Material Utilization Ratio Research Articles

Electrospun Multiscale Structured Nanofibers for Lithium‐Based Batteries

Abstract Electrospun is a unique technique for the fabrication of multiscale structured nanofibers (MSNFs), which can be used as functional units for improving the performance of lithium‐based batteries. This review systematically examines how MSNFs, including core–shell, hollow porous, multichannel, wire‐in‐tube, tube‐in‐tube, and hierarchical nanofibers, effectively improve battery performance as components in lithium‐based batteries. The application of aforementioned MSNFs and their chemical modification contributes to the development of lithium‐based batteries with high energy density and enhanced safety when used as electrodes, separators, and electrolytes. Specifically, MSNFs are used to derive electrodes and electrolytes that improve electron/ion transfer rates, increase the utilization ratio of active materials, suppress dendrite growth, and mitigate volume expansion, enabling fast and stable electrochemical reactions at the electrodes. Additionally, MSNFs‐derived separators, which feature more ion transport channels, exceptional mechanical properties, and the capability to inhibit thermal runaway, are also discussed. Finally, the challenges and prospective pathways for electrospun technology in the application of lithium‐based batteries are reviewed.

A review of near‐net shape forming by hot isostatic pressure technology

AbstractNear‐net shaping hot isostatic pressing (NNS‐HIP) forming process has the advantage of high material utilization ratio and good uniformity of billet microstructure. It is widely used to produce critical parts for harsh service environments in special fields such as aerospace and energy and chemical industry. This paper introduces the process characteristics and production flow of hot isostatic near‐net forming, the representative materials of hot isostatic near‐net forming, the development and application at home and abroad, and the micro‐ and macromodels of numerical simulation powder densification by HIP near‐net forming. Finally, the challenges and development trends of this technology are prospected, and corresponding countermeasures are put forward.

Mathematical model for footwear upper material consumption estimation

Appropriate material consumption estimation since the design phase for footwear fabrication is a vital issue as material costs account for a sizeable portion of the overall production cost of a pair of shoes. This paper presents a mathematical model to predict the calculation of footwear upper material consumption to improve the utilization ratio of materials through a suitable nesting map onto leather. The proposed model concentrates on the two-dimensional geometry of footwear components and the application of rich mathematical concepts. The model reflects the outlines of individual footwear components while determining the area using definite integral calculus. Five distinct rotational kinds are applied for component arrangements that correlate to the physiognomy of leather because nesting onto the leather is intractable. The simple concept of a minimal-area polygonal enclosure is applied to maximize material utilization with minimum waste. Finally, the model was verified for four consecutive Oxford footwear sizes by comparing actual upper material consumption with predicted upper material consumption. The noble contribution of this analysis is to use ImageJ software to compute upper material consumption in real case analysis through image processing techniques and separate estimation of wastes, especially the fourth waste. The results of the comparison study show that the proposed model can reduce average material requirements by 2.06 %. This minimization of waste could be beneficial in terms of economic and environmental sustainability. Therefore, this study can be applied to estimate more accurately the amount of upper material required for footwear fabrication and support better utilization of material in the footwear industry.

Enhancing the adaptability of a mining complex in a dynamic environment by utilizing the technology for the development of a man-made deposit with a mobile ore preparation complex

The paper deals with the issue of the development of man-made deposits of the bulk type, especially that formed during the development of iron ore deposits. An analysis of the actual state of man-made deposits was performed. Based on analysis the technology of man-made deposits mining was proposed. It involves the extraction of technogenic raw materials from the bulk and their separation according to quality characteristics using a mobile ore preparation complex. According to the proposed technology, the conditioned raw materials are sent to the processing place, and the empty rock is laid in layers in the created space. The parameters of the mining system were studied in the paper: the width of the excavator’s cut step is limited on the one hand by the unloading radius of the dragline, and on the other by the turning radius of the dump truck. A significant role is played by the raw material utilization ratio: the larger it is, the narrower the excavator cut step will be. The results of the research can be useful for design organizations and mining enterprises which implement resource-saving technologies.

Research on Topology Optimization Design of Truss Structure

Due to continuous advances in engineering technology and architecture, the use of truss structures is expanding. The design method of ideal truss structure is the main research topic of this paper. The topology optimization method is applied to a bridge design case study. The load and total material utilization ratio of each rod of triangular truss, arch truss and Pratt truss were determined by using structural mechanics solver. By comparing the stress and material consumption of the truss structure, it shows that the truss structure has advantages in stress and can be used in the truss construction of short-distance arch bridge. Truss is the basic unit of the topology optimization method of truss structure proposed in this study. By optimizing the topological shape of the truss, the ideal design of the whole structure is realized. While maintaining structural stiffness and stability, the technology can significantly reduce the weight and cost of the structure.

