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Lithium‐sulfur (Li‐S) batteries are in the spotlight because their outstanding theoretical specific energy is much higher than those of the commercial lithium ion (Li‐ion) batteries. Li‐S batteries are tough competitors for future‐developing energy storage in the fields of portable electronics and electric vehicles. However, the severe "shuttle effect" of the polysulfides and the serious damage of lithium dendrites are main factors blocking commercial production of Li‐S batteries. Owing to their superior nanostructure, electrospun nanofiber materials commonly show some unique characteristics that can simultaneously resolve these issues. So far, various novel cathodes, separators, and interlayers of electrospun nanofiber materials which are applied to resolve these challenges are researched. This review presents the fundamental research and technological development of multifarious electrospun nanofiber materials for Li‐S cells, including their processing methods, structures, morphology engineering, and electrochemical performance. Not only does the review article contain a summary of electrospun nanofiber materials in Li‐S batteries but also a proposal for designing electrospun nanofiber materials for Li‐S cells. These systematic discussions and proposed directions can enlighten thoughts and offer ways in the reasonable design of electrospun nanofiber materials for excellent Li‐S batteries in the near future. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and theoretical capacity, but the rapid decay of capacity is still a huge challenge. Herein, we reported an ingenious design of nitrogen doped carbon nanofibers with honeycomb-like porous structure for the cathode of lithium-sulfur battery which can effectively suppress the “shuttle effect”. The special porous material with three dimensional (3D) interconnected pore structure is beneficial to enhance the adsorption of lithium polysulfides and accommodate the volume expansion of active materials. In addition, the doped nitrogen can not only improve the conductivity of cathode, but also form a strong interfacial interaction to trap lithium polysulfides. Therefore, the battery with the cathode exhibited a high reversible discharge capacity of 1093.9 mAh g −1 and good capacity retention of 76.0% after 300 cycles at 0.5C rate. After acidification, the cycling performance of the cathode could achieve upon 300 cycles with a very low decay rate of 0.027% at 0.5C. [ABSTRACT FROM AUTHOR]

The honeycomb-like hierarchical porous carbon nanofibers (PCNFs)-carbon nanotubes (CNTs)-sulfur(S) composite electrode is successfully desgined and prepared through ball-milling and heating method, in which the PCNFs are carbonized from fibers in the membrane composed of Polyvinyl Alcohol and Polytetrafluoroethylene by electro-blown spinning technology. The prepared PCNFs-CNTs-S composite are regarded as cathode for lithium-sulfur battery. The tailored porous structure and CNTs in the composite facilitate construction of a high electrical conductive pathway and store more S/polysulfides, and the dissoluble loss of intermediate S species in electrolyte can also be restrained because of acidized PVA-based porous carbon nanofibers. Meanwhile, the porous strcucture and CNTs can effectively alleviate volume changes in battery cycling process. Moreover, the presence of LiNO 3 in electrolyte helps the electrochemical oxidation of Li 2 S and LiNO 3 -derived surface film effectively suppresses the migration of soluble polysulfide to the Li anode surface. Therefore, the obtained PCNFs-CNTs-S cathode exhibits excellent performance in Li-S battery with a high initial discharge capacity as high as 1302.9 mAh g −1 , and super stable capacity retention with 809.1 mAh g −1 after 300 cycles at the current density of 837.5 mA g −1 (0.5 C). And the rate capability of PCNFs-CNTs-S electrode is much better than those of CNTs-S and PCNFs-S electrodes. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries have been considered as one of the most promising energy storage candidates due to their high energy density and low cost. However, the low electrical conductivity of elemental sulfur, notorious LiPS shuttle and sluggish redox kinetics bring about fast capacity fade and poor rate capabilities. To solve these problems, herein a modification strategy of functional separator is introduced by coating heterostructured MoP–MoS 2 and porous carbon nanofibers (PCNFs) on the surface of a Celgard separator. Moreover, for the first time, we detailly discuss the effect of the ratio of component (MoP:MoS 2) in the heterostructured MoP–MoS 2 materials on the electrochemical performance. The coating layer exhibits both satisfactory interception ability for LiPS shuttle and fast LiPS conversion ability due to abundant anchoring sites of MoP–MoS 2 heterojunction nanoflowers and shortened lithium ion channel of the prepared PCNFs. Benefiting from these advantages, the assembled Li–S battery with a MoP-50/PCNFs separator exhibits 1090.02 mAh g-1, and high discharge capacity of 884.67 mAh g-1 even after 300 cycles at 1 C. The initial discharge capacity of MoP-50/PCNFs separator at 2 C and 5 C are about 1050.4 and 728.22 mAh g-1, and retains about 698.4 mAh g-1 after 400 cycles and 431.28 mAh g-1 after 500 cycles. The novel work will provide a new strategy by which the modified separator with transition metal phosphides can be applied in the design of high-performance Li–S batteries and shows great potential for practical application. MoP-x/PCNFs modified Celgard separator in Lithium-sulfur battery. [Display omitted] • Preparing Flower-like heterostructured MoP–MoS 2. • Designing various heterostructured MoP–MoS 2 materials (MoP: MoS 2 = 100:0, 75:25, 50:50, 25:75, 0:100). • Porous carbon nanofiber with dual functions of lithium polysulfudes adsorption through one-step electrostatic blowing method. • Researching the catalytic kinetic mechanism of the "solid-liquid-solid" mutual conversion process for transition metal phosphide. • Exploring the cycle performance of Celgard separator modified with MoP–MoS 2 -50/PCNFs. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery is regarded as one of the promising next-generation energy storage to electrical and portable devices thanks to its extremely high theoretical capacity, energy density, good environmental protection and low cost. However, the practical application of lithium-sulfur battery is still greatly impeded by the low Coulombic efficiency and the short lifespan, which is mainly attributed to the polysulfide shuttle and the uncontrollable lithium dendrite growth. Suppressing the growth of the lithium dendrite and hindering the notorious reaction between soluble polysulfides and lithium are extremely critical not only to a safe and efficient lithium anode, but also to the high-capacity lithium-sulfur battery. A comprehensive review of various strategies for strengthening the anode stability of lithium-sulfur battery is presented in this paper, including modifying the electrolyte and current collector, employing artificial protection films and finding alternative anodes to replace the lithium anode. The effects of different selections and the resulting properties of the anodes on the overall lithium-sulfur battery performance are discussed. The current research challenges and future perspectives associated with lithium-sulfur battery anode are also discussed. [ABSTRACT FROM AUTHOR]

