Large Storage Research Articles

Degradation Processes in Current Commercialized Li-Ion Batteries and Strategies to Mitigate Them

Lithium-ion batteries (LIBs) are now widely exploited for multiple applications, from portable electronics to electric vehicles and storage of renewable energy. Along with improving battery performance, current research efforts are focused on diminishing the levelized cost of energy storage (LCOS), which has become increasingly important in light of the development of LIBs for large transport vehicles and power grid energy storage applications. Since LCOS depends on the battery's lifetime, understanding the mechanisms responsible for battery degradation and developing strategies to increase the lifetime of LIBs is very important. In this review, the latest developments related to the performance and degradation of the most common LIBs on the market are reviewed. The numerous processes underlying LIB degradation are described in terms of three degradation loss modes: loss of lithium inventory (LLI), active positive electrode material loss and degradation, and active negative electrode material loss and degradation. A strong emphasis is placed on the most recent strategies and tactics for LIB degradation mitigation.

Genetic algorithm based optimization of nozzle profiles for a hydrogen turbo-expander

Liquid hydrogen plays an important role in the large scale storage and long-distance transportation. The development of hydrogen turbo-expander is the key to increase the efficiency of hydrogen liquefaction, reducing the cost of liquid hydrogen production, storage and transportation. In this paper, a numerical model of hydrogen nozzle is established and validated against experimental data. The performance of four traditional nozzle profiles in hydrogen turbo-expanders is simulated and analyzed. The poor uniformity of outlet flow angle is generally found in these nozzle profiles, leading to nozzle passage and impeller incidence losses in turbo-expanders. A genetic algorithm based method is proposed to optimize the nozzle profiles. The optimization objectives involve the nozzle efficiency, the uniformity of the nozzle outlet angle and the uniformity of the outlet Mach number. The deviations in the outlet angle and Mach number of the optimized nozzle are reduced by 50.26 % and 14.03 %, respectively, while the nozzle efficiency reaches 98.64 %. The matching characteristics of the optimized nozzle with the impeller are obtained via simulation of a hydrogen turbo-expander, and the results indicate the expansion efficiency can be increased by 1.53 %.

All-solid-state flexible micro-supercapacitors with enhanced electrochemical performance obtained by hybridizing mxene with butterfly graphite

Abstract All-solid-state flexible micro-supercapacitors (MSCs) have the advantages of large energy storage capacity, small size, and good flexibility, which can be used as micro power sources. A 2D titanium carbide (MXene) has metallic conductivity, good hydrophility, and excellent processing properties, showing its great potential in flexible MSCs. However, the self-packing of MXene sheets hinders charge transfer and ion transport, limiting its electrochemical capacity. Herein, MSCs were prepared from a composite material of butterfly-like graphite (BTG) and MXene. BTG was inserted into the MXene layer to prevent its overs tacking, which promotes the diffusion of electrolytes and improves the electrochemical capacity of MSCs. As a result, MXene/BTG MSCs exhibit a large capacitance of 177.9 mF cm−2 at 5 mV s−1. In addition, the specific capacitance retention of MXene/BTG-30% MSCs can reach 80.4% in 0.1 -1 mA cm−2.

Multi-source wavefield reconstruction of distributed acoustic sensing data using compressive sensing and seismic interferometry.

Seismic data recorded by distributed acoustic sensing (DAS) interrogator units on deployed optical fiber are being used for a variety of subsurface imaging and monitoring investigations. To reduce the costs of active-source DAS surveying applications, seismic interferometry can be applied to estimate inter-sensor wavefields from DAS records. However, recording long-term records for ambient interferometry requires considerable data storage and sections of DAS optical fibers may be unusable because of broadside sensitivity considerations from the DAS fiber orientation and due to localized coherent energy sources with amplitudes significantly larger than the ambient signal of interest. Compressive sensing, a wavefield reconstruction technique, can mitigate the problems of large data storage and unusable data. We apply compressive sensing-based multi-source wavefield reconstruction to estimate correlograms of ambient DAS records from a fiber array in Perth, Australia. The multi-source method uses all available virtual-source gathers for simultaneous wavefield reconstruction and is different from the conventional single-source method that separately reconstructs individual virtual-source gathers. Using the Fourier and curvelet transforms to sparsify interferometric wavefields, we show that multi-source reconstruction is applicable to the DAS data and that the Fourier multi-source reconstruction can improve the recovered wavefields by approximately 5-10 dB, compared to the Fourier and curvelet single-source wavefield reconstructions.

