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Despite a high theoretical capacity, the practical application of lithium-sulfur batteries has been primarily limited by the migration of long-chained polysulfide species during the charge/discharge processes. One effective approach to address the issues is to design a functional separator or interlayer. Here, we prepared a modified separator with an ultrathin layer of titanium carbide (TiC) using radio-frequency sputtering on a commercial Celgard polypropylene membrane. The 240-nm TiC coating layer can enhance the interfacial properties of Celgard separators in porosity, wettability, roughness, etc. Hence, via experimental and theoretical investigation, we discovered that TiC can efficiently adsorb polysulfides and boost charge transfer via strong covalent C–S bonds. Using a TiC-modified separator can impede the shuttle effect and improve the kinetics of sulfur conversion reactions. Thus, the Li–S batteries with TiC separator deliver excellent electrochemical performances with a good rate capability (717 mAh g−1 at 7.0C) and an ultra-low decay rate of 0.058 % per cycle over 800 cycles at a C-rate of 2.0C. Furthermore, a high areal capacity of 4.3 mAh cm−2 was achieved with a high mass-loading of sulfur cathode up to 7.0 mg cm−2. [Display omitted] • Titanium carbide (TiC)-modified separator was used for lithium-sulfur batteries. • TiC adsorbs and covalently binds with long-chained polysulfide species via C–S bonds. • Li–S battery with TiC-separator achieves a high capacity decay rate of 0.058% for 800 cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] The sluggish redox reaction kinetics and "shuttle effect" of lithium polysulfides (LPSs) impede the advancement of high-performance lithium-sulfur batteries (LSBs). Transition metal phosphides exhibit distinctive polarity, metallic properties, and tunable electron configuration, thereby demonstrating enhanced adsorption and electrocatalytic capabilities towards LPSs. Consequently, they are regarded as exceptional sulfur hosts for LSBs. Moreover, the introduction of a heterogeneous structure can enhance reaction kinetics and expedite the transport of electrons/ions. In this study, a composite of hollow CoP-FeP cubes with heterostructure modified carbon nanotube (CoFeP-CNTs) was fabricated and utilized as sulfur host in advanced LSBs. The presence of carbon nanotubes (CNTs) facilitates enhanced electron and Li+ transport. Meanwhile, the active sites within the heterogeneous interface of CoP-FeP suppress the "shuttle effect" and enhance the conversion kinetics of LPSs. Therefore, the CoFeP-CNTs/S electrode exhibited exceptional cycling stability and demonstrated a capacity attenuation of merely 0.051 % per cycle over 600 cycles at 1C. This study presents a highly effective tactic for synthesizing dual-acting transition metal phosphides with heterostructure, which will play a pivotal role in advancing the development of efficient LSBs. [ABSTRACT FROM AUTHOR]

The seemingly advantageous features of carbon‐based materials, such as large pore volume and lightweight structure, could actually lead to low tap density for the sulfur cathode and excessive electrolyte consumption, potentially significantly decreasing the energy density of lithium–sulfur battery. Recently, non‐carbon‐based materials composed of inorganic matter have emerged as promising candidates for creating dense sulfur cathodes and reducing electrolyte intake. Additionally, inorganic matter exhibits strong interactions with lithium polysulfides, which can address the intrinsic problems of the severe shuttling effect and poor reaction kinetics. In this review, we first discuss the relationship between the tap density of the sulfur cathode and the energy density of lithium–sulfur battery. Subsequently, we systematically summarize recent advances in non‐carbon‐based materials as sulfur hosts. Finally, we propose future research directions and perspectives for sulfur host materials to inspire the realization of practical lithium–sulfur battery with high energy density. [ABSTRACT FROM AUTHOR]

Garnet-type Ta-doped Li 7 La 3 Zr 2 O 12 (LLZO) lithium-ion-conducting ceramic electrolytes has become the promising and critical candidate for developing the high-energy-density all-solid-state lithium batteries, due to the satisfied Li+ conductivity, stability against metallic lithium anode, and the feasible preparation under ambient air. Here, to further increase the lithium-ion conductivity of LLZO comparable to that of the commercial organic liquid electrolytes, lithium chloride (LiCl) is effectively introduced to synthesize the garnet-type ceramic electrolytes with the nominal composition (Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12) 1-x –(LiCl) x (x = 0, 5mol%, 10mol%, 15mol%, 20mol%, and 25mol%) via high-temperature calcination process. The cubic structure with highly conductive performance is confirmed from X-ray diffraction measurement as well as Raman spectra analysis. Structural information is observed according to field emission scanning electron microscope equipped with energy dispersive spectrometer and density measurements. Among above investigated ceramic compositions, the prepared (Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12) 0.85 –(LiCl) 0.15 ceramic electrolyte sheet sintered at 1200 °C for 12h presents the room-temperature Li-ion conductivity of 1.22 × 10−3 S·cm−1 by alternating current (AC) impedance analysis along with the corresponding activation energy of 0.262eV through Arrhenius equation calculation. The electronic conductivity measurements are also done by direct-current polarization to confirm the ionic nature for all investigated ceramics. Furthermore, the Li|(Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12) 0.85 –(LiCl) 0.15 |Li symmetric batteries can possess the small interfacial resistance of 92.3 Ω cm2 and stably run for 1000 h at 0.1 mA cm−2 without a short circuit at room temperature. The hybridized lithium-sulfur battery with (Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12) 0.85 –(LiCl) 0.15 electrolyte delivered excellent initial room-temperature discharge capacity of 1204mAh·g−1 and 1152 mAh·g−1 under the current density of 0.1C and 0.2C respectively, large coulombic efficiency, and great cycling stability. Moreover, the lithium-sulfur batteries also can show excellent cycling performances under different current densities and a good capacity recoverability. The above investigation results suggest that the low-melting-point LiCl incorporation in Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12 electrolyte is an effective measurement to synthesize the cubic and dense Li-stuff garnet ceramic sheets for the high-performance rechargeable next-generation solid-state batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mo 2 C-Co heterostructure embedded in carbon nanosheets is designed to modify both interlayer and cathode for Li-S battery. • Mo 2 C-Co has abundant adsorption sites to adsorb polysulfides and accelerate Li+ migration. • Mo 2 C-Co enables rapid uniform deposition and complete oxidation of Li 2 S. • Superior Li-S battery performance is achieved under high rate, high sulfur loading or low temperature. The practical applications of lithium sulfur batteries (LSBs) are hindered by notorious shuttle effect and sluggish conversion kinetics of intermediate polysulfides. Herein, Mo 2 C-Co heterogeneous particles decorated two-dimensional (2D) carbon nanosheets grown on hollow carbon microtubes (CCC@MCC) are synthesized. Three-dimensional (3D) carbon framework with Mo 2 C-Co heterogeneous particles combines the conductivity, adsorption and catalysis, effectively trapping and accelerating the conversion of polysulfides. As evidenced experimentally, the hetero-structured Mo 2 C-Co with high Li+ diffusion coefficient enables uniform precipitation and complete oxidation of Li 2 S. Meanwhile, CCC@MCC is found to have multiple application possibilities for lithium-sulfur batteries. As an interlayer, the cells deliver an excellent capacity of 881.1 mAh/g at 2C and still retain 438.2 mAh/g after 500 cycles under the low temperature of 0 ℃. As a sulfur carrier, the cell with a sulfur loading of 7.0 mg cm−2 exhibits a high area capacity of 5.3 mAh cm−2. This work provides an effective strategy to prepare heterostructured material and imaginatively exploit the application potential of it. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are considered as potential candidates for future‐oriented energy storage systems. However, their practical deployment is hampered by the shuttle effect and the sluggish reaction kinetics of lithium polysulfides (LiPSs). A key strategy to mitigate these challenges is to develop efficient heterojunction catalysts to enhance reaction kinetics and suppress the shuttle effect. In this study, a NiS2‐CoS2 heterojunction is introduced to address these challenges with density functional theory (DFT) calculations employed to determine the optimal combination from 5  ×  5 crystal plane configurations. The identified NiS2(210)‐CoS2(200) combination demonstrates excellent anchoring effects and catalytic properties for LiPSs, significantly enhancing rate performance (839.9 mAh g−1 at 2 C and 730.8 mAh g−1 at 3 C) and cycling stability. Furthermore, in situ Raman and X‐ray diffraction (XRD) analyses reveal that the NiS2‐CoS2 heterojunction rapidly catalyzes the conversion of LiPSs, reducing their migration toward the lithium anode and thereby suppressing the shuttle effect. The design strategy for transition metal sulfide heterojunctions offers an efficient approach to accelerating polysulfide conversion kinetics, effectively addressing the limitations of Li–S batteries. [ABSTRACT FROM AUTHOR]

