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Full- and reduced-order observers have been used in many engineering applications, particularly for energy systems. Applications of observers to energy systems are twofold: (1) the use of observed variables of dynamic systems for the purpose of feedback control and (2) the use of observers in their own right to observe (estimate) state variables of particular energy processes and systems. In addition to the classical Luenberger-type observers, we will review some papers on functional, fractional, and disturbance observers, as well as sliding-mode observers used for energy systems. Observers have been applied to energy systems in both continuous and discrete time domains and in both deterministic and stochastic problem formulations to observe (estimate) state variables over either finite or infinite time (steady-state) intervals. This overview paper will provide a detailed overview of observers used for linear and linearized mathematical models of energy systems and review the most important and most recent papers on the use of observers for nonlinear lumped (concentrated)-parameter systems. The emphasis will be on applications of observers to renewable energy systems, such as fuel cells, batteries, solar cells, and wind turbines. In addition, we will present recent research results on the use of observers for distributed-parameter systems and comment on their actual and potential applications in energy processes and systems. Due to the large number of papers that have been published on this topic, we will concentrate our attention mostly on papers published in high-quality journals in recent years, mostly in the past decade. [ABSTRACT FROM AUTHOR]

Described here is the production and characterization of a scalable method to produce 3D structured lithium ion battery anodes using free-standing papers of porous silicon nanowires (Si-NW) and graphene nanoribbons (GNRs). Using simple filtration methods, GNRs and Si-NWs can be entangled into a mat thereby forming Si-NW GNR papers. This produces anodes with high gravimetric capacity (up to 2500 mA h g−1) and high areal and volumetric capacities (up to 11 mA h cm−2 and 3960 mA h cm−3). The compact structure of the anode is possible since the GNR volume occupies a high proportion of empty space within the composite paper. These Si-NW/GNR papers have been cycled for over 300 cycles, exhibiting a stable life cycle. Combined with LiCoO2 nanowires, a full battery is produced with high energy density (386 Wh kg−1), meeting requirements for high performance devices. [ABSTRACT FROM AUTHOR]

Modular multilevel converters with non-sinusoidal ac voltage output can reduce cost and volume in medium-voltage-connected electric vehicle battery charging applications. The use of full-bridge submodules in such converters enables single-stage ac/ac voltage conversion, allowing a medium-voltage grid to be directly connected to a medium-frequency isolation transformer. The application of a square wave voltage at the medium-frequency transformer's single-phase port enhances the converter's efficiency and power density in comparison to a sinusoidal voltage. This paper presents the analysis and modelling of a modular multilevel converter, comparing its operation with sinusoidal and square wave output voltages. A single control scheme for both output voltage waveforms is proposed for the three-phase and single-phase ac currents, circulating currents, and the energy stored in the submodule capacitors. The control strategy of the three-phase and single-phase port currents is verified through simulation and experiments using a scaled-down prototype, thereby validating its suitability for high-power bidirectional battery chargers. [ABSTRACT FROM AUTHOR]

Many policy documents have called for a higher degree of circularity in the use of critical raw materials (CRMs). This paper examines how this objective has been translated from EU policy to legislation. The analysis presents three regulatory strategies used in the current framework to promote the recovery of CRMs: indirect methods, direct regulation of single CRMs, and collective regulation of all CRMs. The indirect approach has struggled to effectively target CRMs. Direct regulation of single CRMs provides an alternative, but other than the new Batteries Regulation no legislation has introduced strong obligations requiring recovery of single CRMs. The proposed CRM Regulation would codify the main concepts relevant for governing and regulating CRMs collectively. While the legislation would create a solid foundation for these processes, its failure to put forward immediate or long-term solutions to CRM recovery remains a serious shortcoming. The present research indicates that the current legal obligations lack a focus on the recovery of CRMs, with concrete obligations to this end limited. [ABSTRACT FROM AUTHOR]

Due to the volatile nature of renewable energy sources (RES), energy storage systems (ESS) are the primary impetus for increased dependence on RES in current power networks. Because of their quick responsiveness and rapid transition from charge to discharge in less than 1 ms, batteries are necessary even in the presence of alternative storage devices. Lithium-ion batteries (LIBs) have demonstrated their viability as ESS for RES. Given the significance of LIBs, it was vital to correctly and effectively quantify their costs in energy systems. Most studies did not offer a true real-world assessment of these batteries' aging but instead averaged their performance indices, which vary substantially depending on the system's working circumstances such as temperature, voltage, state of charge, and current level. Failure to use precise values for each charging/discharging operation might result in disastrous judgments and future techno-economic issues. This paper provides a novel and highly accurate piecewise modeling of LIBs for each charging and discharging operation based on real-world operational conditions. This novel aging model is used for calculating hourly aging and its impact on energy costs. The musical chair algorithm (MCA) is used to determine the optimal parameters' values of the LIB's model and the appropriate size of autonomous hybrid RES. When compared to other optimization techniques, the findings of optimal parameter determination using MCA revealed an 80% reduction in convergence time and better accuracy. The novel proposed aging model of the batteries predicts a 60% cost share of the battery, meanwhile, the existing strategy predicts 51% only. The levelized cost of energy is $0.1291/kWh and $0.0731/kWh for the new proposed aging model and existing strategy, respectively. [ABSTRACT FROM AUTHOR]

