Large Storage Devices Research Articles

Magnetic field based finite element method for magneto-static problems with discontinuous electric potential distributions

We introduce two finite element formulations to approximate magneto-static problems with discontinuous electric potential based respectively on the electrical scalar potential and the magnetic field. This work is motivated by our interest in Liquid Metal Batteries (LMBs), a promising technology for storing intermittent renewable sources of energy in large scale energy storage devices. LMBs consist of three liquid layers stably stratified and immiscible, with a light liquid metal on top (negative electrode), a molten salt in the middle (electrolyte) and a heavier liquid metal on bottom (positive electrode). Energy is stored in electrical potential differences that can be modeled as jumps at each electrode-electrolyte interface. This paper focuses on introducing new finite element methods for computing current and potential distributions, which account for internal voltage jumps in liquid metal batteries. Two different formulations that use as primary unknowns the electrical potential and magnetic field, respectively, are presented. We validate them using various manufactured test cases, and discuss their applications for simulating the current distribution during the discharge phase in a liquid metal battery.

Hyper-conjugated polyaniline delivering extraordinary electrical and electrochemical properties in supercapacitors

Conjugated polymers promise extremely-high theoretical supercapacitance to develop large capacitive storage devices. Existing conjugated polymers commonly realize their < 20% supercapacitance due to inferior electronic and electrochemical activities. Here we report hyper-conjugated effect to minimize energy level difference and carrier migration barrier in copolymerized polyaniline (PANI), a typical supercapacitive material. The hyper-conjugated effect efficiently promotes the elongation of conjugation system and the delocalization of π electrons. The largely increased number of free carriers in combination with the expanded range of carrier mobility guarantee 800% increments in electrical conductivity. Tests of symmetric supercapacitors with hyper-conjugated PANI show a high specific capacitance of 512 F g−1, excellent rate-capability and long-term cyclability. This work paves the way for designing conjugated polymers with remarkable electronic and electrochemical properties.

Chronic Kidney Diseases Detection Using machine Learning

Chronic kidney disease (CKD) and chronic renal disease (CRD) (CKD). Chronic renal disease refers to illnesses that affect your kidneys and reduce their ability to keep you healthy. Consequences include nerve damage, high blood pressure, anaemia, weak bones, and a lack of nourishment. Early detection and treatment can frequently stop chronic renal disease from getting worse. Data mining is the technique of obtaining knowledge from huge datasets. Utilizing previous data to find trends and guide decisions going forward is the aim of data mining. This task is the result of the convergence of a number of recent trends, including the declining cost of large data storage devices, the increasing simplicity of data collection over networks, the expansion of dependable and efficient machine learning algorithms, and the declining cost of computational power, which enables the use of computationally intensive techniques for decision-making. Machine learning has already produced useful applications in fields like assessing results from medical research, spotting fraud, spotting bogus users, etc.For the purpose of predicting chronic diseases, various data mining categorization methodologies and machine learning algorithms are used. The goal of this study is to develop a new decision-support system for forecasting chronic renal disease. This study compares the accuracy, precision, and execution time of Support Vector Machine (SVM) and K-Nearest Neighbor (KNN) classifiers for the prediction of CKD.

Fe7Se8 nanoparticles encapsulated by CNT reinforced fibrous network with advanced sodium ion storage and hydrogen evolution reaction

Sodium ion batteries (SIBs) has been regarded as one of the most promising large scale energy storage devices. Besides, hydrogen production by water splitting is the green, safe and low cost long-term energy conversion and storage technology. Rare studies have reported advanced electrode materials for both SIBs and HER. Herein, Fe7Se8 nanoparticles have been successfully encapsulated into CNT reinforced fibrous network (Fe7Se8/CNT/C) by electrospinning combined with in situ selenide process. When utilized as flexible anodes for SIB, the Fe7Se8/CNT/C delivers superior rate capabilities (524 mAh g−1 even at 5000 mA g−1) and cycling stability (610 mAh g−1 at 500 mA g−1 after 1000 cycles). Moreover, the Fe7Se8/CNT/C also delivers considerable hydrogen evolution reaction (HER) activity (an overpotential of 138 mV at a current density of 10 mA cm−2 and a Tafel slope of 114 mv dec−1). Ex-situ electrochemical mechanism studies including EIS, GITT, CV and ECSA reveal that the graphitized CNT reinforced fibers can accelerate the ions/electrons transportations and the robust fibrous network structure guarantees excellent structural stability, thereby, preventing the aggregations of Fe7Se8 nanoparticles, facilitating electrolyte penetration and creating numerous catalytic active sites. Therefore, the Fe7Se8/CNT/C is one of the most promising energy storage and conversion materials. The fabrication strategy in this work could give an insight in exploring advanced functional materials.

