Design Of Energy Storage System Research Articles

High-performance asymmetric pseudocapacitor based on NiCo2O4@MnO2 cathode and N-doped graphene anode

The design and fabrication of scalable energy storage systems are crucial for portable applications, demanding advanced materials through large-scale and facile processing. In this report, an asymmetric solid-state pseudocapacitor (ASPC) is assembled using a core–shell NiCo2O4@MnO2 composite and solution-processed nitrogen-doped graphene (N-GP) as the positive and negative electrodes, respectively. With interconnected porous structures, the electrodes based on N-GP and NiCo2O4@MnO2 offer high specific capacitance and rate capability, broad operation voltage, and a binder-free design with no added conductive agent. With these benefits, the ASPC with a PVA-KOH electrolyte exhibits a specific capacitance of 103.3F g−1 at 1 A/g and exceptional energy density of 36.73 Wh kg−1 at a power density of 792 W kg−1. In addition, the specific capacitance retention reaches 90.9 % after 5000 cycles, indicating excellent cycling stability. In the broader context of solid-state supercapacitors based on solution-processed graphene, this ASPC exhibits highly competitive performance, establishing it as a promising candidate for advanced energy storage.

A self-adaptive joint optimization framework for marine hybrid energy storage system design considering load fluctuation characteristics

Recently, with the development of new energy technologies, all-electric ships (AESs) with hybrid energy storage system (HESS) are becoming a promising solution to reduce fuel consumption and emissions. However, the high maneuverability of ships during the actual navigation places higher performance requirements on the HESS, which presents a nonlinear and multi-objective challenge for the HESS design. Therefore, it is necessary to consider the coupling between HESS sizing and energy management strategy (EMS). In this paper, a self-adaptive joint optimization framework (SJOF) for marine HESS design considering load fluctuation characteristics is proposed, which can find the optimal decision solution with excellent system economic and battery life performance for AES HESS design. Based on the rain flow counting (RFC) method, a multi-objective joint optimization method considering life cycle cost (LCC) and battery degradation index (BDI) is introduced into SJOF. Besides, a novel EMS including the self-adaptive segmentation mechanism (SSM) and power allocation is proposed, which can achieve the most efficient energy scheduling.

A methodical approach for the design of thermal energy storage systems in buildings: An eight‐step methodology

AbstractRecent research focuses on optimal design of thermal energy storage (TES) systems for various plants and processes, using advanced optimization techniques. There is a wide range of TES technologies for diverse thermal applications, each with unique technical and economic characteristics. Matching an application with the most suitable TES system remains challenging. This study proposes an eight‐step design methodology guiding the process from describing the thermal process to defining the most appropriate TES based on constraints and requirements. The steps include specifying the thermal process, system design parameters, storage characteristics, integration parameters, key performance indicators, optimization method, tools, and design robustness. Seven already‐designed TES systems are evaluated to assess the methodology's effectiveness, where the design procedures have been adapted to the proposed steps. Case studies involve various applications with both sensible and latent TES systems, demonstrating the applicability of the proposed design procedure. A significant diversity exists among the design cases regarding the design objective, input, design, and output parameters. Nevertheless, the design procedure in each case can be deconstructed into the outlined design steps. The last design step has been excluded from all case studies due to insufficient information regarding the robustness of the design process. The paper demonstrates how a methodical approach can be applied to examine the TES design and the integration. The design steps proposed in this study can serve as a foundation for developing a more systematic approach for designing TES systems in future works, resulting in simplifying the design process.

Urban Rail System Modeling and Simulation Based on Dynamic Train Density

To further improve the simulation calculation ability of urban rail traction systems during the peak operation period and provide an accurate and reliable simulation tool for the subsequent train schedule and energy storage system design, a multi-train circuit model with a bilateral power supply was established in this paper, and a power calculation algorithm based on dynamic train density was designed. The circuit topology in the model can be dynamically adjusted according to the number of trains to improve the operation rate. Based on the spatial and electrical data of a real section of the subway, the urban rail circuit model was built on the MATLAB platform, and the actual operation data of the subway was imported for verification. The experimental results show that the multi-train model can accurately reflect the influence of voltage fluctuations on the traction system under different train running conditions, and the results fit the actual operation conditions. By comparing the influence of different train intervals on the RBE (regenerative braking energy) utilization, the results show that the optimal RBE utilization rate can be achieved by adjusting the train interval in the peak period.