Mathematical models of energy systems have been mostly represented by either linear or nonlinear ordinary differential equations. This is consistent with lumped-parameter dynamic system modeling, where dynamics of system state variables can be fully described only in the time domain. However, when dynamic processes of energy systems display both temporal and spatial evolutions (as is the case of distributed-parameter systems), the use of partial differential equations is necessary. Distributed-parameter systems, being described by partial differential equations, are mathematically (and computationally) much more difficult for modeling, analysis, simulation, and control. Despite these difficulties in recent years, quite a significant number of papers that use partial differential equations to model and control energy processes and systems have appeared in journal and conference publications and in some books. As a matter of fact, distributed-parameter systems are a modern trend in the areas of control systems engineering and some energy systems. In this overview, we will limit our attention mostly to renewable energy systems, particularly to partial differential equation modeling, simulation, analysis, and control papers published on fuel cells, wind turbines, solar energy, batteries, and wave energy. In addition, we will indicate the state of some papers published on tidal energy systems that can be modelled, analyzed, simulated, and controlled using either lumped or distributed-parameter models. This paper will first of all provide a review of several important research topics and results obtained for several classes of renewable energy systems using partial differential equations. Due to a substantial number of papers published on these topics in the past decade, the time has come for an overview paper that will help researchers in these areas to develop a systematic approach to modeling, analysis, simulation, and control of energy processes and systems whose time–space evolutions are described by partial differential equations. The presented overview was written after the authors surveyed more than five hundred publications available in well-known databases such as IEEE, ASME, Wiley, Google, Scopus, and Web of Science. To the authors' best knowledge, no such overview on PDEs for energy systems is available in the scientific and engineering literature. Throughout the paper, the authors emphasize novelties, originalities, and new ideas, and identify open problems for future research. To achieve this goal, the authors reviewed more than five hundred journal articles and conference papers. [ABSTRACT FROM AUTHOR]

The rational combination of conductive nanocarbon with sulfur leads to the formation of composite cathodes that can take full advantage of each building block; this is an effective way to construct cathode materials for lithium-sulfur (Li-S) batteries with high energy density. Generally, the areal sulfur-loading amount is less than 2.0 mg cm−2, resulting in a low areal capacity far below the acceptable value for practical applications. In this contribution, a hierarchical free-standing carbon nanotube (CNT)-S paper electrode with an ultrahigh sulfur-loading of 6.3 mg cm−2 is fabricated using a facile bottom-up strategy. In the CNT-S paper electrode, short multi-walled CNTs are employed as the short-range electrical conductive framework for sulfur accommodation, while the super-long CNTs serve as both the long-range conductive network and the intercrossed mechanical scaffold. An initial discharge capacity of 6.2 mA·h cm−2 (995 mA·h g−1), a 60% utilization of sulfur, and a slow cyclic fading rate of 0.20%/cycle within the initial 150 cycles at a low current density of 0.05 C are achieved. The areal capacity can be further increased to 15.1 mA·h cm−2 by stacking three CNT-S paper electrodes-resulting in an areal sulfur-loading of 17.3 mg cm−2-for the cathode of a Li-S cell. The as-obtained free-standing paper electrode are of low cost and provide high energy density, making them promising for flexible electronic devices based on Li-S batteries. [ABSTRACT FROM AUTHOR]

To support increasing renewable capacity for a net-zero future, energy storage will play a key role in maintaining grid stability. In this paper, all current and near-future energy storage technologies are compared for three different scenarios: (1) fixed electricity buy-in price, (2) market-based electricity buy-in price, and (3) energy storage integrated into a fully renewable electricity system. In the first part of this study, an algorithm is devised to simulate strategic buy-in of electricity for energy storage. This analysis yields a qualitative decision-making tool for a given energy storage duration and size. Building upon the first part's findings, an integration study gives insight into expected power prices and expected storage size in a typical northwestern European fully renewable energy system. The integration study shows significant need for electricity storage with durations spanning from one to several days, typically around 40 h. Pumped Hydro Storage and Pumped Thermal storage surface as the best options. The overall levelized costs of storage are expected to be in the USD 200–500/MWh range. Integration of storage with renewables can yield a system-levelized cost of electricity of about USD 150/MWh. Allowing flexibility in demand may lower the overall system-levelized cost of electricity to USD 100/MWh. [ABSTRACT FROM AUTHOR]