Multi-objective prediction and optimization of performance of three-layer latent heat storage unit based on intermittent charging and discharging strategies

An intermittent heat charging and discharging strategy is proposed for on-demand thermal utilization in a three-layer latent heat storage unit filled with nanoparticle-enhanced phase change materials. To optimize the utilization ratio of phase change materials, and the stored and released thermal exergy amounts, a multi-objective prediction and optimization methodology combining orthogonal experimental design, range and variance analyses, multi-nonlinear regression models, and non-dominated sorting genetic algorithm-II is introduced while considering the variables of nanoparticle concentration, heat transfer fluid velocity, and intermittent time interval. Results show that the time interval presents the most significant influence. Multi-nonlinear regression models for the above three variables are established with determination factors of 0.9871, 0.9625, and 0.9253, respectively. The ultimate optimal results are 0.8, 57094.03 J, and 43066.73 J, achieved at the three variables of 44.37 min, 0.38 m s−1 and 8.99%, respectively. The maximum verification error of 5.11% indicates the reliability of this methodology. The methodology aims to enhance the overall performance of the three-layer latent heat storage system by mitigating the constraints associated with single-performance optimization.

Flexural strengthening of timber-concrete composite beams using mechanically fastened and externally bonded combining mechanically fastened strengthening techniques

Timber-concrete composite (TCC) beams fail due to the tensile failure of the bottom timber lamellas, with the upper concrete remaining elastic, indicating a low utilization ratio of materials. Consequently, two types of strengthening techniques, namely mechanically fastened (MF) and externally bonded combining mechanically fastened (EB + MF), were used in this study to strengthen the TCC beams. Four-point bending tests were conducted to evaluate the strengthening efficiency of the MF and the EB + MF strengthening techniques for the TCC beams. Experimental variables include different strengthening techniques (MF, and EB + MF), types of reinforcement (steel and CFRP), and thickness of reinforcement. The test results indicate that the ultimate load capacity of the TCC beams was significantly improved, with a maximum improvement of up to 85.4% for the EB + MF and 30.6% for the MF strengthening techniques, respectively. The MF and the EB + MF strengthening techniques improved the bending stiffness of the TCC beams ranging from 10.8% to 41.6%. Generally, the MF strengthening technique shows a slightly lower strengthening efficiency in ultimate load capacity and bending stiffness compared with the EB + MF strengthening technique, respectively, indicating that the MF strengthening technique is also an effective way for strengthening the TCC beams. The comparison between the experimental and calculated bending stiffness indicates that the γ method reported in Eurocode 5 underestimates the bending stiffness by 40% on average for all the tested TCC beams.

Utilization Ratio of Active Materials in All-Solid-State Batteries Examined Using Electrochemical Impedance Analysis with the Transmission Line Model

In all-solid-state batteries (ASSB), increasing the thickness of electrodes is essential for increasing the energy density. However, this limits the C-rate performance, particularly for electrodes with a large volume fraction of active materials (AMs), transport of ions in the electrode is hindered, leading to poor utilization of AMs in ASSBs. To accelerate the development of ASSBs, it is highly desirable to develop analytical methods for understanding the utilization of AMs in thick electrodes. In this paper, we propose a novel impedance analysis method using the transmission line model (TLM) for estimating the utilization of AMs in an electrode in terms of effective electrode thickness. In the TLM model, electrode thickness is treated as a variable instead of a fixed parameter in the conventional sequence. Hence, the modified C-rate performance considering the TLM-calculated thickness exhibits an identical trend regardless of the actual electrode thickness, suggesting the calculated electrode thickness reflects the effective electrode thickness. This indicates effective utilization of AMs for electrochemical reactions. We also demonstrate the versatility of this method by using different electrode specifications.