Aqueous proton batteries based on acetic acid solutions: mechanistic insights

Large grid energy storage devices are critical for the success of the clean and sustainable energy revolution. As Li-ion batteries are earmarked for electric vehicles and portable devices such as laptops and cellphones, other electrochemical systems should be developed that enable cost-effective, safe, and durable large-scale energy storage. Due to the low cost and non-flammability of aqueous electrolyte solutions, much effort is being put into the development of ‘beyond-Li’ batteries and super capacitors that can work in these environments. Here, we propose new proton batteries comprising an acetic acid electrolyte solution, NiII [FeIII(CN)6]2/3·4H2O Prussian blue analog cathodes, and Ti3C2Tx MXene anodes. Both electrodes were investigated independently to discover ideal settings for the electrochemical performance and stability. Significant attention was given to the cathodes' protons storage mechanism. In-situ electrochemical quartz crystal microbalance with dissipation revealed that in acetic acid, hydronium and proton insertion contribute to charge storage, whereas in sulfuric acid-based electrolyte solutions, the main charge carriers are bare protons. 4.5 M acetic acid solution provided the best performance in terms of electrodes' capacitance and rate capability. The battery systems presented here show a promising direction but require further intensive optimization efforts. This research opens the way for research and development of novel proton batteries based on solutions containing common weak acids for more cost-effective and environmentally friendly energy storage systems.

Comparative Study on the Electrochemical Properties of Cylindrical and Pouch-Type Lithium Ion Battery

As the field expands from portable electronic devices to large energy storage devices such as electric vehicles, more reliable and innovative battery technologies are more important than ever.Currently, there are three types of lithium battery packaging: cylindrical, prismatic and pouch. Cylindrical batteries with a cylindrical shape and structure were one of the first mass-produced battery types and are still mass-produced and dominate in some applications. On the other hand, prismatic batteries are gaining popularity due to their high capacity, thin form, and efficient use of space. Due to the angular shape, multiple cells can be easily connected to form larger packs. Finally, pouch batteries are known for their lighter construction, using a sealed flexible foil as the packaging material.Each of these battery types offers a set of advantages and disadvantages. There is no clear winner, but the battery you choose can influence your product design in many ways. For example, each of these battery form factors can have a different temperature distribution and heat transfer model.In this study, a cylindrical battery and a pouch-type battery of the same capacity were manufactured using the same four major materials (positive electrode, negative electrode, separator, and electrolyte), respectively, to study the cell chemical characteristics of Li-ion secondary batteries. In particular, it is intended to provide a field to which each type of lithium ion secondary battery can be applied by understanding the characteristics of thermal and deterioration.

Water enables a performance jump of glass anode for lithium-ion batteries

It is known that some oxide glass systems are a promising class of anode materials for lithium-ion Batteries (LIBs). However, the relatively low capacities of glass anodes severely limit their practical application for large energy storage devices. In this work, we establish an unconventional approach, by which the electrochemical performances of glass anodes for LIBs can be considerably enhanced. Specifically, we incorporate water into an electrochemically active glass system, i.e., TeO2-V2O5-P2O5 (TVP) glass powder via humidity treatment, and then mix the hydrated powder with additives to fabricate anode for LIBs. The optimized humidity treatment leads to the structural modification of the TVP glass powder, which boosts the lithium ion storage capacity of the TVP anode by more than 2.4 times, and maintains the reversible capacity for extra-long cycles. The boosted performances are attributed to both the depolymerized structural network for Li+ diffusion and the hydration-induced nanocrystals. These findings help develop superior glass electrodes in an economically effective way.