The uncontrolled polysulfide shuttling and lithium dendrite growth greatly impede the practical implementation of Li–S batteries. These issues can be alleviated by constructing an artificial layer that immobilizes soluble polysulfides and regulates Li+ flux. Here, a layer‐expanded lithium montmorillonite is fabricated through molecular intercalation to serve as a dual regulator for Li–S batteries. The lithiophilic montmorillonite, with its ordered and expanded Li+ diffusion channels, exhibits a high transference number, and promotes homogeneous Li deposition. Additionally, its moderate adsorption of polysulfides, combined with favorable Li diffusion behavior, enhanced the redox kinetics of sulfur species. This unique structure enables a prolonged lifespan of 1000 cycles at 0.5C with a low capacity decay of 0.04% per cycle for practical Li–S batteries. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) present diverse building blocks for high‐performance materials across industries, yet their crystallization mechanisms remain incompletely understood due to gaps in nucleation and growth knowledge. In this study, MOF structural evolution is probed using in situ liquid phase transmission electron microscopy (TEM) and cryo‐TEM, unveiling a blend of classical and nonclassical pathways involving liquid–liquid phase separation, particle attachment–coalescence, and surface layer deposition. Additionally, ultrafast high‐temperature sintering (UHS) is employed to dope ultrasmall Cobalt nanoparticles (Co NPs) uniformly within nitrogen‐doped hard carbon nanocages confirmed by 3D electron tomography. Lithium–sulfur battery tests demonstrate the nanocage‐Co NP structure's exceptional capacity and cycling stability, attributed to Co NP catalytic effects due to its small size, uniform dispersion, and nanocage confinement. The findings propose a holistic framework for MOF crystallization understanding and Co NP tunability through ultrafast sintering, promising advancements in materials science and informing future MOF synthesis strategies and applications. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are considered as a viable technology offering energy‐dense electrochemical energy storage systems. However, the inherently slow reaction kinetics manifested in the slow charge and discharge characteristics constrain their real‐world applications. Here, it is reported that polyiodide species held within a complex polar network of polyvinylpyrrolidone (PVP) accelerate the rate‐limiting solid‐liquid phase transitions both in the reduction and oxidation steps during battery cycling. Density functional theory calculations support a mechanism in which a combination of enhanced binding of polysulfides and additional energy states in the PVP‐iodine‐polysulfide complexes accelerates the reaction pathways mediated by inter‐valance polyiodide reactions within the working voltage of Li–S batteries. These studies show that PVP‐iodine (PVP‐I) complexes enhance the rate capability of cells with practical sulfur loadings delivering a high areal capacity of ≈7 mAh cm−2 at the practical 0.5C rate. This advantage is demonstrated in one of the highest‐rate pouches reported in Li–S literature, attaining energy densities of 215 and 156 Wh kg at 0.1C and 0.3C, respectively. The results demonstrate a subtle but powerful shift in the design of molecular binder systems, which have functional roles above and beyond the role of simply holding the active materials together. [ABSTRACT FROM AUTHOR]

[Display omitted] Lithium-sulfur batteries (LSBs) hold promise as the next-generation lithium-ion batteries (LIBs) due to their ultra-high theoretical capacity and remarkable cost-efficiency. However, these batteries suffer from the serious shuttle effect, challenging their practical application. To address this challenge, we have developed a unique interlayer (HCON@CNWF) composed of hollow cerium oxide nanorods (CeO 2) anchored to carbonized non-woven viscose fabric (CNWF), utilizing a straightforward template method. The prepared interlayer features a three-dimensional (3D) conductive network that serves as a protective barrier and enhances electron/ion transport. Additionally, the CeO 2 component effectively chemisorbs and catalytically transforms lithium polysulfides (LiPSs), offering robust chemisorption and activation sites. Moreover, the unique porous structure of the HCON@CNWF not only physically adsorbs LiPSs but also provides ample space for sulfur's volume expansion, thus mitigating the shuttle effect and safeguarding the electrode against damage. These advantages collectively contribute to the battery's outstanding electrochemical performance, notably in retaining a reversible capacity of 80.82 % (792 ± 5.60 mAh g−1) of the initial value after 200 charge/discharge cycles at 0.5C. In addition, the battery with HCON@CNWF interlayer has excellent electrochemical performance at high sulfur loading (4 mg cm−2) and low liquid/sulfur ratio (7.5 µL mg−1). This study, thus, offers a novel approach to designing advanced interlayers that can enhance the performance of LSBs. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries, as one of the most promising "post‐Li‐ion" energy storage devices, encounter several intrinsic challenges: polysulfide dissolution and shuttle effect, poor sulfur utilization, lithiation‐induced sulfur expansion, and lithium dendritic growth. These challenges must be resolved, and the associated mechanisms must be completely understood before the practical applications of Li–S batteries. Despite significant progress in enhancing battery capacities, experimental studies on the working mechanisms of Li–S batteries remain challenging. Alternatively, computational methods are proven useful for understanding Li–S electrochemistry and designing high‐performance Li–S batteries. This review presents recent advances in computational methods (density functional theory, molecular dynamics simulations, and finite element analysis) for Li–S batteries, compares their advantages, and summarizes their favorable applications in addressing the challenges of Li–S batteries. Computational methods should find more applications in the development of Li–S batteries. [ABSTRACT FROM AUTHOR]

