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Highlights The electrochemical principles/mechanism of Li–S batteries and origin of the shuttle effect have been discussed. The efficient strategies have been summarized to inhibit the shuttle effect. The recent advances of inhibition of shuttle effect in Li–S batteries for all components from anode to cathode.

A catalytic pseudo-8-electron redox reaction of sulfur is achieved by facilitating the disproportionation of high-order polysulfide ions in a Li-Sulfur battery. Electrochemically generated polysulfide ions (Sx2-, where 3

The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur (Li/S) cells. A comprehensive understanding of the shuttle-related sulfur speciation and diffusion process is vital for addressing this issue. Herein, we employed in situ/operando X-ray absorption spectroscopy (XAS) to trace the migration of polysulfides across the Li/S cells by precisely monitoring the sulfur chemical speciation at the cathodic electrolyte-separator and electrolyte-anode interfaces, respectively, in a real-time condition. After we adopted a shuttle-suppressing strategy by introducing an electrocatalytic layer of twinborn bismuth sulfide/bismuth oxide nanoclusters in a carbon matrix (BSOC), we found the Li/S cell showed greatly improved sulfur utilization and longer life span. The operando S K-edge XAS results revealed that the BSOC modification was bi-functional: trapping polysulfides and catalyzing conversion of sulfur species simultaneously. We elucidated that the polysulfide trapping-and-catalyzing effect of the BSOC electrocatalytic layer resulted in an effective lithium anode protection. Our results could offer potential stratagem for designing more advanced Li/S cells.

Aqueous zinc–iodine batteries are considered to be one of the most promising devices for future electrical energy storage due to their low cost, high safety, high theoretical specific capacity, and multivalent properties. However, the shuttle effect currently faced by zinc–iodine batteries causes the loss of cathode active material and corrosion of the zinc anodes, limiting the large-scale application of zinc–iodine batteries. In this paper, the electrochemical processes of iodine conversion and the zinc anode, as well as the induced mechanism of the shuttle effect, are introduced from the basic configuration of the aqueous zinc–iodine battery. Then, the inhibition strategy of the shuttle effect is summarized from four aspects: the design of cathode materials, electrolyte regulation, the modification of the separator, and anode protection. Finally, the current status of aqueous zinc–iodine batteries is analyzed and recommendations and perspectives are presented. This review is expected to deepen the understanding of aqueous zinc–iodide batteries and is expected to guide the design of high-performance aqueous zinc–iodide batteries.

Lithium-sulfur batteries (LiSBs) with high energy density still face challenges on sluggish conversion kinetics, severe shuttle effects of lithium polysulfides (LiPSs), and low blocking feature of ordinary separators to LiPSs. To tackle these, a novel double-layer strategy to functionalize separators is proposed, which consists of Co with atomically dispersed CoN 4 decorated on Ketjen black (Co/CoN 4 @KB) layer and an ultrathin 2D Ti 3 C 2 T x MXene layer. The theoretical calculations and experimental results jointly demonstrate metallic Co sites provide efficient adsorption and catalytic capability for long-chain LiPSs, while CoN 4 active sites facilitate the absorption of short-chain LiPSs and promote the conversion to Li 2 S. The stacking MXene layer serves as a microscopic barrier to further physically block and chemically anchor the leaked LiPSs from the pores and gaps of the Co/CoN 4 @KB layer, thus preserving LiPSs within efficient anchoring-conversion reaction interfaces to balance the accumulation of "dead S" and Li 2 S. Consequently, with an ultralight loading of Co/CoN 4 @KB-MXene, the LiSBs exhibit amazing electrochemical performance even under high sulfur loading and lean electrolyte, and the outperforming performance for lithium-selenium batteries (LiSeBs) can also be achieved. This work exploits a universal and effective strategy of a double-layer functionalized separator to regulate the equilibrium adsorption-catalytic interface, enabling high-energy and long-cycle LiSBs/LiSeBs., (© 2024 Wiley-VCH GmbH.)

Cationic lithium polysulfides (LiPSs) within ether‐based electrolytes are essential intermediates pivotal in instigating the shuttle effect. Suppressing the generation of cationic LiPSs is crucial for enhancing the performance of high‐energy‐density Li‐S batteries in practical applications. Herein, for the first time, it is demonstrated that cobalt phthalocyanine (CoPc) can significantly enhance the dissociation of LiPSs, leading to a decrease in cationic LiPSs species within the electrolyte. Employing NMR and in‐situ Raman spectroscopy, it is observed that CoPc interacts with sulfur anions within LiPSs, modifying the dissociation equilibrium of LiPSs in 1,2‐dimethoxyethane (DME)/1,3‐dioxolane (DOL) electrolyte. This CoPc‐mediated shift toward dissociation equilibrium reduces the concentration of cationic LiPSs, effectively suppressing the electromigration of LiPSs intermediates toward the Li anode during the charging process of Li‐S battery. As a result, the Li‐S battery enabled a high reversible areal capacity of 4.2 mAh cm−2 at a high sulfur loading of 5.0 mg cm−2 and a low electrolyte/sulfur (E/S) ratio of 3 µL mgs−1. This work affords a promising strategy for tackling the fundamental challenges regarding Li‐S batteries. [ABSTRACT FROM AUTHOR]