In Situ Defect‐Free Vertically Aligned Layered Double Hydroxide Composite Membrane for High Areal Capacity and Long‐Cycle Zinc‐Based Flow Battery

AbstractRechargeable aqueous zinc‐based flow batteries (ZFBs) are promising candidates for large scale energy storage devices. However, the challenges from zinc dendrites and limited areal capacity considerably impede their wide application. Here, an in situ vertical growth of layered double hydroxide membrane (LDH‐G) is constructed to enable long‐life ZFBs. Owing to the high hydroxide ion conductivity and ion selectivity nature of LDH nanosheets, specifically, the precise control of directional ion transport in vertical arrangement LDHs, a superior battery performance can be realized. Moreover, the defect‐free LDHs layer serves as a buffer layer to enable a uniform Zn deposition, which effectively enhances the areal capacity of the battery. As a result, the designed membrane endows an alkaline zinc‐iron flow battery with excellent rate performance and cycling stability, maintaining an energy efficiency of 80% at 260 mA cm−2 for 800 cycles, which is the highest performance ever reported. Most importantly, the LDHs layer enables the battery for 1200 h long‐cycle stability with a uniform Zn deposition and high areal capacity of 240 mAh cm−2. This work realizes an in situ growth of 3D LDHs arrays on the polymer substrate, which provides a strategy toward high areal capacity and dendrite‐free Zn deposition for ZFBs.

(Invited) Stress Evolution on the Solid Electrolyte in Lower Temperature Operating Planar Sodium Nickel Chloride Batteries

Sodium nickel chloride (Na-NiCl2) battery is one of the most promising candidates as a large scale electrochemical energy storage device since it offers high safety, long lifetime, and high energy density. The battery comprises molten metallic Na and NiCl2 as negative and positive electrodes, respectively, separating them by a β”-Al2O3–family solid electrolyte (BASE). In order to facilitate fast sodium-ion transport in the cathode compartment, the battery typically operates at 300oC accompanying with molten NaAlCl4 (catholyte), which is infiltrated into the cathode materials powder. A drawback of the efficient battery hampering broader market penetration is high manufacturing cost as it adopts expensive heterogeneous sealing technologies, such as thermal compression bonding, glass sealing, and laser beam welding, which are inevitable to withstand its high operating temperature. However, when lowering the operating temperature down to below 200oC, inexpensive polymer can be introduced replacing all the expensive sealing technologies, through which cell manufacturing process can be substantially simplified at the same time.In developing the lower temperature operating planar Na-NiCl2 battery, one of the major cell failure modes is mechanical failure in solid electrolytes either by thermal stress accumulation upon freeze-thaw cycles or by stresses developed by pressure difference between cathode and anode compartments during charge-discharge cycles. The presentation will start with defining failure modes of this new class of Na beta-alumina battery with special emphasis on electrolyte failure. In order to understand the stress accumulation in the vicinity of the solid electrolyte, a set of finite element analyses (FEA) has been conducted for various simulated conditions. It turns out that (1) sealing temperature, and (2) inner volumes of cathode and anode compartments need to be carefully designed to avoid the mechanical failure. The results of the calculation and cell design strategy for this novel battery will be discussed. Figure 1

Abundant Natural Dye-Based Organic Molecule As Sole Redox Active Material for Symmetric Aqueous Redox Flow Battery

Organic redox flow batteries (ORFBs) are considered potential substitutes to their traditional metal-based counterparts for application as large scale energy storage device[1] . This is in consideration to the merits offered by organic redox active materials i.e. inexpensive, environment friendly, high solubility and existence in diverse molecular structures that facilitates synthetic tunability to design molecules with the desired physicochemical properties[2] . However, capacity fade as result of cross-contamination has been one of the main challenges hindering development of this energy storage technology[3] . Symmetric redox flow batteries that employs a single redox active material in both electrolytes have the potential to address this challenge making them very attractive[4] .In this work, a low-cost organic dye is coupled with a radical organic molecule to form a sole bifunctional redox active material that can be used as both negoyte (-0.71V) and posolyte (0.52V versus Hg/Hg2SO4) in an organic symmetric aqueous redox flow battery. Cyclic voltammetry studies of the combined bifunctional molecule reveal reversible redox reactions of the redox couples leading to a theoretical cell voltage of 1.23V. A symmetric pumped cell testing demonstrated over 100 consecutive charge/discharge cycles with nearly 85% coulombic efficiency at current density of 2.5 mAcm-2. The battery utilizes a pH neutral supporting electrolyte (NaCl in water) which is inexpensive, non-corrosive and non-flammable resulting to a low-cost, durable, safe and environmental-friendly redox flow battery.

Electrolyte additives: Adding the stability of lithium metal anodes

AbstractLithium metal is regarded as the “holy grail” of anodes due to its highest theoretical specific capacity and lowest electrode potential, and hence is considered as a promising anode candidate to meet the growing demand for large scale energy storage devices. However, lithium metal anode is suffering the challenges in side reactions, volume change, and low Coulombic efficiency, and particularly the growth of lithium dendrites, which extremely limits its practical applications. To tackle these issues, many strategies have been developed. Among them, the addition of electrolyte additives is an effective and the simplest method. In this review, electrolyte additives for enhancing the stability of Li metal anodes are summarized, according to their different working mechanisms. The prospects of key challenges and future trends of such electrolyte additives are discussed.