To address the inherent limitations of conventional carbon nanotubes (CNTs), such as their tendency to agglomerate and scarcity of catalytic sites, the development of branched carbon nanotubes (BCNTs) with a unique hierarchical structure has emerged as a promising solution. Herein, gram scale quantities of densely branched and structurally consistent Ni−Fe decorated branched CNTs (Ni−Fe@BCNT) have been prepared. This uniform and densely branched architecture ensures excellent dispersibility and superior electrical conductivity. Additionally, each branched tip is equipped with Ni−Fe particles, thereby providing numerous catalytic sites which endow them with exceptional catalytic activity for the conversion of polysulfides. The polypropylene (PP) separator modified with Ni−Fe@BCNT interlayer is fabricated as a multifunctional barrier for Li–S batteries. The experimental results demonstrate that Ni−Fe@BCNT interlayer can effectively suppress the shuttle effect of polysulfides and enhance their redox kinetics. The outstanding catalytic ability of Ni−Fe@BCNT interlayer enables batteries with high specific capacities, outstanding rate performance, and remarkable cycling stability. This approach proposed in this work paves a new path for synthesizing BCNTs and shows great potential for scaling up the production of BCNTs to address more demanding applications. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) are known as high energy density, but their performance deteriorates sharply under high/low‐temperature surroundings, due to the sluggish kinetics of sulfur redox conversion and Li+ transport. Herein, a catalytic strategy of phase reconstruction with abundant “electron‐Li+” reservoirs has been proposed to simultaneously regulate electron and Li+ exchange. As a demo, the 1T‐phase lithiation molybdenum disulfide grown on hollow carbon nitride (1T‐LixMoS2/HC3N4) is achieved via in situ electrochemical modulation, where the 1T‐LixMoS2 serves as an auxiliary “Li+ source” for facilitating Li+ transport and the HC3N4 acts as an electron donor for electronic supplier. From the theoretical calculations, experimental and post‐modern analyses, the relationship between the catalytic behaviors and mechanism of “electron‐Li+” reservoirs in accelerating the rate‐determining kinetics of sulfur species are deeply understood. Consequently, the cells with 1T‐LixMoS2/HC3N4/PP functional separator demonstrate excellent long‐term electrochemical performance and stabilize the areal capacity of 6 mAh cm−2 under 5.0 mg cm−2. Even exposed to robust surroundings from high (60 °C) to low (0 °C) temperatures, the optimized cells exhibit high‐capacity retention of 76.2% and 90.4% after 100 cycles, respectively, pointing out the potential application of catalysts with phase reconstruction‐assisted “electron‐Li+” reservoirs in LSBs. [ABSTRACT FROM AUTHOR]

The separators used in lithium‐sulfur (Li–S) batteries play a crucial role in their cycling performance and safety. Current commercial separators lack the ability to efficiently regulate polysulfide shuttling and are prone to thermal runaway at high temperatures. Recent studies have shown that multifunctional separators can boost the electrochemical performance and safety of Li–S batteries. Metal–organic frameworks (MOFs) have emerged as promising materials for modifying separators due to their large specific surface areas and highly ordered tunable nanopores. Herein, this review focuses on the advancements in developing MOFs, their derivatives, and MOFs‐based composites as separator coatings to address the shortcomings of Li–S batteries. The mechanisms behind these modified separators, designed to inhibit lithium polysulfide shuttling and lithium dendrite growth, are discussed, emphasizing the relationship between the structure and electrochemical performance. The impact of these modified separator coatings on battery safety is also explored, aiming to design suitable composite films for high‐safety Li–S batteries. Furthermore, future perspectives are outlined to guide practical applications and overcome the remaining challenges associated with MOFs‐modified separators. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur (Li‐S) batteries, with their high theoretical energy density and cost‐effectiveness, have become one of the most promising next‐generation energy storage devices. However, they still face challenges such as the “shuttle effect” caused by the dissolution of polysulfide intermediates and the slow sulfur conversion kinetics. In this study, based on the Co7Fe3 alloy catalyst, additional Co metal is introduced to form a Co7Fe3Co catalyst with a heterostructure through a simple heat treatment process. This catalyst is incorporated into Ketjenblack (KB) to form a sulfur‐infused cathode material (designated as S/KB/Co7Fe3Co). Li‐S batteries using S/KB/Co7Fe3Co as the cathode demonstrate outstanding electrochemical performance, maintaining a reversible specific capacity of over 500 mAh g−1 after 1000 cycles at a current density of 1 C, with a capacity decay rate of 0.046% per cycle. DFT theoretical calculations and experimental results both reveal that the introduction of additional Co effectively regulates the d‐band center of the material, enhancing the adsorption of polysulfide intermediates by Co7Fe3Co and promoting bidirectional catalytic sulfur conversion. This work highlights the importance of the simple construction of heterostructured catalytic materials and their role in improving the performance of Li‐S batteries. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries have hindered industrialization due to their inherent defects. In this study, MXene and CNT composite Ni12P5 were used as cathode materials for lithium-sulfur batteries. MXene is known to have high specific surface area, while the CNT composite Ni12P5 has excellent electrical conductivity. The results show that MXene-CNT@ Ni12P5 composite can significantly improve the performance of lithium-sulfur batteries. The composite helps to mitigate the volume expansion and shuttle effect of the sulfur cathode, thereby improving the diffusion efficiency and cycling stability of the battery. In addition, the incorporation of the composite material enhances the electrical conductivity of the battery, reduces the secondary reaction with the electrolyte, and mitigates the deposition of polysulfides during lithium-ion charging and discharging, thereby further improving the lithium-ion diffusion efficiency. Therefore, this study presents a novel and convenient method to enhance the cathode material of lithium-sulfur batteries, which offers a broad prospect for its application in this field. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) battery is attracting increasing interest for its potential in low‐cost high‐density energy storage. However, it has been a persistent challenge to simultaneously realize high energy density and long cycle life. Herein, we report a synergistic strategy to exploit a unique nitrogen‐doped three‐dimensional graphene aerogel as both the lithium anode host to ensure homogeneous lithium plating/stripping and mitigate lithium dendrite formation and the sulfur cathode host to facilitate efficient sulfur redox chemistry and combat undesirable polysulfide shuttling effect, realizing Li–S battery simultaneously with ultrahigh energy density and long cycle life. The as‐demonstrated polysulfide‐based device delivers a high areal capacity of 7.5 mAh/cm2 (corresponds to 787 Wh/L) and an ultralow capacity fading of 0.025% per cycle over 1000 cycles at a high current density of 8.6 mA/cm2. Our findings suggest a novel strategy to scale up the superior electrochemical property of every microscopic unit to a macroscopic‐level performance that enables simultaneously high areal energy density and long cycling stability that are critical for practical Li–S batteries. [ABSTRACT FROM AUTHOR]

Construction of advanced carbon material is critical for the development of high-performance lithium–sulfur batteries. In this work, we report Rhizopus hyphae biomass carbon (RHBC) as a host material for the sulfur cathode of lithium–sulfur batteries. The porous structure of the RHBC is optimized through hydrothermal activation using KOH solution. The introduction of RHBC into the cathode not only enhances the electronic conductivity of the sulfur cathode, but also substantially improves the capacity of the active materials. Additionally, the RHBC can effectively relieve the volume expansion problem of the sulfur conversion reaction and maintain structural stability, leading to improved lifetime and capacity. Accordingly, the KOH-activated RHBC/S cathode presents initial discharge specific capacity of 748 mAh/g at current density of 0.1 C. Furthermore, the porous structure facilitates rapid transport of electrons and ions, thereby enabling good high-rate performance. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries have not been widely commercialized due to issues with poor conductivity of the active material and the shuttle effect, both of which are effectively addressed in this study. The porous carbon CoNi-NC, derived from high-temperature carbonization of the cobalt–nickel metal–organic framework CoNi-ZIF, was utilized as the carbon substrate. It exhibits excellent specific surface area and a well-developed pore structure, thereby optimizing the conductivity and sulfur-loading capacity of the material. The incorporation of polar Bi2S3 effectively adsorbs polysulfides, retards the shuttle effect, and enhances the reaction kinetics of lithium-sulfur batteries. Electrochemical tests revealed that the CoNi-NC@Bi2S3 electrode achieved a specific discharge capacity of 1107 mAh/g at 0.1 C rate, demonstrating excellent rate capability. Moreover, the cathode material maintained a specific discharge capacity of 796.5 mAh/g after 200 cycles at 0.2 C, indicating robust cycling stability. [ABSTRACT FROM AUTHOR]