Synergistic effect of Li2S@Li3PS4 nanosheets and MXene for high performance lithium-sulfur batteries

Lithium sulfide (Li2S) is a promising cathode material for Lithium-sulfur (Li–S) batteries, but poor conductivity and electrochemical reactivity seriously hinders its applications. Herein, Ti3C2 nanosheet (TNS) supported core-shell nano-Li2S@Li3PS4 composite (NLi2S@LPS) is comprehensively designed to tackle these challenges. It displays fast Li+/e− transport kinetics, low energy barrier and high catalytic activity for the electrochemical redox reactions, which are derived from the synergistic effect of nano-sized Li2S, Li3PS4 coating and catalytic MXene (Ti3C2) components. The NLi2S@LPS/TNS composite electrode exhibits high utilization ratio of the active materials with low polarization and robust rate capability for charge/discharge, resulting in improved cycling stability for Li–S batteries. The Li–S batteries with NLi2S@LPS/TNS electrode have a capacity retention rate of 77% after 300 cycles of charge and discharge at 0.5C rate, corresponding to an average decay rate of 0.08% per cycle.

Oxygen defect-mediated NiCo2O4 nanosheets as the electrode for pseudocapacitors with improved rate capability.

Transition metal oxide-based supercapacitors have attracted much attention due to their high theoretical specific capacitances. However, due to an insufficient utilization ratio and poor intrinsic conductivity of active materials, the rate performance of these electrodes is usually low. Herein, oxygen defect-mediated NiCo2O4 nanosheets with enhanced electrical conductivity (1.9 S m-1vs. 0.2 S m-1 of original NiCo2O4 NSs) are fabricated using a post NaBH4 reduction strategy (denoted as r-NiCo2O4 NSs). The derived r-NiCo2O4 materials have sheet-like morphology, increased oxygen defects and low valence metal species, and an unprecedented rate capability comparable to that of carbon-based electrode materials, with a satisfactory capacitance of 1812 F g-1 and 91.5% retention at 20 A g-1. The general strategy can be extended to other transition metal oxides to construct enhanced conductivity electrodes for related energy storage and conversion devices.

Experimental and numerical studies on hysteretic behavior of a novel bending-friction coupled damper

A novel bending-friction coupled damper (BFCD), capable of providing stable energy dissipation and improved stiffness against multi-level earthquakes, is proposed in the present study. To investigate the influences of loading protocols and configurations of bending bars on the hysteretic behavior of the BFCD, quasi-static tests were conducted on one conventional friction damper and five BFCD specimens. Three processes during each loading cycle, i.e., the static friction process, the sliding friction process and the coupled working process, were clearly reflected by the test hysteretic curves. Attributed to the adoption of bending bars, the maximum forces of all specimens increased by 98.0%–153.7% compared with the sliding friction forces. The BFCDs adopting linear-shaped bending bars presented higher strength, stiffness and energy dissipation compared with those adopting the partially weakened bending bars. The cumulative energy dissipation per volume of partially weakened bending bars with a slightly weakened diameter was 31.8% larger than that of linear-shaped bars, which showed a higher material utilization ratio. In addition, finite element models of BFCDs were established and validated. Configuration improvements were conducted to achieve a more stable and controllable behavior of the BFCD. Numerical parametric analyses based on the improved BFCD model confirmed that the strength, stiffness and the activation sequence of two damping parts could be effectively controlled through reasonable design.

Coordination-derived nickel cobalt sulfide solid microspheres with surface defects for high-performance asymmetric supercapacitors

Bimetallic sulfides are effective cathode materials for asymmetric supercapacitors because of their excellent electrochemical properties. However, both the low utilization ratio of the electrode material and the low energy storage capacity have restricted further development. In this work, Ni and Co were reacted with terephthalic acid (H2BDC) and isonicotinic acid (Ina) under hydrothermal conditions, followed by hydrolysis in 1 M KOH and vulcanization in thiourea to yield nickel cobalt sulfide (CoNi2S4) solid microspheres (NiCoS) with surface defects consisting of bumps and holes. These structural and morphological features compensate for the shortcomings of bimetallic sulfide electrodes, enhance their energy storage capacity, and improve their capacitance performance. The specific capacitance of the asymmetric supercapacitor assembled with NiCoS and a self-made carbon electrode reached 168.0 and 101.6 F/g at specific currents of 1 and 20 A/g, respectively. An increase in the specific current by a factor of 20 corresponded to an increase in capacitance retention rate to 60.5%, improving the rate performance. When the specific power increased to 800 and 16 000 W/kg, the specific energy reached 59.7 and 36.2 Wh/kg, respectively. Following 5,000 charge/discharge cycles, the capacitance retention rate was 96.78%. Such excellent comprehensive electrochemical performance greatly increases the competitiveness of the NiCoS electrode in the field of electrochemical energy storage.

