battery candidates (Liu et al, 2017b).…”

“…FIGURE 5 | (A) Schematic illustration of fabrication procedure of CoP/C nanocube and cell configuration of the LSBs employing the CoP/C coated separator (B) High-resolution XPS spectrum of Co 2p and P 2p before and after CoP/C interacting with Li 2 S 6 (C) Performance comparison of LSBs with different separators. Reproduced with permission from(Lin et al, 2020). Frontiers in Energy Research | www.frontiersin.org November 2020 | Volume 8 | Article 593640…”