Developing efficient and durable single‐atom catalysts is vitally important for the sulfur redox reaction (SROR) in Li−S battery, while it remains enormous challenging. Herein, undercoordinated Ni−N3 moieties anchored on N,S‐codoped porous carbon (Ni−NSC) is obtained to enhance the SROR. The experiments and theoretical calculations indicate that the symmetry‐breaking charge transfer in Ni single‐atom catalyst originates from tuning effect of sulfur atoms mediated Ni−N3 moieties, which can both facilitate the chemical adsorption by formation of N−Ni⋅⋅⋅Sn2−, and achieve a rapid redox conversion of polysulfides because of the enhanced electron transfer. As results, the Ni−NSC based Li−S battery delivers a very high initial reversible capacity (1025 mAh g−1 at 1 C), as well as outstanding cycling‐stability for 2400 cycles at 2 C and 3 C, respectively. Noteworthy, the areal capacity can reach 7.8 mAh cm−2 at 0.05 C and a retention capacity of 4.7 mAh cm−2 after 100 cycles at 0.2 C for Ni−NSC based Li−S battery with sulfur loading of 5.88 mg cm−2. This work provides profound insight for rational optimizing microscopic electronic density of active site to promoting SROR in metal‐sulfur batteries. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) have become one of the most powerful candidates for next‐generation battery technologies due to their high theoretical energy density and low cost. However, the notorious shuttle effect of soluble lithium polysulfides (LiPSs) and sluggish conversion reaction kinetics cause low sulfur utilization and inferior cycle life. Rational catalyst design on hierarchical pore structures and composition optimization is highly desired to realize synergetic enrichment, accommodation, and catalytic redox capacity of sulfur species. In this consideration, the hollow and porous N‐doped carbon framework is prepared, in which Co nanoparticles (NPs) are evenly embedded (denoted as Co‐HMCF) to modulate electron cloud density of carbons. Electrochemical tests and density functional theory (DFT) calculations demonstrate that Co‐HMCF could simultaneously deliver superior catalytic activity in accelerating LiPSs conversion as well as Li2S nucleation/decomposition to improve overall sulfur redox kinetics. Consequently, the Co‐HMCF interlayer significantly improves the battery performance, including high discharge capacity output (1538 mAh g−1 at 0.2 C), stable long‐term cycle (0.047% capacity decay per cycle for 800 cycles at 1.0 C), and exceptional rate capacity (582 mAh g−1 at 5.0 C). [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) have attracted increasing attention in the past decades due to their great potential to the next‐generation high‐energy‐density storage systems. As important as electrodes, electrolytes that could strongly determine battery performance via component regulation have left big difficulties in clarifying their complex interactions caused by multicomponent as well as the intricate formation mechanism of passivation layers at the electrolyte‐electrode interfaces. Fortunately, machine learning (ML), which is time‐saving and highly efficient, has played an irreplaceable role in accelerating discovery, design, and optimization of novel electrochemical energy storage materials. In this concept, we summarize the complex issues present in multicomponent electrolytes and focus on optimization of electrolyte formulations based on ML in order to provide an outlook on the recent development and perspectives on LSBs from the viewpoint of high‐performance electrolytes. [ABSTRACT FROM AUTHOR]

The cycling lifespan of high‐energy‐density lithium–sulfur (Li–S) batteries is dominantly limited by the rapid failure of Li metal anodes. Herein, the evolution of Li metal anode along cycling is systematically investigated in Li–S batteries to clarify the Li plating and stripping behaviors, the generation and accumulation of inactive Li, and the failure mechanism of Li metal anodes. Concretely, plated Li strips preferentially than bulk Li to leave massive stripping Li shells during initial discharge, and the stripping Li shells are refilled by plated Li during the subsequent charge to generate thick Li dendrites. During the following cycles, inactive Li generates and accumulates on top of bulk Li due to solid electrolyte interphase formation and incomplete removal of plated Li. Eventually, the accumulation of inactive Li hinders the diffusion of Li ions through the inactive Li layer to induce cell polarization at the end of the second discharge plateau and rapid decay of discharge capacity. This work elucidates the detailed evolution mechanism of Li metal anode along cycling in working Li–S batteries and highlights the reactivation of inactive Li as an effective strategy to prolong the cycling lifespan of Li–S batteries. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium‐sulfur batteries (ASSLSBs) are garnering significant interest due to their high energy density and safety. Nevertheless, the interfacial instability, particularly with sulfide‐based solid electrolytes, poses a formidable challenge to their widespread application. Herein, to adjust the p‐band center of the tetrahedron in Li6PS5Cl is proposed to alleviate undesirable reactions at anode and cathode interfaces via facile Sb/O co‐doping. The incorporation of Sb into Li6PS5Cl forms an SbS4 tetrahedron, resulting in the downward shift of the S‐p band center. This benefits the acquisition of electrons from Li to in situ forming stable LixSbySz interphase at the Li/LPSC‐SbO interface. The Li symmetric cell endows a high stability for over 4000 h. Moreover, the lower p‐band center of the S‐p band also strengthens the interaction of the SbS4 tetrahedron with surrounding Li atoms, impeding charge transfer to S8 and mitigating interfacial side reactions on the sulfur cathode. Additionally, O doping enhances the air stability of the electrolyte. The ASSLSBs with LPSC‐SbO achieve a high specific capacity of 932.6 mAh g−1 at 0.1 C with 83.7% capacity retention over 150 cycles. Furthermore, the practical all‐solid‐state pouch cell demonstrates stable cycling performance and anticipated safety. This work provides insights into constructing stable dual solid–solid interfaces for sulfide‐based room‐temperature high‐performance ASSLSBs. [ABSTRACT FROM AUTHOR]

Microstructure and property of sulfur/carbon black composites prepared by ball milling were studied. Sulfur/carbon black composites were obtained by melting the mixture of sulfur and carbon black in 155 °C and dispersing evenly in carbon black after hydrothermal reaction. Thus, its conductive properties were improved. Moreover, microstructure and property of honeycomb sulfur/carbon black/ MoS2 prepared by hydrothermal method as a cathode material for lithium-sulfur batteries were studied. The initial discharge specific capacity of the material at 0.2 A/g current density is 838.495 mA·h/g, and the 55.14% after 100 weeks of cycling. It is indicated that MoS2 can not only combine with polysulfides through electrostatic action or the action of chemical bonds, but also honeycomb porous structure. MoS2 can fix polysulfides groups and prevent their shuttle. Therefore, the cycling performance of the battery is effectively improved. [ABSTRACT FROM AUTHOR]

