The growing demand for wearable electronics and smart textiles has intensified research into flexible, miniaturized, high-performance, and safe energy storage devices. Lithium-sulfur (Li-S) batteries, with their high theoretical energy density supported by sulfur's multielectron chemistry and cost-effectiveness, are highly promising, yet they face critical bottlenecks. These challenges include low long-cycle capacity retention and inadequate cycling durability during bending. Conventional materials such as graphene and conductive polymers fall short in interface stability or scalable synthesis, failing to balance electrical conductivity with mechanical strength simultaneously. MXene emerges as a breakthrough, offering metal-grade conductivity, tunable surface chemistry, abundant functional groups, and exceptional mechanical resilience. Its layered structure not only anchors polysulfides but also withstands repeated deformations. This review systematically examines the design strategies for Li-S batteries that integrate flexibility, high energy density, and cycling stability. Firstly, synthesis, structure, properties, and analysis of advantages of MXene used in Li-S batteries are summarized. Subsequently, computational and simulation approaches are employed to analyze MXene's role in addressing shuttle effects and lithium dendrite growth. Applications of MXene-based materials in various components of flexible Li-S batteries are then discussed. Finally, insights are provided on challenges and future developments for MXene-based flexible Li-S batteries.

Three-dimensional (3D) carbonaceous hosts are ideal for lithium metal anodes (LMAs) owing to their lightweight architecture and high conductivity. However, spatial inhomogeneities in Li+ concentration and electric fields induce detrimental "top-growth" lithium deposition and dendrite formation. To overcome this challenge, a vertically graded 3D carbon fiber framework with functionally stratified silver nanoparticles (Ag NPs) layers (VGCF-Ag) is engineered. It comprises three functional layers: a bottom induction layer enriched with ultrathin Ag NPs to guide downward Li+ diffusion and enable preferential nucleation; a middle growth layer with fully exposed Ag NPs to ensure uniform Li deposition; a top lithiophobic layer with reduced fiber diameter to facilitate the downward migration of Li+ while serving as a buffer for Li growth. Characterization and simulations confirm that VGCF-Ag enables controlled "bottom-up" deposition by regulating Li+ kinetics and electrochemical deposition behavior. Electrochemical tests demonstrate exceptional performance, including stable cycling for 600 cycles in half-cells, over 2000 h in symmetric cells at 1 mA cm-2, and 92.2% capacity retention in full-cells after 800 cycles at 3C. Even at a low N/P ratio, it still shows remarkable performance. This vertically graded multifunctional layer design effectively suppresses dendrites, offering a scalable paradigm for high-energy-density batteries.

Although polymer electrolytes constructed by in-situ curing of cyclic ethers show great application potential, they also face challenges such as poor oxidation stability and low lithium-ion transference number. Herein, a strategy is proposed to fabricate a network structural composite polymer electrolyte (CPE) via in situ hybrid crosslinking polymerization, using nano-UIO66 as the centers and DOL as the polymeric matrix (PDOL@UIO66). This design not only enhances the ionic conductivity of the CPE, but also addresses the issues of filler sedimentation and agglomeration associated with conventional composite electrolytes. Moreover, the incorporation of MOF fillers contributes to further improvements in both the stability and electrochemical performance of the CPE. As a result, the PDOL@UIO66 electrolyte achieves a high ionic conductivity of 1.31 x 10-3 S cm-1 and a satisfactory oxidation potential of 4.8 V. These properties enable the PDOL@UIO66-based lithium symmetric battery exhibit exceptional cycling stability over 1100 h at 0.2 mA cm-2. And the capacity retention of the prepared LiCoO2 and NCM523/Li quasi-solid state batteries reached 86.1% after 500 cycles and 87.4% after 200 cycles at room temperature. This strategy of constructing hybrid crosslinking CPE utilizing MOF as the center through in situ polymerization provides new insights for the commercialization of high energy density lithium metal batteries.

Due to their unique anion and cation redox mechanisms, Li-rich Mn-based layered oxide cathodes are considered extremely promising candidates for next-generation high-performance Li-ion batteries. However, their practical applications are limited by capacity degradation, voltage degradation, and poor rate performance. In this work, an O2/O3 composite Li-rich cathode was constructed by integrating nanoscale O3 particles on the surface of O2 microspheres. By combining the inherent excellent voltage retention of the O2-type structure with the nanostructured O3 rate advantage, the O2/O3 composite cathodes exhibit excellent specific capacity, cycling stability, and rate performance. Thanks to the synergistic effect of O2 and O3, the obtained composite cathode has a high discharge specific capacity of 298.06 mAh g-1 at 0.1C. It maintains 85.34% capacity retention after 100 cycles at 0.5C and still delivers a discharge specific capacity of 144.64 mAh g-1 at 5C. Based on experiments and theoretical calculations, the potential impact of the O2/O3 interface on electrochemical performance is elucidated. The built-in electric field at the two-phase interface plays a crucial role in structural stability. The O2/O3 composite cathode developed in this study holds potential to advance the development of high-performance Li-ion batteries.