(Digital Presentation) Accelerating the Conversion Process of Polysulfides in High Mass Loading Sulfur Cathode for the Longevity Li-S Battery

Conventional lithium-ion batteries are unable to meet the increasing demands for high-energy storage systems, because of their limited theoretical capacity.1 In recent years, intensive attention has been paid to enhancing battery energy storage capability to satisfy the increasing energy demand in modern society and reduce the average energy capacity cost. Among the candidates for next generation high energy storage systems, the lithium sulfur battery is especially attractive because of its high theoretical specific energy (around 2600 W h kg-1) and potential cost reduction. In addition, sulfur is a cost effective and environmentally friendly material due to its abundance and low-toxicity. 2 Despite all of these advantages, the practical application of lithium sulfur batteries to date has been hindered by a series of obstacles, including low active material loading, poor cycle life, and sluggish sulfur conversion kinetics.3 Achieving high mass loading cathode in the traditional 2D planar thick electrode has been challenged. The high distorsion of the traditional planar thick electrodes for ion/electron transfer leads to the limited utilization of active materials and high resistance, which eventually results in restricted energy density and accelerated electrode failure.4 Furthermore, of the electrolyte to pores in the cathode and utilization ratio of active materials. Catalysts such as MnO2 and Co dopants were employed to accelerate the sulfur conversion reaction during the charge and discharge process.5 However, catalysts based on transition metals suffer from poor electronic conductivity. Other catalysts such as transition metal dopants are also limited due to the increased process complexities. . In addition, the severe shuttle effects in Li-S batteries may lead to fast failures of the battery. Constructing a protection layer on the separator for limiting the transmission of soluble polysulfides is considered an effective way to eliminate the shuttle phenomenon. However, the soluble sulfides still can largely dissolve around the cathode side causing the sluggish reaction condition for sulfur conversion.5 To mitigate the issues above, herein we demonstrate a novel sulfur electrode design strategy enabled by additive manufacturing and oxidative vapor deposition (oCVD). Specifically, the electrode is strategically designed into a hierarchal hollow structure via stereolithography technique to increase sulfur usage. The active material concentration loaded to the battery cathode is controlled precisely during 3D printing by adjusting the number of printed layers. Owing to its freedom in geometry and structure, the suggested design is expected to improve the Li ions and electron transport rate considerably, and hence, the battery power density. The printed cathode is sintered at 700 °C at N2 atmosphere to achieve carbonization of the cathode during which intrinsic carbon defects (e.g., pentagon carbon) as catalytic defect sites are in-situ generated on the cathode. The intrinsic carbon defects equipped with adequate electronic conductivity. The sintered 3D cathode is then transferred to the oCVD chamber for depositing a thin PEDOT layer as a protection layer to restrict dissolutions of sulfur compounds in the cathode. Density functional theory calculation reveals the electronic state variance between the structures with and without defects, the structure with defects demonstrates the higher kinetic condition for sulfur conversion. To further identify the favorable reaction dynamic process, the in-situ XRD is used to characterize the transformation between soluble and insoluble polysulfides, which is the main barrier in the charge and discharge process of Li-S batteries. The results show the oCVD coated 3D printed sulfur cathode exhibits a much higher kinetic process for sulfur conversion, which benefits from the highly tailored hierarchal hollow structure and the defects engineering on the cathode. Further, the oCVD coated 3D printed sulfur cathode also demonstrates higher stability during long cycling enabled by the oCVD PEDOT protection layer, which is verified by an absorption energy calculation of polysulfides at PEDOT. Such modeling and analysis help to elucidate the fundamental mechanisms that govern cathode performance and degradation in Li-S batteries. The current study also provides design strategies for the sulfur cathode as well as selection approaches to novel battery systems.

Tunable In-series Laser Array With Duplex Distributed Feedback Sections

The tunable laser based on distributed feedback (DFB) laser array has a good single-longitudinal-mode property, high wavelength stability, narrow spectrum linewidth, and feasibility for monolithic integration. The tunable in-series DFB laser array (TIDLA) was proposed to avoid the large extra power loss by the optical combiner. But in the TIDLA, a large laser count will cause a large chip length, which brings about low utilization ratio of material, poor mechanical strength, and large power consumption. In this paper, we demonstrated a 4-channel TIDLA with duplex DFB sections. The total chip length was greatly shortened owing the duplexing of DFB sections. A long linearly chirped Bragg grating is implemented in the laser cavity to reduce the grating interference among different lasers. Multiple π phase shifts and two reflector sections are introduced to improve the mode stability. The designed channel spacing is 100 GHz, and the reconstruction-equivalent-chirp technique is used to provide high precision control of the grating phase. Noted that a variation of 0.1 nm in grating period will cause that of 0.65 nm in wavelength. Output power of above 4 mW, SMSR of above 42 dB, and small wavelength deviation of within 0.15 nm was obtained. Besides, fast channel switches of less than 1 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> s are obtained by laser on/off switching. The proposed TIDLA might be applied in the NG-PON2 network where the dense wavelength division multiplexing technique and fast channel switching are required.