[Display omitted] Lithium–sulfur batteries (LSBs) have been sought after by researchers owing to their high energy density; however, the inevitable capacity decay and slow reaction kinetics have hindered their advancement. Here, we prepare a Prussian blue analog, Co 3 [ Co (CN) 6 ] 2 and synthesize carbon nanofibers/S vacancy CoS 2−x (CNFs/CoS 2−x) as electrocatalysts for separator coating via electrospinning, carbonization, sulfurization, and hydrogen reduction. CNFs/CoS 2−x exhibits excellent electrocatalytic activity, wherein S vacancies induce the partial oxidation of Co2+ to Co3+ in CoS 2 and CNFs provide long-range electron transport pathways. Various electrochemical tests, such as Tafel, ion diffusion coefficient, Li 2 S precipitation, and Li 2 S 6 symmetric cells, further confirm the enhanced electrocatalytic activity. The LSBs with CNFs/CoS 2−x modified separator delivers an initial discharge capacity of 1056.7 mAh g−1 at 0.2C, maintaining 840.8 mAh g−1 after 100 cycles at 0.2C. When S loading is increased to 4.42 mg cm−2, the battery retains a discharge capacity of 687.9 mAh g−1 (3.04 mAh cm−2) after 70 cycles at 0.1C. Our work can provide a reference for synthesizing anion-vacancy materials and designing anion-vacancy electrocatalytic composites for LSBs. [ABSTRACT FROM AUTHOR]

Highlights By introducing fluorine modulation into MXene, a new MXene-derived material TiOF/Ti3C2 was successfully synthesized with a distinctive three-dimensional structure and a tailored F distribution. In situ characterizations and electrochemical analyses demonstrate that TiOF/Ti3C2 catalysts effectively coupled the multiphase sulfur species conversion processes. The investigations reveal that the theoretical basis of the fluorine catalysis in Li–S batteries originated from Lewis acid–base mechanisms and charge compensation mechanisms.

Practical application of lithium–sulfur (Li–S) batteries is severely impeded by the random shuttling of soluble lithium polysulfides (LiPSs), sluggish sulfur redox kinetics, and uncontrollable growth of lithium dendrites, particularly under high sulfur loading and lean electrolyte conditions. Here, nitrogen‐doped bronze‐phase TiO2(B) nanosheets with oxygen vacancies (OVs) grown in situ on MXenes layers (N‐TiO2−x(B)‐MXenes) as multifunctional interlayers are designed. The N‐TiO2−x(B)‐MXenes show reduced bandgap of 1.10 eV and high LiPSs adsorption‐conversion‐nucleation‐decomposition efficiency, leading to remarkably enhanced sulfur redox kinetics. Moreover, they also have lithiophilic nature that can effectively suppress dendrites growth. The cell based on the N‐TiO2−x(B)‐MXenes interlayer under sulfur loading of 2.5 mg cm−2 delivers superior cycling performance with a high specific capacity of 690.7 mAh g−1 over 600 cycles at 1.0 C. It still has a notable areal capacity of 6.15 mAh cm−2 after 50 cycles even under a high sulfur loading of 7.2 mg cm−2 and a low electrolyte‐to‐sulfur (E/S) ratio of 6.4 µL mg−1. The Li‐symmetrical battery with the N‐TiO2−x(B)‐MXenes interlayer showcases a low over‐potential fluctuation with 21.0 mV throughout continuous lithium plating/stripping for 1000 h. This work offers valuable insights into the manipulation of defects and heterostructures to achieve high‐energy Li–S batteries. [ABSTRACT FROM AUTHOR]

Severe shuttle effect of soluble polysulfides and sluggish redox kinetics have been thought of as the critical issues hindering the extensive applications of lithium‐sulfur batteries (LSBs). Herein, one‐dimensional boron nitride (1D BN) fibers with abundant pores and sufficient N‐vacancy defects were synthesized using a thermal crystallization following a pre‐condensation step. The 1D structure of BN facilitates unblocked ions diffusion pathways during charge/discharge cycles. The embedded pores within the polar BN strengthen the immobilization of polysulfides via both physical confinement and chemical interaction. Moreover, the highly exposed active surface area and intentionally created N‐vacancy sites substantially promote reaction kinetics by lowering the energy barriers of the rate‐limiting steps. After incorporating with conductive carbon networks and elemental S, the as‐prepared S/Nv‐BN@CBC cathode of LSBs deliver an initial discharge capacity of up to 1347 mAh g−1 at 200 mA g−1, while maintaining a low decay rate of 0.03 % per cycle over 1000 cycles at 1600 mA g−1. This work offers an effective strategy to mitigate the shuttle effect and highlights the significant potential of defect‐engineered BN in accelerating the reaction kinetics of LSBs. [ABSTRACT FROM AUTHOR]

The "shuttle effect" issue severely hinders the practical application of lithium–sulfur (Li–S) batteries, which is primarily caused by the significant accumulation of lithium polysulfides in the electrolyte. Designing effective catalysts is highly desired for enhancing polysulfide conversion to address the above issue. Here, the one‐step flash‐Joule‐heating route is employed to synthesize a W‐W2C heterostructure on the graphene substrate (W‐W2C/G) as a catalytic interlayer for this purpose. Theoretical calculations reveal that the work function difference between W (5.08 eV) and W2C (6.31 eV) induces an internal electric field at the heterostructure interface, accelerating the movement of electrons and ions, thus promoting the sulfur reduction reaction (SRR) process. The high catalytic activity is also confirmed by the reduced activation energy and suppressed polysulfide shuttling by in situ Raman analyses. With the W‐W2C/G interlayer, the Li–S batteries exhibit an outstanding rate performance (665 mAh g−1 at 5.0 C) and cycle steadily with a low decay rate of 0.06% over 1000 cycles at a high rate of 3.0 C. Moreover, a high areal capacity of 10.9 mAh cm−2 (1381.4 mAh g−1) is obtained with a high area sulfur loading of 7.9 mg cm−2 but a low electrolyte/sulfur ratio of 9.0 µL mg−1. [ABSTRACT FROM AUTHOR]

Many challenges in lithium‐sulfur (Li–S) batteries are associated with the radical change in lithium polysulfide (LPS) solubility during cycling, but chemical approaches to address such inconsistency are still lacking. Here, the use of a strong Lewis acidic fluorinated organoboron, tri(2,2,2‐trifluoroethyl) borate (TFEB), is reported as a multi‐functional mediator to simultaneously overcome multiple technical barriers in practical Li–S batteries. TFEB acts as an anion acceptor and forms strong molecular complexes with Lewis basic LPS. The TFEB‐LPS complexes have consistent solubility across the full polysulfide spectrum and deliver several times improved better redox kinetics, unlocking a true redox catalytic mechanism that covers the majority of redox events in thick sulfur cathodes. As a result, Li–S batteries evaluated under practical conditions exhibit significantly improved discharge capacity, rate capability, and cycling stability with the addition of the TFEB additive. More importantly, TFEB also contributes to the stabilization of lithium anode in the presence of polysulfides by generating strong interfacial film. These attributes significantly improve the cycling stability of practical Li–S pouch cells, which are assembled with a unit energy density of 219 Wh kg−1. The results provide new molecular insights on the design of unlocking solvation networks of practical Li–S systems. [ABSTRACT FROM AUTHOR]