Gallium-based liquid metal (Ga-LM) anodes are of particular interest for lithium-ion batteries owing to the unique liquid-solid phase transition. Nevertheless, the inevitable volume expansion of Ga-LM during lithiation cannot be accommodated by rigid encapsulation, causing electrical isolation and rapid capacity decay. This study exploits the in‑situ phase separation of eutectic gallium indium (EGaIn) alloy, enabled by electrospinning‑derived carbon encapsulation, to generate a 3D carbon nanofiber (CNF) network comprising yolk-shell Ga2O3@CNF structures and uniformly dispersed In nanoparticles. The preferential oxidation of Ga during carbonization drives phase separation of EGaIn into Ga2O3 and metallic In, accompanied by the migration of In onto CNFs and the concomitant formation of yolk‑shell voids. As confirmed by finite element analysis (FEA) and density functional theory (DFT) calculations, the yolk-shell structure accommodates volume change and relieves interfacial stress, while the In nanoparticles mitigate ohmic polarization and provide atomic-scale Li adsorption sites. Benefiting from these merits, the phase-separated electrode achieves outstanding cycling stability, with a capacity decay of merely 0.014% per cycle over 2000 cycles at 3 A g-1, and a superior rate capability of 579.3 mAh g-1 at 3 A g-1. This work establishes the in‑situ phase‑separation strategy as a compelling route toward high‑performance Ga-LM‑based energy storage.

Driven by the demand for ultrahigh theoretical energy densities, Li–S batteries are highly attractive for the low-altitude economy and embodied robotics. However, their commercial application is critically bottlenecked by the Sabatier trade-off between efficient polysulfide trapping and rapid catalytic conversion. Herein, we propose a mechanism-guided research paradigm of “DFT prediction-Material preparation-Performance verification” to systematically screen Te-modified carbon materials, integrating the frequently overlooked role of oxygen during synthesis as a critical variable to develop advanced sulfur hosts. Theoretical analysis reveals that Te–O paris modulate the p-band center of the carbon matrix to optimize the adsorption energy of LiPSs, while significantly lowering the activation barriers for sulfur species conversion through localized electron donation. Guided by these theoretical insights, the TOC cathode exhibits an ultrahigh initial specific capacity and outstanding rate performance, achieving remarkable long-term stability over 2000 cycles even at a high rate of 4 C. Furthermore, under stringent practical conditions of high areal sulfur loading and low electrolyte, the TOC cathode achieves a superior areal capacity of 4.8 mAh cm–2. This work presents a new approach to designing sulfur hosts, accelerating the commercialization of practical Li–S batteries.

Solid-state lithium metal batteries, with high theoretical specific capacity and safety, have received significant attention. However, issues such as uneven lithium-ion flux and lithium dendrites limit their further application. Herein, we designed a composite polymer electrolyte (CPE) prepared by electrospinning a 3D interconnected functionalized Metal Organic Framework (MOF) network loaded with fluorinated-UIO66 (FUIO66) nanoparticles and in-situ polymerization of 1,3-dioxosolane (DOL). This structure improved the conductivity of Li+ (3.96 x 10-4 S cm-1) and enhanced the resistance of high voltage (4.8 V) by promoting the generation of long-chain polyDOL (PDOL) through the strong Lewis acidity of FUIO66. In addition, the F groups in the micropore strengthened the trapping of bis(trifluoromethanesulfonyl)imide (TFSI-) as well as the uniform deposited of LiF solid electrolyte interfaces (SEI), which facilitated the efficiency of Li+ conduction and limited the formation of Li dendrites. Consequently, the Li/FUIO66/PAN fiber@PDOL (FPF@PDOL)/Li battery showed good stability for 1200 h at 0.2 mA cm-2, and the capacity retention of the prepared LiFePO4 and LiCoO2/Li solid-state batteries reached 91 % after 400 cycles and 82 % after 500 cycles at room temperature. This research provides a new idea for the preparation of solid electrolytes with good ion transport kinetics and interfacial compatibility.