Optimal energy storage system design for addressing uncertainty issues in integration of supply and demand-side management approaches

The primary goal of Sustainable Development Goal 7 (SDG 7) is to increase renewable energy use to reduce reliance on fossil fuels and mitigate climate change. Energy-intensive industries can benefit from in-house renewable power generation, reducing their reliance on fossil fuel-based grid power and making processes greener. However, integration among power generation/purchase, energy storage systems (ESS), and power consumption is crucial to overcome the intermittent nature of renewable power sources. ESS plays a vital role in increasing resilience and optimizing material production based on power availability and pricing. The efficacy of ESS needs critical evaluation considering cost, efficiency, and uncertainties related to renewable power generation and material product demand. The paper proposes two scenario-based optimization approaches to assess the impact of uncertainties on the integrated supply and demand side management (ISDM) system, focusing on lithium-ion batteries and cryogenic energy storage (CES). Compared to the conservative approach of the scenario-based robust optimization (SRO) method, the proposed stochastic simulation optimization (SSO) method provides a ‘risk-neutral’ solution, which is 6.45% less than the minimum expected cost solution. The analysis also suggests that lithium-ion batteries are more economically effective for the proposed integrated framework than CES, resulting in almost a 29% reduction in operating costs compared to no battery option. The proposed framework could contribute to sustainable and economically viable energy management practices in energy-intensive industries. Further research and implementation of such frameworks could accelerate the adoption of renewable energy and energy storage technologies in industrial processes.

High energy density biomass-derived activated carbon materials for sustainable energy storage

Biomass-derived activated carbons are promising materials for sustainable energy storage systems such as aqueous supercapacitors and Zn-ion capacitors due to their abundance, low cost, tunable porosity, and heteroatom-rich structures. Herein, we report biomass derived carbon materials fabrication via a two-step activation method. The activated carbons possess well-tuned pore structures and high heteroatom content, resulting in remarkable surface area, ultrahigh micropore volume, and good wettability. The symmetrical supercapacitors and aqueous Zn-ion capacitors were assembled using the produced activated carbons. The 2PA-6-800 supercapacitor delivers an ultrahigh rate capability (up to 10,000 mV s−1) and promising cycle life, retaining 66.3 % of its initial performance after 33,000 galvanostatic charge–discharge cycles. The assembled 2PA-6-800-based ZIC delivers a superior specific capacitance of 785.0 F g−1, a maximum energy density of 352.5 Wh kg−1, and a remarkable power density of 60.3 kW kg−1. The outstanding performance is attributed to the two-step activation method, high heteroatom content, and the structural integrity of the biomass derived AC to the ZIC device architecture. This work contributes to the design and development of high-performance, safe, and sustainable energy storage systems.

Thermodynamic design of the novel energy storage system based on liquid carbon dioxide for a 17 MW concentrated solar thermal power plant

Currently, the majority of electric power generation in Iran is provided through fossil fuel power plants. Recently, the effort to increase the share of renewable energy in the energy supply portfolio is increasing. Naturally, none of the renewable energy plants in this country are currently equipped with an energy storage system. The first concentrated solar thermal power plant of this country is currently under construction with a nominal capacity of 17 MW, but it has not yet been put into operation. Therefore, in this research, the thermodynamic design of the energy storage system based on liquid carbon dioxide is presented to be coupled with it. The results of the research showed that the energy generated per unit of storage volume of the designed system is equal to 17.6 kWh and the thermal, exergy and round-trip efficiencies of the system are equal to 36.14 %, 61.51 % and 40.63 %, respectively. Also, the effect of turbine and pump efficiencies on the output of the designed energy storage system was investigated and it was shown that with the increase in turbine efficiency, the effectiveness of the system enhances; while increasing the pump efficiency does not have much effect on the performance of the system.