Performance Analysis of an E-commerce Website Using Distributed Servers (Case Study: Ecommerce Bumdes Sarining Kukuh Winangun)

Digital transformation has significantly altered our interactions by leveraging the internet for fast global information exchange and collaboration. This shift impacts businesses, individuals, organizations, and governments by increasing the demand for fast, reliable web services. To meet these demands, many organizations are turning to distributed server infrastructures, which help handle large storage needs and avoid performance issues. This research focuses on creating a distributed web server system that uses Round-Robin load balancing to evenly distribute traffic and enhance performance. The Round-Robin algorithm’s simplicity and effectiveness in balancing loads, combined with the advantages of virtualization, such as cost efficiency, improved performance, and better resource management are central to this approach. Virtualization also offers improved scalability, accuracy, and security, further enhancing overall system efficiency and effectiveness in data centers. This research evaluates and contrasts the performance of websites utilizing distributed servers against those using single servers. The findings indicate that websites with distributed servers significantly outperform those with single servers. Specifically, distributed servers offer response times that are 5.8 times faster, achieve 2.2 times more successful responses, and transfer 2.1 times more data than single servers. Additionally, single servers experience a much higher rate of timeouts, with 14.2 times more occurrences compared to distributed servers.

Weighted Attribute-Based Proxy Re-Encryption Scheme with Distributed Multi-Authority Attributes.

Existing attribute-based proxy re-encryption schemes suffer from issues like complex access policies, large ciphertext storage space consumption, and an excessive authority of the authorization center, leading to weak security and controllability of data sharing in cloud storage. This study proposes a Weighted Attribute Authority Multi-Authority Proxy Re-Encryption (WAMA-PRE) scheme that introduces attribute weights to elevate the expression of access policies from binary to multi-valued, simplifying policies and reducing ciphertext storage space. Simultaneously, the multiple attribute authorities and the authorization center construct a joint key, reducing reliance on a single authorization center. The proposed distributed attribute authority network enhances the anti-attack capability of cloud storage. Experimental results show that introducing attribute weights can reduce ciphertext storage space by 50%, proxy re-encryption saves 63% time compared to repeated encryption, and the joint key construction time is only 1% of the benchmark scheme. Security analysis proves that WAMA-PRE achieves CPA security under the decisional q-parallel BDHE assumption in the random oracle model. This study provides an effective solution for secure data sharing in cloud storage.

A strategy of forming sandwich electrodes based on graphene and two-dimensional transition metal dichalcogenides as supercapacitors to avoid gas evolution

Two-dimensional (2D) materials such as transition metal dichalcogenides (TMDC) are well-recognized as excellent electrode materials for energy storage applications due to the ion intercalation characteristic. However, gas evolution is central to the problems that limit the potential window of these materials in the energy storage context. This is because the TMDC can behave as an electrocatalyst, especially in an acid environment. Herein, a novel design of electrode materials for avoiding gas evolution in supercapacitor devices was formed using the sandwich configuration between graphene (GP) and TMDC. A family of transition metal dichalcogenide (TMDC) materials e.g., molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), tungsten disulfide (WS2), and tungsten diselenide (WSe2) including GP was constructed as a layer-by-layer electrode materials, like a “sandwich”. In this work, we provide a straightforward method for creating GP/TMDCs/GP free-standing electrodes that have the necessary properties, such as large surface area and high conductivity for electrolyte diffusion. The GP sandwich on both sides of the electrode can diminish the gas evolution of TMDCs in acidic conditions. This makes the sandwiched electrodes perform a wider electrochemical window up to 1.0 V, in 1.0 M H2SO4. Note that the gas evolution e.g. hydrogen typically occurs at about −0.35 V (onset). Compared with conventional GP/activated carbon, the specific capacitances of “sandwich” GP/MoS2/GP, GP/MoSe2/GP, GP/WS2/GP, and GP/WSe2/GP devices are improved by 7.4, 6.2, 14.8, and 17.3 %, respectively. The findings also indicate that the developed sandwich electrode may be a suitable choice for the creation of future large energy storage systems with a high intercalation capacitance in layered materials.