Penggunaan Deteksi Gerak untuk Pengurangan Ukuran Data Rekaman Video Kamera CCTV

Some cases the recording data of Closed Circuit Television (CCTV) is stored for future use. In the long term usage, the files size will grow larger and requiring large storage devices. In some cases, the recorded data not only image with the desired object but also the background images that may be recorded for long periods of time. This cases make data storage device usage to be less effective. So this research will design a system of CCTV devices that capable to select images to reduce the size of stored images data by image processing.The images selection of this system is based on based on adaptive median algorithm. When any object get detected, the images data to be saved is current input frame. Otherwise, the data to be saved is background model image. Background model on this system is adapted with the change visual data of background image.The results obtained from this research in the form of a CCTV system that are able to select recording data to be stored with image processing. The background model will be kept adapting with background visual data changes.

Compression and encryption for ECG biomedical signal in healthcare system

The ECG data needs large memory storage device due to continuous heart rate logs and vital parameter storage. Thus, efficient compression schemes are applied to it before sending it to the telemedicine center for monitoring and analysis. Proper compression mechanisms can not only improve the storage efficiency but also help in faster porting of data from one device to another due to its compact size. Also, the collected ECG signals are processed through various filtering techniques to remove unnecessary noise and then compressed. In our scheme, we propose use of buffer blocks, which is quite novel in this field. Usage of highly efficient methods for peak detection, noise removal, compression and encryption enable seamless and secure transmission of ECG signal from sensor to the monitor. This work further makes use of AES 256 CBC mode, which is barely used in embedded devices, proves to be very strong and efficient in ciphering of the information. The PRD outcome of proposed work comes as 0.41% and CR as 0.35%, which is quite better than existing schemes. Experimental results prove the efficiency of proposed schemes on five distinct signal records from MIT-BIH arrhythmia datasets.

Construction of binder-free hierarchical mesoporous 3D Co–Mo–O flowers assembled by nanosheets for aqueous symmetrical 1.2 V supercapacitor in basic electrolyte

Aqueous symmetrical supercapacitors (ASSCs) are offering the safest and cost-effective solution to fulfill the ever-increasing demand for high-performance energy storage devices. However, the narrow operational voltage window in basic electrolytes is significantly limits their practical applications. Herein, we demonstrate a high-voltage ASSCs in a basic electrolyte by combining the binder-free highly Faradic-type cobalt and highly capacitive-type molybdenum oxides with rich oxidation/reduction states. The electrochemical performance of mesoporous cobalt-molybdenum oxide supported on carbon cloth (Co–Mo–O@CC) are first optimized in three electrode-system and it reveals high-capacitance of 1437.5 F g−1 (862.5 C g−1) at 1.5 A g−1 with outstanding rate-capability (81.19%) and cycling stability (95%) over 8000 cycles. Moreover, the fabricated ASSC based on the Co–Mo–O@CC electrodes (CMO||CMO-ASSC) is delivered admirable performance by exhibiting the high-capacitance of 180.5 F g−1 (2.63 F cm−2) at 1.0 A g−1 with good rate capability of 72.34% at high current density of 8 A g−1 as well as decent capacitance retention of 91.80% after 15000 cycles. The CMO||CMO-ASSC displayed a high energy density of 40.77 Wh kg−1 at a high-power density of 894.24 W kg−1 (based on the mass of active materials), which is the best value among ASSCs reported previously. Furthermore, the two CMO||CMO-ASSC coupled in series can charge up to 2.4 V and power two red color light-emitting-diodes (LEDs), demonstrating its practical applications as energy storage devices. Thus, this work paves a novel way to develop high-voltage ASSCs with large energy density and super long life energy storage devices.

