Sulfur Immobilization by “Chemical Anchor” to Suppress the Diffusion of Polysulfides in Lithium–Sulfur Batteries

Abstract

Lithium–sulfur (Li–S) battery is considered to be one of the most promising contenders for the next generation high‐energy storages due to their high theoretical energy density (≈2600 Wh kg−1), which is nearly five times higher than that of the commercial LiCoO2/graphite batteries. However, a series of issues especially for the dissolution of lithium polysulfides (LiPSs) and their “shuttle effect” greatly limit their widely commercial applications. Starting from a brief overview of conventional methods to solve these problems, the achievements spotlighted in this review mainly show that the diffusion of LiPSs can be effectively suppressed by forming strong “chemical anchor” between LiPSs and host materials. The synthetic methods and characterization techniques are reviewed according to different types of chemical bonding between LiPSs and the host materials. Theoretical calculation methods are also summarized here to further understanding the role of these “chemical anchors.” Proposing with some perspectives and future research efforts, this review is hoped to provide an in‐depth understanding and offer avenues in the rational design of Li–S batteries with long cycle life and high energy/power density in the near future.

Rational Fabrication of Nitrogen and Sulfur Codoped Carbon Nanotubes/MoS2 for High‐Performance Lithium–Sulfur Batteries

“…In general, both physical confinement and chemical adsorption have been used to resolve the shuttle effect by capturing LiPSs within the cathode region . Recently, a unique conception of electrocatalysis has been introduced, in which some metals (Pt, Ni, Co) and metal sulfides or oxides (CoS 2 , WS 2 , MoS 2 , Nb 2 O 5 ) can expedite kinetic conversion and thus assist the shuttling of LiPSs . In general, during the discharge/charge process, the soluble long‐chain LiPSs can move between the cathode and anode; therefore, a fast conversion of sulfur species may be conducive to preventing the dissolution of polysulfides and restraining the polysulfide shuttle effect, to some extent .…”

“…[17] Recently,au nique conception of electrocatalysis has been introduced, in which somem etals (Pt, Ni, Co) and metal sulfides or oxides( CoS 2 ,W S 2 ,M oS 2 ,N b 2 O 5 )c an expedite kinetic conversion and thus assist the shuttling of LiPSs. [18][19][20][21][22] In general, during the discharge/charge process, the soluble long-chain LiPSs can move between the cathode and anode;t herefore, a Lithium-sulfur batteries are more promising anda ttractive than lithium-ion batteries owing to ah igher charge-storage capacity.H owever,t heir commercial applicationsa re hindered by an undesirable polysulfide shuttling effect during the cycling procedure. Herein, nitrogen and sulfur codoped carbon nanotubes intertwined with flower-like molybdenum disulfide (NSCNTs/MoS 2 )w eres ynthesized by using af easible hydrothermal method and used as effective lithium polysulfides (LiPSs) tamers.T he NSCNTs/MoS 2 had as trong hybrid structure with strong interfaciali nteractions for physicalc onfinement, chemical adsorption, and electrocatalytic conversion of intermediate LiPSs during the charge-discharge process.…”

The Role of Current Collector in Enabling the High Performance of Li/S Battery

“…[5][6][7][8][9] However, several issues, including capacity fading by cycling, low Coulombic efficiency and poor rate capability [10] hindered wide diffusion of the Li/S battery. These drawbacks, mainly due to poor conductivity of S, polysulfide shuttling, and loss of active material, [11] have been remarkably mitigated by moving to sulfur composite electrodes using a variety of carbons with different structures, textures and morphological characteristics, [12] and including polar species such as transition metal oxides. [13][14][15] Furthermore, electrolyte improvement [16][17][18][19] and, more recently, the use of an interlayer located between the cathode and the separator containing the electrolyte [20][21][22] have been proposed as suitable approaches for improving Li/S cell performances.…”

Intertwined Nitrogen‐Doped Carbon Nanotube Microsphere as Polysulfide Grappler for High‐Performance Lithium‐Sulfur Batteries

“…[11] To overthrow the aforementioned challenges, a significant number of works have been focused on the design of the cathode materials for LiÀ S batteries. [15,16] Among them, carbon materials play important roles in improving the electrical conductivity of the cathode and limit the waste of soluble polysulfide intermediates during cycling process and thus enhance the utilization and cyclability of active materials. [15,16] Among them, carbon materials play important roles in improving the electrical conductivity of the cathode and limit the waste of soluble polysulfide intermediates during cycling process and thus enhance the utilization and cyclability of active materials.…”