Composite solid electrolytes hold the promise of merging complementary merits of solid polymer electrolytes and ceramic fillers to achieve solid batteries with comprehensive performance. Especially, three-dimensional inorganic electrolyte frameworks, such as Li7La3Zr2O12, with fast and continuous lithium ion migration channels demonstrate great promise in composite solid electrolytes. Nevertheless, brittle ceramic conductor skeletons are incapable of providing sufficient mechanical adaptability, which restricts their practical application. Herein, a flexible, ion-conducting network which integrates Li7La3Zr2O12 nanoparticles in polyacrylonitrile nanofibers is fabricated through electrospinning method. Subsequently, a composite electrolyte with three-dimensional continuous structure is achieved via in situ polymerizing of 1,3-dioxolane within the ionic conduction framework. The highly conductive Li7La3Zr2O12 reinforced polymer nanofibers are not only available to promote transportation of lithium ion, but also provide structural flexibility and mechanical robustness for composite electrolyte. Accordingly, the obtained composite electrolyte combines enhanced room temperature ionic conductivity (4.38 x 10-4 Scm-1) with structural flexibility and mechanical robustness, supported by exceptional interfacial compatibility with lithium metal, enabling ultra-stable lithium symmetric battery operation (3000 h at 0.1 mAcm-2). Furthermore, as-prepared LiFePO4 and LiCoO2/lithium solid-state batteries deliver high capacity retention of 96% after 350 cycles and capacity retention of 82% after 600 cycles at room temperature. This work provides a new avenue in design of advancing composite solid electrolytes.

Nonaqueous rechargeable flexible lithium-oxygen batteries (LOBs) offer a promising candidate for next-generation energy storage. However, due to sluggish cathodic reaction kinetics combined with instability issues arising from Li anode corrosion, the efficient and stable operation of ampere hour (Ah) LOBs, which is key to practical application, remains a critical challenge. In this work, the overall battery configuration was systematically optimized by leveraging synergistic interactions between the cathode and anode electrodes. We report a self-supporting MnTe/MnTe2 heterostructure anchored on nitrogen-doped carbon nanofibers (MnTe/MnTe2@NCF), engineered through the modulation of p-orbital configurations. The structural optimization facilitates enhanced electrochemical reaction kinetics, endowing the cathode with superior catalytic performance as an advanced cathode. Concurrently, a robust hybrid Li2Te/Te/LiCl demonstrates improved mechanical stability and toughness, which proves its efficacy as a high-performance protective layer for the lithium anode. As a result, the fabricated LOBs demonstrate notable performance, including a low discharge/charge polarization of 0.761 V, a high specific capacity of 13,702.3 mAh g-1, and a long cycle life exceeding 440 cycles. Moreover, an optimized Li-O2 pouch cell based on the MnTe/MnTe2@NCF cathode exhibits a boosted energy density of 588.7 Wh kg-1, providing a technical pathway for high-energy-density LOBs.

The surface of the cathode materials is an outpost for dealing with structural degradation and unfavorable side reactions with the electrolyte, and surface engineering to improve the inherent defects of Li-rich Mn-based oxides (LRMO) is a highly promising strategy. Herein, surface functional modification of LRMO was achieved through a one-step solid-phase method using thioacetamide (TAA), which successfully introduced S doping and in situ induced spinel thin layers on the surface of Li1.2Mn0.54Ni0.13Co0.13O2. This integrated surface modification strategy combines the advantages of doping and coating single modifications to obtain TAAS-LRMO with superior cycling stability and rate performance. The capacity retention of TAAS-LRMO after 100 cycles is as high as 89.1% better than that of the bare LRMO (72.3%), while the average voltage decay is reduced from 7.04 mV to 4.71 mV. And the energy density retention of the modified sample rose from 60.2% to 79.5%. Experimental characterization and theoretical calculations jointly reveal that the modulation of the local electronic structure through S doping leads to enhanced transition metal-oxygen (TM-O) covalency and an increased formation energy of oxygen vacancies. Together with the protective effect of the spinel coating, these factors improve structural stability during the cycling process. Additionally, the reduced band gap and lower lithium-ion migration energy induced by S doping and the three-dimensional lithium-ion transport channels provided by the spinel structure synergistically promote redox kinetics. This work provides a new integrated surface modification approach to commercializing Li-rich Mn-based oxide cathodes.