A lossless compression and encryption mechanism for remote monitoring of ECG data using Huffman coding and CBC-AES

Biomedical signal processing provides a cross-disciplinary international forum through which research on signal and images measurement and analysis of clinical medicine and biological sciences are shared. The broadcast transmission in wireless body area networks raises serious security challenge when employed in biomedical applications. Electrocardiography (ECG) signal is frequently used for diagnosis of cardiovascular diseases. However, the ECG data need a large memory storage device due to continuous heart rate logs and vital parameter storage. Thus, compression schemes are applied to the ECG data before sending them to telemedicine centers for monitoring and analysis. Therefore, a proper compression mechanism cannot only improve the storage efficiency but also help in the rapid data transfer from one device to another due to its compact size. We propose a scheme using buffer blocks, peak detection, compression, and encryption mechanism to enable seamless and secure transmission of ECG signal from the sensor to the monitor. The study will prove that the quality of the reconstructed signals obtained using the proposed scheme, which uses discrete wavelet transform, Huffman coding, and Cipher Block Chaining-Advanced Encryption Standard algorithm approach, is superior to that obtained using unencrypted compression. Furthermore, the proposed system can provide quality-control compressed data, although the data have been encrypted. The experimental results show that the proposed system provides an effective means for assuring data security and compression performance for ECG data storage and transmission. The security of the scheme is applied against known attacks on privacy, such as eavesdropping and passive monitoring attack.

An Efficient Representation Using Harmony Search for Solving the Virtual Machine Consolidation

A data center with a large number of servers, large storage, and many network devices requires power for cooling to reduce heat generation, air conditioning, and emergency power generation facilities, in addition to power for operation internally consumed by infrastructure equipment. The power consumed by data centers worldwide makes up a large proportion. Although the size of data centers is expected to increase, we are already faced with power problems because stability is prioritized over efficiency when operating data centers in order to meet the Service Level Agreement (SLA) conditions. Most data centers are in a virtualization environment, and virtual machine consolidation using physical machine (PM) transitions to the idle mode through virtual machine (VM) migration has been suggested as one of the most effective ways to reduce the amount of power usage in a data center. This study takes into account the characteristics of virtualization environments and presents an algorithm that effectively solves VM consolidation (VMC) through operator design using a grouping representation method and a meta-heuristic method known as harmony search.

Big data storage configuration and performance evaluation utilizing NDAS storage systems

Recently, a large amount of multimedia data is rapidly increasing due to cloud activation. For this reason, there is a need for a technique capable of handling large amounts of data and large storage devices. In this way, a network storage device such as a NAS or a SAN is used to configure a large-capacity storage device in a network environment. In this paper, a large capacity storage device is constructed by using network direct connection storage device. We performed benchmark experiments to verify the scalability of the constructed storage devices using network direct attached storage.

5Wh Class Planar Sodium Nickel Chloride (Na-NiCl2) Battery Operated at below 200oc for Grid Scale Energy Storage

Sodium nickel chloride (Na/NiCl2) battery is one of the most promising candidates as a large scale electrochemical energy storage device. The battery comprises molten Na and NiCl2 as negative and positive electrodes, respectively, in its charged state, separating them by a β”-Al2O3 solid electrolyte (BASE). In order to facilitate fast sodium ion transport in the cathode compartment, molten NaAlCl4, as a secondary electrolyte (or catholyte), is infiltrated into the cathode materials powder. The battery typically operates at 250~300oC so as to maximize the ionic flux in the NaAlCl4 and through the solid electrolyte, and to minimize the dissolution of NiCl2into the melt. However, this efficient battery is yet to be widely used in grid scale energy storage applications since it is still expensive and hard to dramatically reduce the cell price mainly due to its use of expensive sealing technologies. The presentation introduces Korea-US collaborative efforts to develop a lower temperature operating sodium beta-alumina battery (LT-NBB) with a Na/NiCl2 chemistry. Since the novel battery runs at below 200oC, it can be fabricated at an ultra low manufacturing cost by introducing a new planar cell design with a greatly reduced number of cell components, and by eliminating expensive conventional sealing technologies. Enhanced degradation resistance of cathode materials is another important advantage of this technology. In this presentation, challenges and progress in building 5Wh class prototype LT-NBB cells using BASE with 70 mm in diameter will be discussed. Figure 1

Gravitational Level Effects on the Coupling Phenomena between Mass Transfer and Morphological Variation Rate