Design and performance evaluation of thermal energy storage system with hybrid heat sources integrated within a coal-fired power plant

The operational flexibility of coal-fired power plants (CFPPs) should be effectively enhanced to accommodate large-scale photovoltaic and wind power within the power grid. The integration of thermal energy storage (TES) systems is a potential way to enlarge the load-cycling range of CFPPs. To achieve high operational flexibility of CFPPs and high round-trip efficiency of TES systems, TES systems with hybrid heat sources including the heat converted from power by power-to-heat (P2H) devices and transferred from the reheat steam integrated into CFPP were proposed. Then, simulation and thermo-economic analysis models were developed, and the system design procedure was provided. Results show the minimum power load ratio is decreased from 30 % to about 16 % by storing heat from the reheat steam within the TES system, and then to zero by converting electricity to heat with P2H devices. The mode P-basic constitutes two double-tank molten salt TES systems, which are charged by the heat converted from power by P2H devices and the heat transferred from the reheat steam, respectively. It is discharged by releasing the heat to water/steam cycle of CFPP, and the highest equivalent round-trip efficiency of mode P-basic is up to 62.97 %. Moreover, mode P-basic exhibits the largest total cost of the equipment and storage materials at $58.26 million while it has the largest net present value at $103.79 million and the corresponding payback period is 5 years.

Design and Simulation of Supercapacitor Energy Storage System

STATCOMs are widely used to enhance power system stability. They can exchange reactive power with the power system, but they have limited ability to exchange real power because they don’t include energy storage devices. STATCOMs coupled with energy storage devices such as batteries have been introduced to improve their ability to exchange real power. However, batteries have a limitation in their maximum deliverable power because of the slow chemical process required to release their energy. The trend now is to use supercapacitor energy storage systems "SCESS" as energy storage for STATCOMS. Supercapacitors have lower energy storage but higher power exchanging capability compared to batteries. This paper presents the analysis, design, and control of a supercapacitor energy storage system (SCESS) for a STATCOM. A peak current mode controller is used to control the SCESS system. Simulation results of the SCESS system are presented which indicate excellent performance of the proposed SCESS system.

Investigation of water adsorption characteristics of MgCl2 salt hydrates for thermal energy storage: Roles of hydrogen bond networks and hydration degrees

Thermochemical energy storage holds great promise in solar energy applications, and MgCl2 hydrate salt is considered a promising material for medium and low-temperature thermochemical energy storage. Understanding the adsorption behavior of water molecules in MgCl2 hydrate salts and uncovering the underlying mechanisms are crucial for designing efficient thermochemical energy storage systems. This paper investigated the water adsorption characteristics of MgCl2 hydrate salt utilizing the Grand Canonical Monte Carlo (GCMC) method and captured the adsorption isotherm and concentration distributions of water molecules in MgCl2 hydrate salts pores at various temperatures. The results demonstrate that at low temperatures, particularly when the pore size is small (D < 0.8 nm), the interconnected hydrogen bond network plays a crucial role in enhancing the water adsorption capacity of pure MgCl2. As the temperature increases, the influence of hydrogen bond networks diminishes, and their impact on the water adsorption capacity becomes negligible. Moreover, the hydration degrees of MgCl2 salt significantly influence their water adsorption capacity. MgCl2·6H2O exhibits the best water-uptake performance, followed by MgCl2·4H2O, while MgCl2·2H2O displays the worst water-uptake performance. These findings shed light on the adsorption behavior of water molecules in MgCl2 hydrate salt and offer valuable insights into the design and optimization of efficient thermochemical energy storage systems. Such knowledge is essential for advancing the utilization of thermochemical energy storage in solar energy applications.