Tungsten phosphide (WP) nanoparticles supported on nitrogen and phosphorus co-doped carbon nanosheets (WP@NPC) provide outstanding performance as a multifunctional separator in lithium-sulfur batteries, enabling higher sulfur utilization and exceptional rate capability. Its excellent performance is associated with the abundance of lithium polysulfide (LiPS) adsorption and catalytic conversion sites and swift ion transport within the separator. Key to these features is the sulfophilic character of W and the lithiophilicity of nitrogen and phosphorus, as well as the capability of WP to regulate the LiPS catalytic conversion, accelerating the Li-S redox kinetics. [Display omitted] Lithium-sulfur batteries (LSBs) hold great potential as future energy storage technology, but their widespread application is hampered by the slow polysulfide conversion kinetics and the sulfur loss during cycling. In this study, we detail a one-step approach to growing tungsten phosphide (WP) nanoparticles on the surface of nitrogen and phosphorus co-doped carbon nanosheets (WP@NPC). We further demonstrate that this material provides outstanding performance as a multifunctional separator in LSBs, enabling higher sulfur utilization and exceptional rate performance. These excellent properties are associated with the abundance of lithium polysulfide (LiPS) adsorption and catalytic conversion sites and rapid ion transport capabilities. Experimental data and density functional theory calculations demonstrate tungsten to have a sulfophilic character while nitrogen and phosphorus provide lithiophilic sites that prevent the loss of LiPSs. Furthermore, WP regulates the LiPS catalytic conversion, accelerating the Li-S redox kinetics. As a result, LSBs containing a polypropylene separator coated with a WP@NPC layer show capacities close to 1500 mAh/g at 0.1C and coulombic efficiencies above 99.5 % at 3C. Batteries with high sulfur loading, 4.9 mg cm−2, are further produced to validate their superior cycling stability. Overall, this work demonstrates the use of multifunctional separators as an effective strategy to promote LSB performance. [ABSTRACT FROM AUTHOR]

The lithium-sulfur battery (LSB) is a highly promising energy storage system with merits of exceptional theoretical specific capacity and energy density. However, challenges including insufficient sulfur conductivity, volume expansion, and the polysulfide shuttle effect result in rapid capacity decay and limited cycle life of the LSB, which significantly hinders its development. Inspired by the structure and forming process of paper, a fiber double network skeleton was constructed using flexible pulp fiber (PF) and highly conductive carbon fiber (CF). Following the principles of wet end chemistry in papermaking, MXene nanosheets with high adsorption and catalytic capacity for polysulfides were self-assembled on the surfaces of PF and CF to fabricate composite paper-based materials. The interwoven mesh of PF exhibited strong binding force and stable structure, providing support and protection for the CF interwoven mesh, resulting in a composite material with abundant porosity and excellent structural stability. Moreover, the CF interweaving network combined with an overlaid MXene interweaving network established an effective three-dimensional conductive pathway. When utilized as a self-supporting cathode in LSB, this composite paper-based material demonstrated outstanding cyclic stability. Under conditions of sulfur load at 2.3 mg·cm−2 and discharge at 0.2 C, the specific discharge capacity remained at 952 mAh·g−1 after 200 cycles with a capacity retention rate reaching 95.4%. The CF/PF@Mxene (CPCMX) also exhibited excellent tensile strength measured at 7.19 MPa while maintaining exceptional flexibility and electrolyte wettability. This research presents a highly promising solution for advancing the development of LSB with superior cycle stability. [ABSTRACT FROM AUTHOR]

The slow bidirectional conversion and fast shuttling of lithium polysulfides (LiPSs) remain the main obstacles that inhibit the practical application of lithium sulfur batteries (LSBs). Here, by engineering the in‐spin state of spinel oxides, V doping‐induced hexagonal nanosheets (V‐Co3O4 NS) with intermediate spin state (IS, t2g5 eg1) can form stable bond order toward LiS* based on the ligand field theory and molecular orbital theory, thus effectively accelerating the sulfur conversion kinetics. Owing to these merits, the V‐Co3O4 NS modified separator base battery achieves a high areal capacity of 15.37 mAh cm−2 with sulfur loading of 15.4 mg cm−2, and it displays a low‐capacity attenuation of 0.015% each cycle at 3.0 C for 1900 cycles. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur (Li–S) batteries are facing a multitude of challenges, mainly pertaining to the sluggish sulfur redox kinetics and rampant lithium dendrite growth on the cathode and anode side, respectively. In this sense, MXene has shown conspicuous advantages in serving as a dual‐functional promotor for Li–S batteries throughout the morphologic engineering, but still suffers from poor electrocatalytic activity and insufficient lithophilic sites. Herein, atomically dispersed Co sites are seeded onto the size effect‐enabled V2C MXene spheres (Co‐VC), leading to the generation of unique coordination configurations and rich active sites. Electrochemical tests combined with synchrotron radiation X‐ray 3D nano‐computed tomography and theoretical calculations unravel that Co‐VC with optimal coordination environments simultaneously boost sulfur reaction kinetics and lithium nucleation. As a consequence, Li–S batteries with Co‐VC modified separator can sustain a stable operation over 700 cycles with negligible capacity decay at 1.0 C, and delivers an areal capacity of 9.0 mAh cm−2 and desired cyclic performance at a high sulfur loading of 7.6 mg cm−2 with a lean electrolyte dosage of 4.0 µL mgS−1 at 0.1 C. The work opens a new avenue for boosting atomic‐scale site design with the aid of 2D substrates toward pragmatic Li–S batteries. [ABSTRACT FROM AUTHOR]

The shuttle effect and slow oxidation‐reduction reactions of the cathode in lithium‐sulfur batteries limit its practical application and development. Herein, porous carbon derived from pollen modified by black phosphorus nanosheets (BP/N−C) have been synthesized and utilized as a sulfur host in Li−S batteries. From the compositional outlook, the biomass‐derived carbon forms a unique three‐dimensional skeleton structure, exhibiting excellent properties, such as high porosity and high conductivity. Upon modified with black phosphorus, the BP/N−C composite materials demonstrate enhanced adsorption ability and catalytic activity toward lithium polysulfides (LiPSs). The BP/N−C/S cathode electrode presents a high initial specific discharge capacity of 1009.6 mAh g−1 and a low capacity decay rate of 0.08% per cycle during 150 cycles at 0.2 C rate. Besides, the BP/N C/S cathode electrode exhibits the superior rate performance (508 mAh g−1 at 5 C). [ABSTRACT FROM AUTHOR]