Gravitational Level Effects on the Coupling Phenomena between Mass Transfer and Morphological Variation Rate T. Nishida 1) , K. Nishikawa 1) , H. Matsushima 1) , T. Wakatsuki 1) , T. Homma2) , M. Rosso 3) and Y. Fukunaka4) 1) Dept. of Energy Sci. & Tech., Kyoto University 2) Dept. of Applied Chemistry, Waseda University 3) Ecole Polytecnique, Paris 4) Nanotechnology Research Center, Waseda University e-mail: hirofukunaka@gmail.com Development of advanced battery is the key for future space engineering field. Long life cycling must be maintained as well as the safety issue. Moreover, battery life must be predicted to reduce the number of space debri. Such technology achievements in space engineering field should be fed-back to the terrestrial applications including large scale energy storage devices. Generally speaking, battery reversibility is frequently governed by electrode surface flatness. Metal electrodeposition may generate irregular deposits with various morphologies. Coupling phenomena between the morphological or microstructural variations and ionic mass transfer rate must be fully understood to tailor the interface to create the unique physical properties as well as the ultra-high energy storage capacity. It is also indispensable for us to prolong the charging/discharging operation of secondary battery after longer term utilization under various environments. For liquid electrolyte, a precise study of these morphologies may be complicated by convective motion caused by gravitational force of buoyancy. Now the coupling phenomena are discussed in the case of Li in organic solvent PC or ionic liqid and Ag (or Cu) in AgNO3 (CuSO4) aqueous solution because they have been employed as negative electrode in space application as well as commercial use. The dendrite growth behavior of Li metal galvanostatically electrodeposited on Ni substrate in LiClO4-PC electrolyte was in-situ observed by a laser scanning confocal microscope. A Li dendrite precursor is stochastically evolved on Ni substrate probably through SEI. The initiation period of dendrite precursor becomes shorter with increasing current density and decresing LiClO4 concentration. Once it has been initiated, the ionic mass transfer rate starts to control the growth process of dendrite arm length, exceeding over the surface chemistry determining step. In order to excule the complexities due to SEI formation during the dendrite formation process, more simplified coupling behavior was studied in aqueous solution. 3M AgNO3aqueous solution was contained in a quasi-two dimensional electrolytic cell. Holographic interferometry technique was employed to monitor the ionic mass transfer rate. The thickness of electrolyte layer sandwiched by two slides glasses was measured to be 55 to 70 micrometer. The concentration profiles were formed around dendrite tips of silver electrodeposited at extremely high current densities. A uniform diffusion layer was formed along the cathode surface at the start of electrolysis. Electrochemical nucleation and growth phenomena on a substrate is expected under a considerably high overpotential. Following a certain incubation period, several dendrite tips began to protrude into the diffusion layer. The growth rates of these dendrites were related to concentration gradients around the tips, diffusivity, and transfer number of Ag+ ion. Giant-Macro step flow accompanied with dendritic growth of electrodeposited Ag in AgNO3 solution was dynamically observed in the image of Laser Confocal Scanning Microscope. These experiments must be engaged in microgravity facility which provides an ideal environment to built the physical model on electrolyte/electrode interfacial coupling phenomena without natural convection.

A Facile Bottom-Up Approach to Construct Hybrid Flexible Cathode Scaffold for High-Performance Lithium-Sulfur Batteries.

Lithium-sulfur batteries mostly suffer from the low utilization of sulfur, poor cycle life, and low rate performances. The prime factors that affect the performance are enormous volume change of the electrode, soluble intermediate product formation, poor electronic and ionic conductivity of S, and end discharge products (i.e., Li2S2 and Li2S). The attractive way to mitigate these challenges underlying in the fabrication of a sulfur nanocomposite electrode consisting of different nanoparticles with distinct properties of lithium storage capability, mechanical reinforcement, and ionic as well as electronic conductivity leading to a mechanically robust and mixed conductive (ionic and electronic conductive) sulfur electrode. Herein, we report a novel bottom-up approach to synthesize a unique freestanding, flexible cathode scaffold made of porous reduced graphene oxide, nanosized sulfur, and Mn3O4 nanoparticles, and all are three-dimensionally interconnected to each other by hybrid polyaniline/sodium alginate (PANI-SA) matrix to serve individual purposes. A capacity of 1098 mAh g-1 is achieved against lithium after 200 cycles at a current rate of 2 A g-1 with 97.6% of initial capacity at a same current rate, suggesting the extreme stability and cycling performance of such electrode. Interestingly, with the higher current density of 5 A g-1, the composite electrode exhibited an initial capacity of 1015 mA h g-1 and retained 71% of the original capacity after 500 cycles. The in situ Raman study confirms the polysulfide absorption capability of Mn3O4. This work provides a new strategy to design a mechanically robust, mixed conductive nanocomposite electrode for high-performance lithium-sulfur batteries and a strategy that can be used to develop flexible large power storage devices.