Electrochemical Behaviors and Doping Rules of NaRhO2 Cathode Materials for Sodium-Ion Batteries.

Sodium-ion batteries (SIBs) have great advantages for energy storage and conversion due to their low cost and large storage capacity. Currently, NaRhO2 is used as an electrode material for sodium-ion batteries. Doping first- and second-row transition metals has been carried out to comprehensively assess NaRhO2 as a cathode material. The geometric and electronic structures and electrochemical and doping behaviors of NaRhO2 cathode materials for SIBs have been investigated using density functional theory calculations. The results show that the bond lengths of Rh-O in NaRhO2 decrease during sodium deintercalation. The band gap of NaRhO2 with sodium extraction gradually reduces. The density of states of NaxRhO2 shows that the interaction between the Rh-4d and O-2p orbitals increases and the orbitals shift toward the right. The average intercalation voltage of NaxRhO2 cathode material increased from 2.7 to 3.9 eV. After doping with first- and second-row transition metal elements from Sc to Zn and Y to Cd, the changes in the band gaps of the doped NaRhO2 materials exhibit a W-type rule. In contrast, their magnetic moments show a reverse W-type rule. These findings on the pristine and doped NaRhO2 can provide theoretical guidance for the preparation of novel electrode materials suitable for sodium-ion batteries.

Carbon-based phase change composites with directional high thermal conductivity for interface thermal management

Phase change materials (PCMs) can provide a buffer platform for thermal management systems to deal with thermal runaway problems. However, prompt heat dissipation and cost-effective thermal regulation in desired devices are still limited by insufficient thermal transport behavior and liquid leakage of PCMs. Here, we report a facile strategy to develop high-power-density device by carbon-based phase change composites (PCCs) with directional high thermal conductivity. The synergistic effect of self-assembled aligned graphite nanoplatelets (GNPs) inside the resultant PCCs on thermal transport and structural reinforcement enable the PCCs to show high thermal conductivity (in-plane KPCCs of up to 32.86 W m−1 K−1), large heat storage density (158.2–248.3 J g−1), thermal cycling stability, and leakage-proof properties. Furthermore, a PCC-based high-power-density energy device is demonstrated for the tunable thermal regulation by coordinating the orientation of GNPs heat conduction skeleton inside the PCCs with the thermal transport direction of device. The PCC-based module maintains a suitable temperature range of 149–151 °C under various operating conditions and exhibits a decrease of ∼10 °C in the surface peak temperature of power device, showing excellent temperature control performance. Our work holds promising application prospects in the engineering scalable functional PCCs for thermal regulation of electronics and interface thermal management.

Enhanced multiferroic properties of NZCFO-BNFSO composites: Synthesis, characterization, and performance analysis

The structural and multiferroic properties of xNi0.24Zn0.58Cu0.18Fe2O4(NZCFO)-(1-x)Bi0.9Nd0.1Fe0.95 Sc0.05O3(BNFSO) are explored in this paper. Bi2O3 additives significantly lower the sintering temperature of the composites. The XRD analysis validates the coexistence of hexagonal perovskite BNFSO and spinel NZCFO phases. The FESEM images illustrate an almost homogeneous amalgamation of the BNFSO and NZCFO grains. The real part of initial permeability and the relative quality factor increases with NZCFO contents in the composites. The maximum permeability is observed for the composite with 80 % ferrite content. The ferroelectric BNFSO exhibits antiferromagnetic behavior and with the increase in NZCFO the saturation magnetization increases significantly. The dielectric constant confirms typical dielectric dispersion at low frequencies because of Maxwell–Wagner space charge polarization. The P-E hysteresis measurement reveals that the composite with 40 % ferrite content exhibits the highest loop area and hence a large energy storage capacity. Incorporating BNFSO and NZCFO into the composite boosts the multiferroic properties, which might be a suitable alternative to single-phase multiferroics.

