Interface Engineering Toward Expedited Li₂S Deposition in Lithium–Sulfur Batteries: A Critical Review

Abstract

Lithium–sulfur batteries (LSBs) with superior energy density are among the most promising candidates of next‐generation energy storage techniques. As the key step contributing to 75% of the overall capacity, Li2S deposition remains a formidable challenge for LSBs applications because of its sluggish kinetics. The severe kinetic issue originates from the huge interfacial impedances, indicative of the interface‐dominated nature of Li2S deposition. Accordingly, increasing efforts have been devoted to interface engineering for efficient Li2S deposition, which has attained inspiring success to date. However, a systematic overview and in‐depth understanding of this critical field are still absent. In this review, the principles of interface‐controlled Li2S precipitation are presented, clarifying the pivotal roles of electrolyte–substrate and electrolyte–Li2S interfaces in regulating Li2S depositing behavior. For the optimization of the electrolyte–substrate interface, efforts on the design of substrates including metal compounds, functionalized carbons, and organic compounds are systematically summarized. Regarding the regulation of electrolyte–Li2S interface, the progress of applying polysulfides catholytes, redox mediators, and high‐donicity/polarity electrolytes is overviewed in detail. Finally, the challenges and possible solutions aiming at optimizing Li2S deposition are given for further development of practical LSBs. This review would inspire more insightful works and, more importantly, may enlighten other electrochemical areas concerning heterogeneous deposition processes.

Challenges and Solutions for Lithium–Sulfur Batteries with Lean Electrolyte

“…Deterioration of electrolyte properties and formation of LiPS clusters further exacerbate the above problems. [ 78 ] Chen’ group [ 79 ] developed a porous and defective zeolite imidazole skeleton‐7 (ZIF‐7) by heat treatment, which had rich active edges with N defects. The exposed active edges ensure full contact with the active materials and realize efficient LiPS immobilization, and also show high catalytic activity towards Li 2 S nucleation and decomposition.…”

Impact of Morphological Dimensions in Carbon‐Based Interlayers on Lithium Metal Anode Stabilization

“…For instance, Li-O 2 batteries boast theoretical specific energies of around 3500 Wh kg −1 (non-aqueous electrolyte) and ≈3600 Wh kg −1 (aqueous electrolyte), whereas Li-S batteries hold a substantial specific energy of 2600 Wh kg −1 . [14][15][16] These batteries are capable of providing actual specific energies in the ballpark of 950 and 650 Wh kg −1 , correspondingly. Thus, rechargeable LMBs are seen as frontrunners for high-energydensity storage solutions, especially in the context of electric vehicles.…”

Advances in Selenium Sulfides Cathodes for Lithium/Selenium–Sulfur Batteries

“…Under the imperative of the Double Carbon Target to reduce greenhouse gas emissions and enhance responsiveness to climate change, there’s a growing need to shift focus away from fossil fuels toward high-performance energy storage. − Electrochemical energy storage stands out as a vital system among energy storage technologies due to its wide range of applications grounded in various redox reactions or Faraday effects. − Commercial lithium-ion batteries have achieved tremendous success in powering portable electronics but fall short of meeting the burgeoning energy demands, even at their full potential. − In the quest for advanced electric energy storage solutions, Li–S batteries have surfaced as an extremely viable option by virtue of their elevated theoretical energy density. − The sulfur cathode offers numerous advantages such as cost-effectiveness, abundance, nontoxicity, and high specific capacity. − However, its insulating nature and the challenges associated with polysulfides intermediates dissolution and volume expansion during the conversion of sulfur to Li 2 S result in limitations like low sulfur utilization, restricted rate performance, rapid capacity decay, and the notorious shuttle effect. − This shuttle effect triggers a parasitic reaction that causes a continuous loss of active substances, severely reducing the Coulombic efficiency and cycling stability. − Elemental selenium has surfaced as an alternative to sulfur because of its electrochemical properties and position in the periodic table with sulfur. Although Li–Se batteries have a marginally lower theoretical weight-based energy density compared to Li–S variants, they make up for it with an impressive theoretical volume-based energy density of 3254 mAh cm –3 , attributed to their high density (4.8 g cm –3 ). − A distinguishing feature of selenium is its semiconductive characteristics, which offer an electronic conductivity that is approximately 20 orders of magnitude greater than sulfur, along with a high discharge voltage. − These attributes contribute to greater lithium activity, better active materials utilization, superior rate performance, and increased overall energy density. − Nonetheless, the limited availability and consequent high cost of selenium on Earth, along with persistent challenges related to the shuttle effect and capa...…”