Exploring MBSE for asset digitalisation in the energy sector. A Battery Energy Storage System design study

This study explores an approach to improve the design process for complex systems in the energy industry, with a focus on how digitalisation-enhanced procedures and Model-Based System Engineering (MBSE) methodologies are assisting in their goals. The main purpose is to analyse how MBSE tools can be used for enhancing design and development. processes with special emphasis on Battery Energy Storage Systems (BESS). The use of digital technologies in the design process of complex systems expands the possibilities and ambitions of technological solutions. A complex system seeks to solve problems that address multiple areas of knowledge. For its design, collaboration in multidisciplinary teams is essential. The increase in the scope of projects makes it essential to formalize the integration of partial solutions in a System of Systems (SoS) that solves the general problem consistently and cohesively. In a more detailed case study, the present research applies System Composer from Mathworks for supporting requirements management, traceability, and system architecture design. Among the main findings of this contribution, it describes the use of MBSE and how it might integrate with digitalisation as well as servitization. Summarizing, this research states that the advantages of MBSE are the increase of efficiency in the internal processes, providing additional value in services to customers. In fact, there is a need for more research about the relationship of MBSE, digitalisation, and servitization.

Experimental research on the effect of graphite on heat transfer performance of a latent heat storage system

Phase change materials (PCMs) provide a good resolution for the latent heat storage system which can be used in many application fields such as solar energy utilization and waste heat recovery. This study aims to experimentally investigate the impact of graphite powder on the thermal characteristics and heat transfer performance of paraffin with ceresin (PC) as a PCM, using water as the heat transfer fluid. Experimental tests were conducted to analyze the heat transfer performance of PC and the influence of graphite powder on its thermal characteristics. Different masses of graphite powder were employed to assess their effects on the heating rate and the time required for PC to reach its melting temperature. The experimental results revealed that the addition of graphite powder improved the heating rate of both PC and water, attributed to its high thermal conductivity. Furthermore, the time for PC to reach the melting temperature was decreased with varying amounts of graphite powder, achieving a maximum reduction of 17.2% with the addition of 40 g of graphite powder. However, the effectiveness of graphite powder in enhancing heat transfer efficiency was found to be limited, with the optimal promotion effect observed at around 40 g of graphite powder for 500 g of PC. The findings of this investigation provide valuable insights for the design of phase change energy storage systems, with potential applications including heat pump drying units, greenhouse energy storage in modern agriculture, and solar energy storage utilization technology. The theoretical basis established can contribute to the development and optimization of PCM-based systems in diverse practical scenarios.

Sizing method of a novel hybrid energy storage considering adaptive inertia control

This paper introduces a novel hybrid energy storage system (HESS) with a focus on adaptive inertia control and its sizing methodology. The HESS is built upon the modular multilevel converter (MMC) topology, incorporating hybrid submodules, batteries, and supercapacitors (SC). The sizing method for the hybrid energy storage system in the proposed HESS is discussed, with a specific emphasis on its application in frequency response scenarios. The center of inertia frequency (COIF) is selected to represent the overall system's frequency characteristic. By examining COIF deviation and the Rate of Change of Frequency (ROCOF) during contingency events, the inertia and damping parameters of the HESS are designed. Additionally, an adaptive inertia approach is incorporated to further reduce the SC capacity. The analysis of COIF dynamics under contingency with adaptive inertia is performed, and an analytical expression of COIF dynamics is derived. Subsequently, a sizing method for the SC and battery in the HESS, considering adaptive inertia, is proposed. The effectiveness of the proposed sizing method is verified through simulation results, demonstrating its suitability for optimizing the design of the hybrid energy storage system in the novel HESS configuration.

Development of NaCl-MgCl2-CaCl2 Ternary Salt for High-Temperature Thermal Energy Storage Using Machine Learning.