In this study, F-doped tree-like nanofiber structural poly-m-phenyleneisophthalamide (PMIA) membranes are prepared via one-step electrospinning approach and their application performance as separators for lithium-sulfur batteries are discussed. The F-doped PMIA membrane can be regarded as matrix to form gel polymer electrolyte. The F doping endows the PMIA membranes with extraordinary high electrolyte uptake, excellent ability of preserving the liquid electrolyte and forceful chemisorption to polysulfides. And the tree-like structure effectively blocks polysulfides by the physical confinement. The lithium-sulfur cell with the F-doped PMIA separator exhibits high first-cycle discharge capacity of 1222.5 mAh g −1 and excellent cycling stability with good capacity retention of 745.7 mAh g −1 and coulombic efficiency of 97.97% after 800 cycles. The remarkable performance can be ascribed to the suppressed shuttle effects through both the physical trapping of polysulfides by the gel polymer electrolyte based on matrix with F-doped PMIA membrane and the tree-like structure in a working cell. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery is considered as one of high performance batteries of the new generation owing to its extremely high theoretical capacity, energy density, good environmental protection and low cost. These features make it of great significance to serve as the next-generation battery especially in electric vehicles and portable devices. However, the practical application of lithium-sulfur battery is still hindered due to some obstacles including the low electrical and ionic conductivity of elemental sulfur, the discharge product Li 2 S and the “shuttle effect” caused by the dissolved polysulfide species. In this review, the current trends, fundamental studies and developments for lithium-sulfur battery separators including some modified functional and novel battery separators with the customized structure designs are presented and reviewed. The effects of different selections and the resulting properties of the separators affecting the overall lithium-sulfur battery performances are discussed as well. The current research directions and challenges associated with the use of battery separator and the future perspectives for this class of the battery separator are concluded as well. [ABSTRACT FROM AUTHOR]

• A novel multifunctional interlayer is successfully prepared. • The prepared interlayer mainly contains N-doped porous carbon nanofibers and Mg-Al layered double hydroxides. • The interlayer can suppress the "shuttle effect" and accelerate the redox reaction kinetics. • The Li-S battery with the MALDH@NPCNFs interlayer shows stable long-term cycle performance. [Display omitted] Lithium-sulfur (Li-S) battery as a promising energy storage technology has attracted extensive concern. However, their practical performance is seriously limited by the dissolution and diffusion of long-chain polysulfides. In this study, a multifunctional cathodic interlayer was constructed, which composed by Mg-Al layered double hydroxides (MALDHs) modified N-doped honeycomb-like porous carbon nanofibers (NPCNFs). The NPCNFs in the prepared interlayer can combine the physical confinement of the porous structure and the chemical role of the nitrogen atoms to suppress the dissolved lithium polysulfide (LiPS). Furthermore, highly conductive interlayer contains NPCNFs can be regarded as a second current collector, and the hierarchical pores is beneficial to adapt the volume change during the redox process. More importantly, the obtained polar MALDHs not only can strongly interact with LiPS by chemical combination, but also enhance the redox kinetics by forming cooperative interface. As a result, the Li-S cells with the cathodic interlayers obtains a high initial discharge capacity of 1452 mAh g−1 at 0.2 C, superior rate capability up to 2 C rate with a capacity of 952 mAh g−1 and excellent long-term cycling stability by maintaining a low average capacity fading (0.065% per cycle) during 500 cycles at 1 C. Therefore, the interlayer contains MALDH@NPCNFs has extraordinary potential to be used in high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

Owing to high energy density, lithium sulfur (Li–S) battery is regarded as one of the most promising candidates for future energy storage. However, "shuttle effect" and sluggish redox kinetics of lithium polysulfides impede its practical application. Herein, a novel g-C 3 N 4 /Co-based MOFs derived chestnut-like superstructure (Co/CNT@DCNS) was prepared to act as the component of interlayer through a low-temperature one-step carbonization strategy. The prepared superstructure was constructed by the strong catalysis of 0D Co nanoparticles, high conductivity of 1D CNTs and excellent polysulfides adsorption of 2D defect C x N y nanosheets, which could not only ensure the rapid electrons/ions transport and fast redox kinetics, but also provide sufficient spaces for accommodating the volume expansion of active materials. Therefore, the cells with the prepared interlayer exhibited stable performances with an initial capacity of 1348.3 mAhg−1 and an extended cycling stability of 0.04% per cycle during the 1000 cycles at 1C. Even at a high sulfur loading of 3.1 mg cm−2, a specific capacity of 691.7 mAh g−1 can be maintained after 500 cycles at 0.5C. This work shares a convenient and safe strategy for the synthesis of multi-dimension, dual-functional and stable superstructure interlayer for advanced Li–S batteries. Image 1 [ABSTRACT FROM AUTHOR]