Design and analysis of rigid-elastic coupling origami flashers with bistable characteristics

Origami flashers are frequently used in the design of deployable structures due to their large storage ratio and simple structure. However, origami flashers are not foldable without the flexible deformation of the structural components. On the other hand, conventional origami flashers could not be maintained in the deployed configuration with enough supporting stiffness because of the flexibility of the facets and creases, which limits their practical applications. By analyzing the mobility of the rigid origami flashers, we find that the origami flashers have a bistability-like property. Based on this, we propose a method to design rigid-elastic coupling origami flashers with bistable characteristics. The rigid-elastic coupling origami flashers consist of rigid facets, zero-stiffness creases, and elastic ropes. The bistable folding characteristics are analyzed by theoretical models, and demonstrated by numerical methods and experiments. Such bistable characteristics allow for the deployment of the origami with less energy consumption, while achieving greater supporting stiffness in the deployed configuration. The effect of different parameters on the dynamic performance is also investigated. A fabrication method of the novel system is proposed and verified by a physical prototype. The rigid-elastic coupling origami flashers facilitate their potential applications in space engineering.

Design of an innovative flow isolation device (FID) as an air flow barrier to control the temperature of large storage areas in cold room applications

The virus transmission chain of Covid-19 has a resulted in a significant, global impact on social and working life. Covid-19 vaccines require protective refrigerated conditions during delivery and storage. Warehousing and transportation of these vaccines need to be properly controlled to maintain the product quality and efficacy. Logistics companies developed large-scale refrigerated warehouses as storage relay stations. The heat convection between two rooms of the large-scale, low-temperature warehouses with different temperatures for example (5 °C, -15 °C) should be prevented to improve efficiency. In this study, an innovative flow isolation device (FID) was designed in Taipei Tech to block the storage areas, preventing heat convection. This device can maintain a constant low-temperature in warehouses used for vaccine storage. The axial flow fan draws air from the protected zones (5 °C, -15 °C) into the device. A perforated plate stabilizes the flow rate and maintains a uniform flow direction, creating a flow barrier created between two rooms. This flow can significantly block the heat convection induced by two warehouses with different temperatures. The computational fluid dynamics (CFD) software Ansys Fluent is used to simulate the effect of the FID on the prevention of the heat convection between two rooms. Different case studies were simulated at different machine sizes and supply air flow speeds. The simulated flow patterns and velocity fields are used to evaluate the highest isolation efficiency. The findings show that the FID device can effectively maintain the low temperature of the warehouse. Moreover, the FID helps to avoid heat loss and maintain thermal comfort in working areas, reducing the risk of hypothermia.

Assessment of Technoeconomic Opportunities in Automation for Nuclear Microreactors

Achieving full decarbonization of all economic sectors remains a challenge, especially in niche markets. For example, remote communities and industrial or mining activities detached from the main electric grid heavily rely on fossil fuels, similar to urban and industrial microgrids with combined heat and power needs. A combination of renewables and energy storage is often not suitable due to cost, reliability, intermittency, and large storage requirements. Small nuclear reactors with a flexible purpose could serve these applications. Microreactors (MR) are a class of reactors that are compact, factory manufactured, transportable, and self-regulating. Typically, they generate much less power than their large reactor counterparts. The main advantages of microreactors include the versatile nature of the energy produced, the reliability of supply, and freedom from having to transport and store large quantities of fuels on-site, coupled with the absence of dependence on an electrical grid. A strong business case is needed to move from the microreactor prototype to the commercialization phase. In fact, fossil fuels are still relatively inexpensive, and in the near term, carbon credits will be available to virtually compensate for emissions. For microreactors, one of the main costs in operation and maintenance (O&M) is their staffing levels. In this study, we investigate how to optimize the number (and thus the cost) of workers, moving from a traditional, fully manned, on-site personnel approach to an unmanned, remote personnel approach. We examine four different staffing models that can be implemented as the technology matures and evolves. We estimate the staffing needs of each model and build a business case to justify the substitution of on-site personnel with adequate technologies. To do so, we propose a cost model to quantify potential cost reductions from automating O&M activities. The model accounts for both the reduction in cost derived from the reduced number of full-time-equivalent (FTE) employees and the increase in cost derived from the need to buy new control hardware as needed. Applying the cost model that we created to different scenarios, an on-site O&M cost reduction exceeding 80% can be expected. Additionally, we found that it is more impactful to focus on automating routine O&M tasks rather than attempting to automate transient management (shutdowns, restarts, monitoring condition deviations). In fact, transients typically account for less than 1% of the total FTE time spent on the reactors.