This paper presents a composed lithium phosphate (LiPON) solid electrolyte interface (SEI) film which was coated on a lithium electrode via an electrodeposit method in a lithium–sulfur battery, and the structure of the product was characterized through infrared spectrum (IR) analysis, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), environment scanning electron microscope (ESEM), etc. Meanwhile, the electrochemical impedance spectrum and the interface stability of the lithium electrode with the LiPON film was analyzed, while the coulomb efficiency and the cycle life of the lithium electrode with the LiPON film in the lithium–sulfur battery were also studied. It was found that this kind of film can effectively inhibit the charge from transferring at the interface between the electrode and the solution, which can produce a more stable interface impedance on the electrode, thereby improving the interface contact with the electrolyte, and effectively improve the discharge performance, cycle life, and the coulomb efficiency of the lithium–sulfur battery. This is of great significance for the further development of solid electrolyte facial mask technology for lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) are considered next‐generation energy storage and conversion solutions owing to their high theoretical specific capacity and the high abundance/low‐cost of sulfur‐based cathode materials. However, LSBs still encounter significant challenges, including the low conductivities of sulfur‐based materials, severe volumetric expansion of sulfur during the discharge process, and the persistent "shuttle effect" of polysulfides. In recent years, a tremendous amount of research has been conducted to address the above challenges by developing coating and compositing materials and corresponding fabrication strategies for sulfur‐based cathode materials. In this study, the surface coating, compositing materials, and fabrication methodologies of LSB cathodes are comprehensively reviewed in terms of advanced materials, structure/component characterization, functional mechanisms, and performance validation. Some technical challenges are analyzed in detail, and possible future research directions are proposed to overcome the challenges toward practical applications of lithium‐sulfur batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • One-step spinning for the production of hollow necklace-like carbon fiber. • CeO 2 /Co heterostructure exhibits catalytic performance and adsorption capabilities. • High surface area host material can effectively mitigate the volume expansion of sulfur. • CeO 2 /Co heterostructure facilitates the deposition and decomposition of Li 2 S. • At a current density of 2 C, the capacity decay is only 0.044 % per cycle. The shuttle effect of lithium polysulfides (LiPSs) and the sluggish reaction kinetics of LiPSs conversion pose serious challenges to the commercial feasibility of lithium-sulfur (Li-S) batteries. To address these obstacles, herein, we construct CeO 2 /Co heterostructures in hollow necklace-like carbon fibers (CeO 2 /Co-CNFs) as the cathode host material for Li-S batteries. The specific surface area of fibers is significantly enhanced by using a template, thereby promoting the utilization efficiency of sulfur. Meanwhile, CeO 2 /Co-CNFs show strong conductivity, effective adsorption to LiPSs, and robust catalytic activity for LiPSs conversion. As a result, the Li-S battery with CeO 2 /Co-CNFs displays 961 mAh g−1 at 0.2 C, with an 86 % capacity retention rate after 100 cycles. At 2.0 C current density, the composite cathode maintains an initial discharge capacity of 782 mAh g−1, with a mere 0.044 % capacity loss per cycle. Furthermore, in situations with limited electrolytes, high sulfur loading, and high areal mass loading, the composite cathode can provide a high areal capacity of 6.2 mg cm−2 over 100 cycles. This work provides a useful approach for investigating high-performance Li-S battery cathodes. [ABSTRACT FROM AUTHOR]

[Display omitted] The shuttle effect and sluggish redox kinetics of polysulfides have hindered the development of lithium – sulfur batteries (LSBs) as premier energy storage devices. To address these issues, a high - entropy metal phosphide (NiCoMnFeCrP) was synthesized using the sol – gel method. NiCoMnFeCrP, with its rich metal species, exhibits strong synergistic effects and provides numerous catalytic active sites for the conversion of polysulfides. These active sites, possessing significant polarity, can bond with polysulfides. In situ ultraviolet–visible were conducted to monitor the dynamic changes in species and concentrations of polysulfides, validating the ability of NiCoMnFeCrP to facilitate the conversion of polysulfides. The batteries with the NiCoMnFeCrP catalyst as functional separators exhibited minimal capacity decay rates of 0.04 % and 0.23 % after 100 cycles at 0 °C and 60 °C, respectively. This indicates that the NiCoMnFeCrP catalyst possesses good thermal stability. Meanwhile, its area capacity can reach 4.78 mAh cm−2 at a high sulfur load of 4.54 mg cm−2. In conclusion, NiCoMnFeCrP achieves the objective of mitigating the shuttle effect and accelerating the kinetics of the redox reaction, thereby facilitating the commercialization of LSBs. [ABSTRACT FROM AUTHOR]

The multi-cell coupling method is an effective way to solve the dynamic response problem of fuel cell power systems. However, it needs to control the stable output voltage to extend the service life of the power supply system. This article uses a PID controller to model and analyze proton exchange membrane fuel cells (PEMFCs). A lithium-sulfur battery (Li–S battery) model was established, and the discharge process of the lithium-sulfur battery was accurately simulated using the method of minimizing prediction error. These models are coupled through DC/DC boost converters to achieve a collaborative power supply system. The results indicate that the output voltage of the fuel cell is effectively stabilized at 24 V. The output voltage of the lithium-sulfur battery pack is designed to be 44–50 V. Each individual battery voltage is balanced to achieve a stable output voltage of 48 V. The system is powered by a proton exchange membrane fuel cell stack as the main power source and a lithium-sulfur battery pack as the auxiliary power source. At room temperature of 23 °C, the output voltage of the system can be stabilized within a controllable range of 48 V. Based on the operational characteristics and power demand analysis of the target ship, the basis for constructing a dual power source energy management strategy is elaborated. On this basis, fuzzy control was designed with ship demand power and lithium battery SOC as inputs and lithium battery output power as system output. An improved state flow controller was constructed by adding a ship demand power limiting unit to the logic threshold strategy that originally only had lithium battery SOC as the threshold. [ABSTRACT FROM AUTHOR]

Sulfur‐polyacrylonitrile (SPAN) is a sulfur‐based active material for next‐generation lithium‐sulfur battery cathodes. Due to the covalent bonding between sulfur chains and the polymeric backbone, the shuttle effect degrading classical sulfur‐based cathodes can be suppressed while also achieving a high active material content in the cathode. In this paper, we investigate the processability of an industrially scalable SPAN active material with 38 wt.‐% of sulfur in a water‐based and scalable process route. The potential of the SPAN material for industrial adoption and the impact of the process route on the cell performance are discussed. We show that when processed correctly, the SPAN material delivers exceptional cycling stability and good C‐rate performance with ether‐based electrolytes. However, the performance of the SPAN cathode is influenced by the mixing characteristic. Using higher mixing intensities during the slurry preparation leads to deterioration of the electrochemical performance. This can be attributed to a decreasing carbon black percolation with increasing tip speed in combination with the kinetic limitation of sulfur cathodes during Li2S2 and Li2S oxidation. [ABSTRACT FROM AUTHOR]