NaCl-MgCl2-CaCl2 eutectic ternary chloride salts are potential heat transfer and storage materials for high-temperature thermal energy storage. In this study, first-principles molecular dynamics simulation results were used as a data set to develop an interatomic potential for ternary chloride salts using a neural network machine learning method. Deep potential molecular dynamics (DPMD) simulations were performed to predict the microstructure and thermophysical properties of the NaCl-MgCl2-CaCl2 ternary salt. This work reveals that DPMD simulations can accurately calculate the microstructure and thermophysical properties of ternary chloride salts. The association strength of chloride ions and cations follows the order of Mg2+ > Ca2+ > Na+, and the coordination number decreases gradually with increasing temperature, indicating a progressively looser and more disordered molten structure. Furthermore, thermophysical properties, such as density, specific heat capacity, thermal conductivity, and viscosity, are in good agreement with the experimental measurements. Machine learning molecular dynamics will provide a feasible multivariate molten salt exploration method for the design of next-generation solar power plants and thermal energy storage systems.

Load decomposition: A conceptual framework for design and control of thermal energy storage systems in buildings

This work proposes a load decomposition framework for the characterization of thermal energy storage systems (TES) in buildings. This conceptual framework makes it possible to rapidly obtain an estimate of the required rating for the primary equipment and the storage device. The proposed approach employs mathematical methods from signal processing to break down the building load signal into two sub-signals: (a) a primary load provided by the primary production system, and (b) a balancing load provided by the storage system. This information is used to form a Pareto set of solutions that expresses the trade-off between the storage capacity and the primary system size, and hence, comprises the peak shaving potential of any given configuration. A simple decomposition method based on the concept of ”moving average” is tested within this framework on a representative energy model of an office building in the region of Montréal, Québec (QC). The Pareto set is shown to offer a wide range of design and operation solutions for peak shaving, from small water tanks to large underground reservoirs. The results provide clear evidence that TES system not only contributes to peak shaving and load shifting, but also to significantly reduce the primary production unit size.

Charging rate effect on overcharge-induced thermal runaway characteristics and gas venting behaviors for commercial lithium iron phosphate batteries

Increasing charging rate is an upgrading direction of electrochemical energy storage, which might induce more heat accumulation, posing a higher risk to cause the battery thermal runaway (TR). Driven by this, an experimental investigation was carried out to study the characteristics of TR and gas venting behaviors in commercial lithium iron phosphate (LFP) batteries that were induced by overcharging under different rates. As the charging rate increases, the growth rate of lithium dendrites accelerates, resulting in the earlier formation of large-scale short circuits and a rapid transition to the next stage of the TR chain reaction. However, the temperature rise and the total heat does not increase in proportion to the charge rates. The electrolyte also accelerates its decomposition, and the reaction between the electrolyte and lithium is the main reason of overcharge heat accumulation. It is worth noting that the charging rate for overcharging is positively correlated with the TR violence of batteries and the explosion risk of the ejected gas. The main gases emitted are H2, CO, and CO2 and various alkanes. Specifically, the content of H2 gas increases significantly with the increase of charging rate. And the H2 contents for 2C, 1.5C and 1C correspond to 61%, 53% and 50%, respectively. The rapid growth of lithium dendrites results in a significant increase in H2 generation and earlier capture. This is accompanied by a higher impact pressure and a lower explosion limit (LEL) of the combustible gas mixture, indicating a severer explosion risk. In short, by comparing the TR characteristics and gas products of LFP batteries with different charging rates, which is of great significance for the fire extinguishing design and emergency response of energy storage systems.

Experimental and Theoretical Analysis of Immersion Cooling of a Li-Ion Battery Module

Abstract Overheating of Li-ion cells and battery packs is an ongoing technological challenge for electrochemical energy conversion and storage, including in electric vehicles. Immersion cooling is a promising thermal management technique to address these challenges. This work presents experimental and theoretical analysis of the thermal and electrochemical impact of immersion cooling of a small module of Li-ion cells. Significant reduction in both surface and core temperature due to immersion cooling is observed, consistent with theoretical and simulation models developed here. However, immersion cooling is also found to result in a small but non-negligible increase in capacity fade of the cells. A number of hypotheses are formed and systematically tested through a comparison of experimental measurements with theoretical modeling and simulations. Electrochemical Impedance Spectroscopy measurements indicate that the accelerated cell aging due to immersion cooling is likely to be due to enhanced lithium plating. Therefore, careful consideration of the impact of immersion cooling on long-term performance may be necessary. The results presented in this work quantify both thermal and electrochemical impacts of a promising thermal management technique for Li-ion cells. These results may be of relevance for design and optimization of electrochemical energy conversion and storage systems.