Integration of a Hydrogen Storage Cavern into the Carbon2Chem® Project

AbstractUnderground salt caverns allow large hydrogen storage capacities at low specific costs. Such storage is required to balance fluctuating hydrogen supply and constant demand of large consumers as a methanol plant from the Carbon2Chem® project. The geological and technical feasibility for developing up to 168 Mio. m3 (n.c.) or 595 GWh of working gas capacity until 2040 at a location in the Lower Rhine Bay is described. Various options for realization as well as a novel process for cavern leaching parallel to hydrogen storage operation are evaluated. Further work is required including geological exploration and optimization of brine production. The main hurdles for investment decisions are the political uncertainties on the hydrogen storage market design and on the ramp‐up of the hydrogen market.

Techno-economic assessment of supercritical, cold liquid, and dissolved CO2 injection into sub-seafloor basalt

Injecting CO2 into subsea basalt can provide permanent storage via multiple trapping mechanisms, including mineralization reactions which convert the CO2 into solid carbonates over time. Injecting CO2 together with water can accelerate the process of mineralization, but presents additional challenges, such as high energy and water requirements. A techno-economic model of CO2 transport and injection into ocean basalt was developed to compare injection strategies using pure supercritical CO2, pure liquid CO2, and CO2 dissolved in seawater. The model was applied to a representative injection site off the coast of British Columbia, Canada. Injection of CO2 dissolved into seawater was found to be more energy and cost intensive than injection of supercritical or liquid CO2; this is primarily due to the reduced quantities of CO2 that can be injected into each well, and additional pumping energy required for the accompanying seawater. For the base assumptions, transport and storage costs for supercritical, liquid, and dissolved injection were estimated as $43/t, $38/t, and $250/t respectively. Their energy requirements were estimated as 93 kWh/t, 90 kWh/t, and 213 kWh/t respectively. The current best estimates of geological parameters for ocean basalt suggest good injectivity and very large storage capacities per well. This may help to compensate for the additional project expenses incurred by deep water, allowing cost-effective liquid and supercritical injection. However, this result is sensitive to high uncertainties in both geological parameters and component cost data.

Achieving a Rapid Na+ Migration and Highly Reversible Phase Transition of NASICON for Sodium-Ion Batteries with Suppressed Voltage Hysteresis and Ultralong Lifespan.

Sodium ion batteries have attracted great attention for large scale energy storage devices to replace lithium-ion batteries. As a promising polyanionic cathode material of sodium-ion batteries, Na3V2(PO4)2F3 (NVPF) belonging to NASICON exhibits large gap space and excellent structural stability, leading to a high energy density and ultralong cycle lifespan. To improve its stability and Na ion mobility, K+ cations are introduced into NVPF crystal as in situ partial substitution for Na+. The influence of K+ in situ substitution on crystal structure, electronic properties, kinetic properties, and electrochemical performance of NVPF are investigated. Through ex situ examination, it turns out that K+ occupied Na1 ion, in which the K+ does not participate in the charge-discharge process and plays a pillar role in improving the mobility of Na+. Moreover, the doping of K+ cation can reduce the bandgap energy and improve the electronic conductivity. Besides, the optimal K+ doping concentration in N0.92K0.08VPF/C is found so as to achieve rapid Na+ migration and reversible phase transition. The specific capacity of N0.92K0.08VPF/C is as high as 128.8 mAh g-1 at 0.2 C, and at 10 C its rate performance is excellent, which shows a capacity of 113.3 mAh g-1.

Research on the application and prospect of RFID technology

As Radio Frequency Identification (RFID) has the advantages of fast scanning speed, small size, large data storage, high security, and other technologies, it is widely used in various fields to upgrade working efficiency. Meanwhile, as one of the research topics of the Internet of Things (IoT), Radio Frequency Identification also provides the possibility for the development and application scope of IoT. Based on the application principle of Radio Frequency Identification technology, this paper discusses the application of Radio Frequency Identification in the two fields of intelligent libraries and intelligent logistics through literature review and theoretical analysis. Through the analysis of the current situation of RFID application in the library management and logistics industry, this paper discusses the advantages and shortcomings of radio frequency identification technology, and according to the existing problems the future direction of development of the corresponding improvement proposals to promote the further improvement of the application of radio frequency identification technology.