With the rapid development of flexible electronic devices, wearable equipment, and implantable medical devices, there is an increasing demand for flexible energy storage devices. Polyacrylonitrile and polyurethane are cross-linked and polymerized using the phase transformation process under the action of a non-solvent phase, resulting in a three-dimensional skeleton for flexible, self-supporting thick electrodes that exhibit a threedimensional porous structure. In this structure, polyurethane serves as a flexible component, while the chainlike conductive agent KB provides electronic conduction pathways for the active material. Carbon nanofibers function as bridges between active particles, facilitating electronic transfer among them. Additionally, carbon nanotubes in the non-solution phase form an external conductive network within the three-dimensional electrode. The prepared three-dimensional porous flexible thick electrodes can control the electrode thickness to be above 300 mu m, with a capacity retention rate of 97.74 % after 200 cycles. They still exhibit a specific capacity of 133.39 mAh g-1 at a current density of 2.0C. This represents a significant improvement compared to traditional self-supporting electrodes.

Lithium-sulfur (Li-S) batteries have attracted considerable attention due to their high theoretical energy density and environmental friendliness. However, their practical applications are limited by the shuttle effect and sluggish conversion kinetics. In this work, we successfully design and precisely construct o-CoTe2|P nanoparticles on a 3D ordered porous carbon matrix from the perspective of "vacancy occupation-phase transformation coupling" for efficient and durable Li-S batteries. DFT theoretical calculations demonstrate that the o-CoTe2|P not only facilitates the redistribution of local charges, forming efficient adsorption sites for anchoring LiPSs, but also optimizes electronic transport pathways, significantly reducing the energy barrier. Thus, it achieves the synergistic regulation of the "anchoring-diffusion-conversion" process of sulfur species. Electrochemical results demonstrate that the o-CoTe2|P@S cathode exhibits an extremely high initial specific capacity of 1237.72 mAh g- 1 at 0.2C and an ultralow capacity decay rate of 0.038 % per cycle with 1000 cycles at 4C. Furthermore, the flexible pouch cell with precisely integrated GPE and copper mesh-reinforced flexible Li-metal composite anode demonstrates superior mechanical and safety properties. This study provides valuable insights into the rational design of electrocatalysts for advanced Li-S batteries.

Lithium-sulfur batteries are regarded as ideal energy storage systems due to their high specific capacity and low cost. However, their large-scale application has been severely hindered by issues such as the shuttle effect and volume expansion, making the development of efficient catalysts imperative. This work utilized VASP simulation software to construct Ti3C2T2 MXene models to deeply explore its catalytic mechanism for lithium polysulfide (LiPSs) conversion. The simulation results determined the site of MXene surface terminals, identified the most stable adsorption configurations of LiPSs, and quantify the corresponding adsorption energy. Furthermore, the intrinsic physical properties of Ti3C2T2 MXene and the reaction energy barriers that catalyze the conversion of LiPSs were investigated. These findings provide a valuable insight into the catalytic mechanism of MXene for LiPSs conversion.

Polyacrylonitrile (PAN) and thermoplastic polyurethane (TPU) were used as sacrificial polymer chaperone adhesives to prepare porous flexible free-standing electrodes. The prepared electrode has excellent flexibility, and the surface porous structure realizes porous channels for electrolyte, which fully ensures the infiltration of electrolyte in the electrode, so that the electrochemical performance is comparable to that of a conventional coated electrode. Ketjen black carbon (abbreviated KB) and carbon nanofibers (CNF) offer a good electronic conductive network in this electrode, while PAN forms a free-standing skeleton and TPU provides flexible components and sacrificial templates. The method utilized is universal for commercial electrode materials and has excellent practical value. The prepared electrode has an area density of more than 10 mg cm- 2 (20 mg cm-2 can be achieved by adjusting the slurry ratio), which is equivalent to the area density of current commercial coating electrodes. The electrode with NCM523 as active material exhibits the same electrochemical performance as traditional coated electrodes, deliver a high charge capacity 150.0 mAh g- 1 (10.0 mg cm- 2 ) after 100 cycles at 0.2 C.

The proliferation of portable electronics has intensified the demand for high-energy-density, safe electronic devices. Lithium-sulfur batteries (LSBs) have emerged as a promising solution due to their high theoretical energy density (2600 Wh kg−1), abundant sulfur resources, and cost-effectiveness. However, several challenges, including the inherent low electrical conductivity of sulfur, sluggish reaction kinetics of lithium polysulfides (LiPSs), and the severe shuttle effect, hinder the commercialization of LSBs. MXene-based materials, known for their high conductivity, strong lithophilicity, and mechanical strength, offer potential solutions to these issues. This review summarizes recent advancements in the application of MXene materials in LSB components, including methods for synthesizing and modifying MXene surfaces. The impact of these modifications on the electrochemical performance of LSBs is discussed, with particular emphasis on how MXene composites can enhance the performance of both electrodes and separators. Additionally, the application of MXene in lithium sulfide (Li2S) cathodes is explored, highlighting both opportunities and challenges. By integrating MXene into LSB systems, this review contributes to advancing the development of high-performance, sustainable energy storage solutions.