Highly Sensitive Detection of Carcinoembryonic Antigen via an Electrochemical Platform Fabricated by AuNPs/Streptavidin/Reduced Graphene Oxide.

Tumor markers are one of the important indicators for early cancer diagnosis. As a new analytical method, electrochemical immunosensing analysis has the advantages of high sensitivity, good selectivity, and rapid detection, which is of great significance for the detection of tumor markers. In this work, an AuNP/reduced graphene oxide (AuNP/rGO) composite was synthesized. We used it for electrochemical sensor fabrication with the assistance of the biotin–streptavidin protein (SA) system to further amplify the signal to achieve sensitive detection of carcinoembryonic antigen (CEA). In addition, AuNPs have been incorporated due to their good electrical conductivity and biocompatibility, which can accelerate electron transfer at the electrode interface and improve the loading capacity to capture antibodies. The fabricated AuNPs/SA/rGO has a large working surface area and high material utilization ratio, which improves the catalytic capacity of H2O2 reduction and effectively amplifies the current signal. The linear range of the response current signal of the sensor toward the CEA concentration is 20 fg/ml to 200 ng/ml, and the limit of detection can achieve 6.2 fg/ml. In addition, the fabricated immunosensor has good reproducibility, selectivity, and stability.

A periodic dissipative system with self-locking capacity

Periodic systems derive the excellent energy absorption capacity mainly from their inner basic elements. However, lateral spattering of these basic elements frequently occurs in unconstrained dissipative systems under compression or impact load, which drastically reduces their energy absorption efficiency. A self-locking periodic system composed of corrugated tubes that can suppress lateral splashing is proposed to overcome this limitation. These inner corrugated tubes are able to firmly interlock with neighboring columns without any additional constraints, thus achieving the desired self-locking effect. The force-displacement relationship of the inner corrugated tube is solved for the overall compression process based on a plastic hinge model, which is verified by compression test. It is proved that corrugated tubes exhibit excellent characteristics, such as high material utilization ratio and high specific energy absorption. Compression and impact tests are also conducted to validate the self-locking effect of the entire corrugated system. The effects of key geometrical parameters, such as wall thickness, inclination angle and connection plate width, are systematically investigated. Taking both high-performance basic elements and valid constraints into consideration can achieve the optimal specific energy absorption and provide a new strategy for developing energy absorption metamaterials.

Universal low-temperature and template-free synthesis of sponge-like porous micron-sized elemental materials for high-performance lithium/potassium storage

Interconnected porous micron-sized materials can effectively enhance the ion transfer kinetics and structural stability, thus improving their rate capability and long-term lifespan, and maintaining high volumetric performance, but developing a universal and low-temperature method for the large-scale synthesis of porous materials remains a formidable challenge. Herein, we develop a universal low-temperature and template-free strategy to fabricate a series of sponge-like, interconnected porous micron-sized elements (e.g., Se, Te, Sb) through H2O2-assisted water bath. The formation mechanism of porous structure is demonstrated, originating from the non-homogeneous and continuous corrosion due to the preferential intergranular corrosion of polycrystalline particles and the soluble reaction products that do not passivate the corrosion interface. The as-obtained sponge-like porous elements present large reversible gravimetric and volumetric capacities and long stable lifespans. Specifically, the porous Te electrode delivers a high reversible capacity of 392.7 mAh g−1 (volumetric capacity: 1531.5 mAh cm−3) with 93.5% utilization ratio of active materials at 0.1 A g−1 and a long-stable lifespan with 500 cycles at 1.0 A g−1 in Li-Te batteries. Besides, in-situ TEM and ex-situ SEM observations demonstrate a small volume expansion and strong structural robustness of porous Te during cycling, stemming from its inward expansion mechanism and 3D stable interconnected porous structure. This work demonstrates a simple and universal strategy to design sponge-like porous materials for energy storage and catalysis, etc.