Tailoring Alkalized and Oxidized V2CTx as Anode Materials for High-Performance Lithium Ion Batteries.

V2CTx MXenes have gained considerable attention in lithium ion batteries (LIBs) owing to their special two-dimensional (2D) construction with large lithium storage capability. However, engineering high-capacity V2CTx MXenes is still a great challenge due to the limited interlayer space and poor surface terminations. In view of this, alkalized and oxidized V2CTx MXenes (OA-V2C) are envisaged. SEM characterization confirms the accordion-like layered morphology of OA-V2C. The XPS technique illustrates that undergoing alkalized and oxidized treatment, V2CTX MXene replaces -F and -OH with -O groups, which are more conducive to pseudocapacitive properties as well as Na ion diffusion, providing more active sites for ion storage in OA-V2C. Accordingly, the electrochemical performance of OA-V2C as anode materials for LIBs is evaluated in this work, showing excellent performance with high reversible capacity (601 mAh g-1 at 0.2 A g-1 over 500 cycles), competitive rate performance (222.2 mAh g-1 and 152.8 mAh g-1 at 2 A g-1 and 5 A g-1), as well as durable long-term cycling property (252 mAh g-1 at 5 A g-1 undergoing 5000 cycles). It is noted that the intercalation of Na+ ions and oxidation co-modification greatly reduces F surface termination and concurrently increases interlayer spacing in OA-V2C, significantly expediting ion/electron transportation and providing an efficient way to maximize the performance of MXenes in LIBs. This innovative refinement methodology paves the way for building high-performance V2CTx MXenes anode materials in LIBs.

Study on Rapid Simulation of the Pre-Cooling Process of a Large LNG Storage Tank with the Consideration of Digital Twin Requirements

The pre-cooling of a large LNG storage tank involves complex phenomena such as heat transfer, low-temperature flow, gas displacement, and vaporization. The whole pre-cooling process could take up to 50 h. For large-scale, full-capacity storage tanks, it is particularly important to accurately control the pre-cooling temperature. Digital twin technology can characterize and predict the full life cycle parameters from the beginning of pre-cooling development to the end and even the appearance of damage in real time. The construction of a digital twin platform requires a large number of data samples in order to predict the operating state of the device. Therefore, a simulation method with high computational efficiency for the pre-cooling process of LNG tanks is of great importance. In this paper, the mixture model and discrete phase model (DPM) are applied to simulate the pre-cooling process of a large LNG full-capacity tank. Following Euler–Lagrange, the DPM greatly simplifies the solution process. Compared with the experimental results, the maximum error of the DPM simulation results is less than 11%. Such a highly efficient simulation method for the large LNG full-capacity storage tank can make it possible to build the digital twin platform that needs hundreds of data model samples.

An In-Memory-Computing Structure with Quantum-Dot Transistor Toward Neural Network Applications: From Analog Circuits to Memory Arrays

The rapid advancements in artificial intelligence (AI) have demonstrated great success in various applications, such as cloud computing, deep learning, and neural networks, among others. However, the majority of these applications rely on fast computation and large storage, which poses significant challenges to the hardware platform. Thus, there is a growing interest in exploring new computation architectures to address these challenges. Compute-in-memory (CIM) has emerged as a promising solution to overcome the challenges posed by traditional computer architecture in terms of data transfer frequency and energy consumption. Non-volatile memory, such as Quantum-dot transistors, has been widely used in CIM to provide high-speed processing, low power consumption, and large storage capacity. Matrix-vector multiplication (MVM) or dot product operation is a primary computational kernel in neural networks. CIM offers an effective way to optimize the performance of the dot product operation by performing it through an intertwining of processing and memory elements. In this paper, we present a novel design and analysis of a Quantum-dot transistor (QDT) based CIM that offers efficient MVM or dot product operation by performing computations inside the memory array itself. Our proposed approach offers energy-efficient and high-speed data processing capabilities that are critical for implementing AI applications on resource-limited platforms such as portable devices.