The inevitable shuttling and slow redox kinetics of lithium polysulfides (LiPSs) as well as the uncontrolled growth of Li dendrites have strongly limited the practical applications of lithium‐sulfur batteries (LSBs). To address these issues, we have innovatively constructed the carbon nanotubes (CNTs) encapsulated Co nanoparticles in situ grown on TiN‐MXene nanosheets, denoted as TiN‐MXene‐Co@CNTs, which could serve simultaneously as both sulfur/Li host to kill "three birds with one stone" to (1) efficiently capture soluble LiPSs and expedite their redox conversion, (2) accelerate nucleation/decomposition of solid Li2S, and (3) induce homogeneous Li deposition. Benefiting from the synergistic effects, the TiN‐MXene‐Co@CNTs/S cathode with a sulfur loading of 2.5 mg cm−2 could show a high reversible specific capacity of 1129.1 mAh g−1 after 100 cycles at 0.1 C, and ultralong cycle life over 1000 cycles at 1.0 C. More importantly, it even achieves a high areal capacity of 6.3 mAh cm−2 after 50 cycles under a sulfur loading as high as 8.9 mg cm−2 and a low E/S ratio of 5.0 μL mg−1. Besides, TiN‐MXene‐Co@CNTs as Li host could deliver a stable Li plating/striping behavior over 1000 h. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of lithium‐sulfur (Li−S) batteries severely impedes the application in extreme conditions. Bridging the sulfur cathode and lithium anode, the electrolyte plays a crucial role in regulating kinetic behaviors of Li−S batteries. Herein, we report a multifunctional electrolyte additive of phenyl selenium bromide (PhSeBr) to simultaneously exert positive influences on both electrodes and the electrolyte. For the cathode, an ideal conversion routine with lower energy barrier can be attained by the redox mediator and homogeneous catalyst derived from PhSeBr, thus improving the reaction kinetics and utilization of sulfur. Meanwhile, the presence of Se−Br bond helps to reconstruct a loose solvation sheath of lithium ions and a robust bilayer SEI with excellent ionic conductivity, which contributes to reducing the de‐solvation energy and simultaneously enhancing the interfacial kinetics. The Li−S battery with PhSeBr displays superior long cycling stability with a reversible capacity of 1164.7 mAh g−1 after 300 cycles at 0.5 C rate. And the pouch cell exhibits a maximum capacity of 845.3 mAh and a capacity retention of 94.8 % after 50 cycles. Excellent electrochemical properties are also obtained in extreme conditions of high sulfur loadings and low temperature of −20 °C. This work demonstrates the versatility and practicability of the special additive, striking out an efficient but simple method to design advanced Li−S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] People have been focusing on how to improve the specific capacity and cycling stability of lithium-sulfur batteries at room temperature, however, on some special occasions such as cold cities and aerospace fields, the operating temperature is low, which dramatically hinders the performance of batteries. Here, we report an iron carbide (Fe 3 C)/rGO composite as electrode host, the Fe 3 C nanoparticles in the composite have strong adsorption and high catalytic ability for polysulfide. The rGO makes the distribution of Fe 3 C nanoparticles more disperse, and this specific structure makes the deposition of Li 2 S more uniform. Therefore, it realizes the rapid transformation and high performance of lithium-sulfur batteries at both room and low temperatures. At room temperature, after 100 cycles at 1C current density, the reversible specific capacity of the battery can be stabilized at 889 ± 7.1 mAh/g. Even at −40 °C, in the first cycle battery still emits 542.9 ± 3.7 mAh/g specific capacity. This broadens the operating temperature for lithium-sulfur batteries and also provides a new idea for the selection of host materials for sulfur in low-temperature lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

Highlights: By introducing fluorine modulation into MXene, a new MXene-derived material TiOF/Ti3C2 was successfully synthesized with a distinctive three-dimensional structure and a tailored F distribution. In situ characterizations and electrochemical analyses demonstrate that TiOF/Ti3C2 catalysts effectively coupled the multiphase sulfur species conversion processes. The investigations reveal that the theoretical basis of the fluorine catalysis in Li–S batteries originated from Lewis acid–base mechanisms and charge compensation mechanisms. Fluorine owing to its inherently high electronegativity exhibits charge delocalization and ion dissociation capabilities; as a result, there has been an influx of research studies focused on the utilization of fluorides to optimize solid electrolyte interfaces and provide dynamic protection of electrodes to regulate the reaction and function performance of batteries. Nonetheless, the shuttle effect and the sluggish redox reaction kinetics emphasize the potential bottlenecks of lithium–sulfur batteries. Whether fluorine modulation regulate the reaction process of Li–S chemistry? Here, the TiOF/Ti3C2 MXene nanoribbons with a tailored F distribution were constructed via an NH4F fluorinated method. Relying on in situ characterizations and electrochemical analysis, the F activates the catalysis function of Ti metal atoms in the consecutive redox reaction. The positive charge of Ti metal sites is increased due to the formation of O–Ti–F bonds based on the Lewis acid–base mechanism, which contributes to the adsorption of polysulfides, provides more nucleation sites and promotes the cleavage of S–S bonds. This facilitates the deposition of Li2S at lower overpotentials. Additionally, fluorine has the capacity to capture electrons originating from Li2S dissolution due to charge compensation mechanisms. The fluorine modulation strategy holds the promise of guiding the construction of fluorine-based catalysts and facilitating the seamless integration of multiple consecutive heterogeneous catalytic processes. [ABSTRACT FROM AUTHOR]

A dense electrode with high sulfur loading is a straightforward approach to increasing the energy density of lithium–sulfur battery (LSB), but the development of dense electrodes suffers from both fabrication challenges and electron/ion transport limitations. In addition, the shuttle effect of soluble lithium polysulfides and sluggish reaction kinetics cause declined utilization efficiency of the active material and poor cycling stability. Herein, a dense intercalation‐conversion hybrid cathode is prepared using MXene‐driven TiS2 nano‐needles decorated with TiO2 nanoparticles. The TiO2/TiS2 heterostructure simultaneously possessing a high adsorption capability (TiO2) and bidirectional electrocatalytic effect (TiS2) is observed to effectively suppress lithium polysulfide shuttling and facilitate the sulfur conversion reactions. Furthermore, it is believed that TiS2 provides additional capacity from the intercalation reaction and functions as a multichannel network to feed both Li+/e− to the active sulfur material due to its high electronic and ionic conductivities. Thanks to these synergistic effects, the LSB assembled using the TiO2/TiS2 heterostructure exhibits high gravimetric and volumetric energy densities of 331 Wh kg−1 and 730 Wh L−1, respectively, as well as superior cyclability at a high sulfur mass loading of 7.5 mg cm−2 and lean electrolyte of 2.5 μL mg−1. [ABSTRACT FROM AUTHOR]

Due to their high energy density and cost‐effectiveness, lithium–sulfur batteries (LSBs) are considered highly promising for the next generation of energy storage technologies. However, the soluble lithium‐polysulfides (LiPSs) notorious for causing the shuttle effect and the sluggish redox kinetics have hindered their practical commercialization. To tackle these challenges, a heterostructural catalyst featuring NiS‐NiCo2O4 interfaces is developed, which serves as an interlayer for LSBs. These interfacial sites leverage the advantages of polar NiCo2O4 and conductive NiS, enabling smooth Li+ diffusion, rapid electron transport, and effective immobilization of LiPSs. This synergistic approach promotes the conversion of sulfur species, resulting in a high discharge capacity of 526 mAh g−1 at 3 C for cells with the NiS‐NiCo2O4 interlayer. Additionally, remarkable cycling stability is achievable with an areal sulfur loading of ≈5.0 mg cm−2. It is believed that this research paves the way for practical applications of LSBs. [ABSTRACT FROM AUTHOR]

Due to their low cost, environmental friendliness and high energy density, the lithium-sulfur batteries (LSB) have been regarded as a promising alternative for the next generation of rechargeable battery systems. However, the practical application of LSB is seriously hampered by its short cycle life and high self-charge owing to the apparent shuttle effect of soluble lithium polysulfides. Using MgSO4@MgO composite as both template and dopant, template-guided S-doped mesoporous graphene (SMG) is prepared via the fluidized-bed chemical vapor deposition method. As the polypropylene (PP) modifier, SMG with high specific surface area, abundant mesoporous structures and moderate S doping content offers a wealth of physical and chemical adsorptive sites and reduced interfacial contact resistance, thereby restraining the serious shuttle effects of lithium polysulfides. Consequently, the LSB configured with mesoporous graphene (MG) as S host material and SMG as a separator modifier exhibits an enhanced electrochemical performance with a high average capacity of 955.64 mA h g-1 at 1C and a small capacity decay rate of 0.109% per cycle. Additionally, the density functional theory (DFT) calculation models have been rationally constructed and demonstrated that the doped S atoms in SMG possess higher binding energy to lithium polysulfides than that in MG, indicating that the SMG/PP separator can effectively capture soluble lithium polysulfides via chemical binding forces. This work would provide valuable insight into developing a versatile carbon-based separator modifier for LSB. [ABSTRACT FROM AUTHOR]