Research on the Impact of Recycled Asphalt Mixture on Road Performance Based on New Thermal Recycling

Different binder content to RAP Regeneration SBS modified asphalt mixture for road performance to SBS modified asphalt (I-D type) as an index, determine the optimum dose of new heat regenerating agent and different RAP regeneration, and prepared different recycled asphalt, which have differences in RAP content. The performance of recycled asphalt mixture with different RAP content was evaluated by freeze-thaw splitting test. Rut test and Low temperature trabecular bending test. The correlation between RAP content and pavement performance was analyzed by grey system correlation analysis method. According to the experimental verification results, it can be known that increasing the content of RAP material can improve the high-temperature performance of reclaimed asphalt, but will result in a qualitative decrease in low-temperature performance and water temperature, but the above-mentioned performance can reach the required level, Shows that new heat regenerators play a role in the road performance of RAP materials, and for the RAP material utilization ratio of more than 50%, as for the gray correlation analysis, it can be found that there is a close correlation between the low-temperature performance of recycled asphalt mixture and the content of RAP material. The low temperature cracking resistance of asphalt mixtures will change significantly due to the slight changes in RAP materials.

Methods of controlling electrochemical energy storages: classification and application features

Energy storages are the most important integral elements of both autonomous energy system based on renewable energy sources and vehicles of various purposes, where they are the main power source. Therefore, the issue of controlling their operation modes is an important one, and choosing the control methods is a relevant problem. The main operation modes of energy storages which require controlling are the work mode when the stored energy is consumed and the charging mode when the used energy is replenished. The example of on-vehicle energy storage is used to analyze basic operation modes and their particular aspects. Dynamic modes with unpredictable energy consumption caused by uncontrollable undercharging and overcharging are typical. The analysis allowed drawing the conclusion that, when controlling operation modes, it is necessary to consider the energy modes of accumulators, which reflect its efficiency most fully and objectively. The analysis of existing control methods showed that their common disadvantage is that they use such parameters as voltage and operating current to control and manage the storage modes. The fact is that due to the transient nature of electrochemical processes during the operation of the storage in dynamic modes, the values of these parameters do not correspond to the current energy state of the storage. This study aims to increase the performance of electrochemical energy storages by efficiently choosing a method for controlling their operation modes. The authors prove and experimentally confirm that when working with electrochemical energy storage devices in dynamic modes, it is necessary to choose the methods based on the application of the active material utilization ratio, information equivalent of which is the value of the area under the depolarization curve on the storage’s response signal to the charging impulse. The use of the proposed mode allows combining the functions of controlling and managing the storage.

Phosphorus-doped carbon sheets decorated with SeS2 as a cathode for aqueous Zn-SeS2 battery

SeS 2 @PCS exhibits high performance as cathode for aqueous Zn batteries based on the reversible conversion of SeS 2 to ZnSe and ZnS with I 2 as redox-mediator. • SeS 2 @PCS is firstly proposed as a conversional cathode for aqueous Zn batteries. • Electrolyte additive enhances the electrochemistry of SeS 2 @PCS. • SeS 2 @PCS exhibits ultrahigh energy density and excellent cycling. • Reversible conversion from SeS 2 to ZnSe and ZnS is demonstrated. • DFT calculations reveal the critical role of electrolyte additive. Intrinsically limited by the high dependence on the host framework structure, aqueous Zn-based batteries built on intercalated cathodes suffer unsatisfactory energy density. In this work, phosphorus-doped carbon sheets (PCS) encapsulated SeS 2 (SeS 2 @PCS) is proposed as a conversional cathode for aqueous Zn-SeS 2 battery. In the electrolyte of 1 M ZnSO 4 with I 2 as additive, the electrochemical performance of SeS 2 @PCS can be remarkably boosted. It delivers a reversible capacity of 1107 mAh g −1 with a flat discharge potential of 0.74 V (versus Zn 2+ /Zn) and small polarization of 0.41 V, corresponding to energy density up to 772 Wh kg −1 (based on SeS 2 ), which is one of the highest values reported in aqueous Zn-based batteries in mild electrolyte, and keeps a capacity retention of 85% after 1000 cycles. Moreover, the reaction mechanisms are demonstrated to be the reversible conversion between SeS 2 to ZnSe and ZnS. Experimental and theoretical calculations reveal that I 2 can function as redox mediator to enhance the reversible capacity and kinetics due to the improvement of material utilization ratio, electrode/electrolyte interface compatibility and adsorption of Zn 2+ ions. This work presents the design of high performance conversional cathodes and strategy to improve the kinetics for aqueous Zn-based batteries.