Parasitic shuttle effects and sluggish kinetics severely limit the practical applications of lithium-sulfur (Li-S) batteries. Developing conducting catalysts with high catalytic activity is effective strategy to address such issues. Electronic engineering as tuning strategy can optimize the electronic structure and enhance the redox reaction kinetics. Herein, NiSe2-CoSe2 hollow microspheres with abundant heterogeneous interfaces were synthesized as sulfur cathode catalysts. DFT calculations show that heterostructure can promote electron redistribution and form built-in electric field (BIEF), which causes the directional transfer of electrons. Additionally, NiSe2-CoSe2 has optimized adsorption energy, which can effectively suppress shuttle effect. Meanwhile, electrochemical tests further confirmed bidirectional catalytic ability. Benefiting the merits, S/NiSe2-CoSe2-GO-CNF (S/NiCo-GN) achieved an initial discharge specific capacity of 1353.35 mAh g- 1 at 0.2C and stable 1000 cycles at 1C with a capacity decay rate of only 0.044 % per cycle. Moreover, S/NiCo-GN also achieved high areal capacity of 1.688 mAh cm-2 at 0.5C under high loading (-2.5 mg cm- 2) and lean electrolyte (-10 mu L mg- 1) conditions. The flexible pouch cell further demonstrated its high safety, good thermal stability, and robust mechanical stability. This work provides guiding methods for the design of efficient catalysts, which can contribute to the realisation of high-performance Li-S batteries.

The Li-CO2 battery represented an enticing energy storage/output system characterized by its high-specific energy capacity and simultaneously achieving CO2 fixation and conversion, which held significant promise in mitigating global warming and advancing toward carbon neutrality. Nonetheless, the current Li-CO2 battery's practical capacity and energy efficiency lagged behind traditional lithium-ion battery considerably, posing great challenges for practical applications and commercialization. This review comprehensively summarized recent advancements and prospective strategies aimed at enhancing the effectiveness of practical Li-CO2 battery, encompassing insights into the cycling reaction mechanisms, anode electrode protection, key interface optimization, electrolyte design, and cathode catalyst innovations. Furthermore, insights into the prospects and key obstacles that lay ahead in advancing the Li-CO2 battery toward practical applications were provided.

Silicon (Si) exhibits great potential as an anode material for high-energy-density Li-ion batteries (LIBs). However, its limited cycling performance hinders its large-scale application. Here, we demonstrated that controlling the depth of lithiation of Si@C particles could enhance its reversibility of structure, employing suitable binders could prevent fragmentation of electrodes, and optimizing the full-cell parameters could improve the interface stability. These strategies synergistically contributed to the enhanced cycling performance of 100%-Si@C anode battery with a specific energy density exceeding 380 Wh/kg. This study provides valuable insights into the lithiation mechanism of Si@C anodes and offers guidelines for the future design in developing 100%-Si battery.

Nowadays, lithium-ion batteries (LIBs) have held the dominant role in various electric energy storage devices. With the rapid development of new energy vehicles and large-scale energy storage fields, there is an urgent demand for high-energy LIBs. While anode materials are important for determining energy density, commercialized graphite cannot meet the requirement for high specific capacity, and silicon-based materials always suffer from poor cycle stability. High-entropy oxides (HEOs) are emerging as a new category of single-phase material consisting of multiple principal elements with equimolar or quasi-equimolar ratios. Due to the design flexibility and interaction between multiple functional elements, HEOs can display improved comprehensive properties as LIBs anodes, which is expected to be a potential solution for high-energy LIBs. Herein, this review provides an extensive overview of the recent progress of HEOs anode materials in LIBs. The electrochemical properties of three typical HEOs are summarized, the synthesis methods for HEOs are subsequently elaborated, and current lithium storage mechanisms are analyzed in detail. Finally, the modification strategies are offered for further research to promote the development of HEO anodes in LIBs, including composition manipulations and the enhancement of conversion kinetic. It is aimed to propose practical guidance for exploration of HEO anode materials in next-generation high-energy batteries.