An investigation and multi-criteria optimization of an innovative compressed air energy storage

Compressed air energy storage, a well-known technique for energy storage purposes on a large scale, has recently attracted substantial interest due to the development and long-term viability of smart grids. The current research focus on the design and thorough examination of a compressed air energy storage system utilizing a constant pressure tank. Various aspects, including energy, exergy, economic, and exergoeconomic factors, have been extensively investigated in this study. The goal of the referenced design is to maximize the utilization of air's energy stored in the tank, minimize exergy destruction, enhance production capacity and energy storage density, optimize system performance, and recover waste heat efficiently. Additionally, through the utilization of artificial neural networks and genetic algorithms, this study provides an analysis of optimal operational conditions, taking into account both thermodynamic and economic performance considerations. The referenced system, which stores 209 MWh of excess power from the grid as compressed air and heat throughout off-peak times and utilizes it to produce 137 MWh of electrical power during peak demand periods, demonstrates remarkable performance compared to the conventional storage methods. The findings indicate that the total electrical efficiency, round trip efficiency, and exergy round trip efficiency of the referenced system are equal to 65.63 %, 68.28 %, and 66.01 %, respectively. The total cost of the products of the system is 21.15 $/GJ, while exhibiting a value of 190.4 $/MWh for its levelized cost of electricity. The system's payback period is approximately 5.11 years, and the ultimate profit amounts to around $40 million.

Optimal Design and Analysis of a Hybrid Hydrogen Energy Storage System for an Island-Based Renewable Energy Community

Installations of decentralised renewable energy systems (RES) are becoming increasing popular as governments introduce ambitious energy policies to curb emissions and slow surging energy costs. This work presents a novel model for optimal sizing for a decentralised renewable generation and hybrid storage system to create a renewable energy community (REC), developed in Python. The model implements photovoltaic (PV) solar and wind turbines combined with a hybrid battery and regenerative hydrogen fuel cell (RHFC). The electrical service demand was derived using real usage data from a rural island case study location. Cost remuneration was managed with an REC virtual trading layer, ensuring fair distribution among actors in accordance with the European RED(III) policy. A multi-objective genetic algorithm (GA) stochastically determines the system capacities such that the inherent trade-off relationship between project cost and decarbonisation can be observed. The optimal design resulted in a levelized cost of electricity (LCOE) of 0.15 EUR/kWh, reducing costs by over 50% compared with typical EU grid power, with a project internal rate of return (IRR) of 10.8%, simple return of 9.6%/year, and return on investment (ROI) of 9 years. The emissions output from grid-only use was reduced by 72% to 69 gCO2e/kWh. Further research of lifetime economics and additional revenue streams in combination with this work could provide a useful tool for users to quickly design and prototype future decentralised REC systems.

Performance improvement through nonlinear control design and power management of a grid-connected wind-battery hybrid energy storage system

This paper presents a study on the application of nonlinear control and optimal power management techniques in a grid-connected wind energy conversion system with battery storage. The objective is to efficiently supply power to a load while considering performance constraints. The energy system under investigation comprises a wind turbine, battery, AC-grid, and load. Power is delivered to the load through various converters and a DC-link. However, the intermittent nature of wind energy and frequent load fluctuations can negatively impact the battery's lifetime and charging performance. To address these challenges, a nonlinear controller and a novel energy management system are designed. The energy management system generates multiple energy flow scenarios to achieve equilibrium in energy distribution between the load and energy sources. This equilibrium aims to minimize overall system costs, ensure DC-grid stability, and enhance power quality. Two distinct operation modes are identified: i) MPPT mode, which utilizes an optimizer to maximize power extraction, and ii) adaptive power point tracking (APPT) mode, which considers demand-driven production and the state of charge (SOC) of the storage system. The convergence of the closed-loop control is formally analyzed, and simulation results confirm the improved performance of the proposed multi-criteria design for energy management.