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Lithium‐sulfur (Li‐S) batteries have received tremendous academic and industrial attentions owing to their ultrahigh energy density. However, technical challenges including lithium dendrite formation, polysulfide shuttling and sluggish sulfur reaction kinetics limit their cycle life, rate capability and areal capacity, especially at practically high sulfur loadings. Here, coordination‐engineered graphite carbon nitrides is proposed to effectively address these challenges. On the anode a layer of novel N‐rich graphitic carbon nitride (g‐C3N5) is applied, in which tricoordinated N atoms display strong affinity to Li+, to guide lithium deposition and efficiently inhibit dendrite formation. Besides, a layer of defective g‐C3N5 carrying highly active bicoordinated N vacancies and cyano N atoms is applied on the cathode, which significantly adsorb polysulfides and catalyze the reversible conversion, as well as the nucleation and dissolution of Li2S thereby outcompeting polysulfide shuttling and raising kinetics at high sulfur loading. This coordination‐engineering strategy based on g‐C3N5 enables Li‐S batteries exhibiting high stability and low capacity‐fading‐rate (0.03% per cycle) in 400 cycles at the high current rate of 4 C, as well as Li‐S pouch cells showing a high areal capacity of 11.69 mAh cm−2 at a high sulfur loading of 9.02 mg cm−2, demonstrating the feasibility of Li‐S batteries in practical applications. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of complicated multiphase conversions and the severe shuttling effect of lithium polysulfides (LiPSs) significantly hinder the applications of Li‐S battery, which is one of the most promising candidates for the next‐generation energy storage system. Herein, a bifunctional electrocatalyst, indium phthalocyanine self‐assembled with carbon nanotubes (InPc@CNT) composite material, is proposed to promote the conversion kinetics of both reduction and oxidation processes, demonstrating a bidirectional catalytic effect on both nucleation and dissolution of Li2S species. The theoretical calculation shows that the unique electronic configuration of InPc@CNT is conducive to trapping soluble polysulfides in the reduction process, as well as the modulation of electron transfer dynamics also endows the dissolution of Li2S in the oxidation reaction, which will accelerate the effectiveness of catalytic conversion and facilitate sulfur utilization. Moreover, the InPc@CNT modified separator displays lower overpotential for polysulfide transformation, alleviating polarization of electrode during cycling. The integrated spectroscopy analysis, HRTEM, and electrochemical study reveal that the InPc@CNT acts as an efficient multifunctional catalytic center to satisfy the requirements of accelerating charging and discharging processes. Therefore, the Li–S battery with InPc@CNT‐modified separator obtains a discharge‐specific capacity of 1415 mAh g−1 at a high rate of 0.5 C. Additionally, the 2 Ah Li–S pouch cells deliver 315 Wh kg−1 and achieved 80% capacity retention after 50 cycles at 0.1 C with a high sulfur loading of 10 mg cm−2. Our study provides a practical method to introduce bifunctional electrocatalysts for boosting the electrochemical properties of Li–S batteries. [ABSTRACT FROM AUTHOR]

LiB alloy is promising lithium (Li) metal anode material because the continuous internal LiB fiber skeleton can effectively suppress Li dendrites and structural pulverization. However, the unvalued surface states limit the practical application of LiB alloy anodes. Herein, the study examined the influence of the different exposure manners of the internal LiB fiber skeleton owing to the various surface states of the LiB alloy anode on electrochemical performance and targetedly proposed a scalable friction coating strategy to construct a lithiated fumed silica (LFS) functional layer with abundant electrochemically active sites on the surface of the LiB alloy anode. The LFS significantly suppresses the inhomogeneous interfacial electrochemical behavior of the LiB alloy anode and enables the exposure of the internal LiB fiber skeleton in a homogeneously planar manner (LFS-LiB). Thus, a 0.5 Ah LFS-LiB||LiCoO 2 (LCO) pouch cell exhibits a discharge capacity retention rate of 80% after 388 cycles. Moreover, a 6.15 Ah LFS-LiB||S pouch cell with 409.3 Wh kg -1 exhibits a discharge capacity retention rate of 80% after 30 cycles. In conclusion, the study findings provide a new research perspective for Li alloy anodes., (© 2024 Wiley‐VCH GmbH.)