Li–Al–O thin films synthesized via the reactive magnetron co-sputtering have the potential to act as solid-state electrolytes in micro-batteries. In this paper, the constant RF power (155 W) and variable DC power (20–50 W) were applied to lithium (Li) and aluminum (Al) metal targets, respectively, in Ar/O 2 atmosphere to produce films with adequate ionic conductivity. The influence of DC sputtering power on the composition, microstructure, band gap energy, ionic conductivity, and dielectric loss of films were studied in detail. X-ray photoelectron spectroscopy (XPS) showed a shift of the Li 1s peak towards higher binding energy with increasing DC power. X-ray diffraction (XRD) spectra confirmed the amorphous state for all as-deposited films, while the post-annealed films at 950 °C contain the γ-LiAlO 2 phase. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) images revealed that the increasing DC power had a significant impact on the film morphology, enlarging grain size and increasing surface roughness. Energy dispersive X-ray (EDX) spectroscopy showed that increasing the DC power increased the Al content. The optical properties were examined by ultraviolet–visible (UV–vis) spectroscopy, which indicated that increasing the Al content led to a blue shift of the absorption edge and an increase in the band gap energy (5.40–5.68 eV). Increasing the DC power resulted in an improvement of room-temperature conductivity by two orders of magnitude (∼2.85 × 10−9 S cm−1) and a decrease in the activation energy from 0.54 eV to 0.32 eV. These results suggest that composition and microstructure significantly affect the ionic transport in co-sputtered Li–Al–O films. [ABSTRACT FROM AUTHOR]

Li–Al–O thin films synthesized via the reactive magnetron co-sputtering have the potential to act as solid-state electrolytes in micro-batteries. In this paper, the constant RF power (155 W) and variable DC power (20–50 W) were applied to lithium (Li) and aluminum (Al) metal targets, respectively, in Ar/O 2 atmosphere to produce films with adequate ionic conductivity. The influence of DC sputtering power on the composition, microstructure, band gap energy, ionic conductivity, and dielectric loss of films were studied in detail. X-ray photoelectron spectroscopy (XPS) showed a shift of the Li 1s peak towards higher binding energy with increasing DC power. X-ray diffraction (XRD) spectra confirmed the amorphous state for all as-deposited films, while the post-annealed films at 950 °C contain the γ-LiAlO 2 phase. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) images revealed that the increasing DC power had a significant impact on the film morphology, enlarging grain size and increasing surface roughness. Energy dispersive X-ray (EDX) spectroscopy showed that increasing the DC power increased the Al content. The optical properties were examined by ultraviolet–visible (UV–vis) spectroscopy, which indicated that increasing the Al content led to a blue shift of the absorption edge and an increase in the band gap energy (5.40–5.68 eV). Increasing the DC power resulted in an improvement of room-temperature conductivity by two orders of magnitude (∼2.85 × 10−9 S cm−1) and a decrease in the activation energy from 0.54 eV to 0.32 eV. These results suggest that composition and microstructure significantly affect the ionic transport in co-sputtered Li–Al–O films. [ABSTRACT FROM AUTHOR]

Global society is significantly speeding up the adoption of renewable energy sources and their integration into the current existing grid in order to counteract growing environmental problems, particularly the increased carbon dioxide emission of the last century. Renewable energy sources have a tremendous potential to reduce carbon dioxide emissions because they practically never produce any carbon dioxide or other pollutants. On the other hand, these energy sources are usually influenced by geographical location, weather, and other factors that are of stochastic nature. The battery energy storage system can be applied to store the energy produced by RESs and then utilized regularly and within limits as necessary to lessen the impact of the intermittent nature of renewable energy sources. The main purpose of the review paper is to present the current state of the art of battery energy storage systems and identify their advantages and disadvantages. At the same time, this helps researchers and engineers in the field to find out the most appropriate configuration for a particular application. This study offers a thorough analysis of the battery energy storage system with regard to battery chemistries, power electronics, and management approaches. This paper also offers a detailed analysis of battery energy storage system applications and investigates the shortcomings of the current best battery energy storage system architectures to pinpoint areas that require further study. [ABSTRACT FROM AUTHOR]

Abstract: A flexible battery is printed on paper by screen-printing a zinc/carbon/polymer composite anode on one side of the sheet, polymerising a poly(3,4-ethylenedioxythiophene) (PEDOT) cathode on the other side of the sheet, and applying a lithium chloride electrolyte between the two electrodes. The PEDOT cathode is prepared by inkjet printing a pattern of iron(III)p-toluenesulfonate as a solution in butan-1-ol onto paper, followed by vapour phase polymerisation of the monomer. The electrolyte is prepared as a solution of lithium chloride and lithium hydroxide and also applied by inkjet printing on to paper, where it is absorbed into the sheet cross-section. Measurements on a zinc/carbon-PEDOT/air battery in a similar configuration on a polyethylene naphthalate substrate shows a discharge capacity of up to 1.4mAhcm−2 for an initial load of 2.5mg zinc, equivalent to almost 70% of the zinc content of the anode, which generates 0.8V at a discharge current of 500μA. By comparison, the performance of the paper-based battery is lower, with an open-circuit voltage of about 1.2V and a discharge capacity of 0.5mAhcm2. It appears that the paper/electrolyte combination has a limited ability to take up anode oxidation products before suffering a reduction in ionic mobility. The effects of different zinc/carbon/binder combinations, differences in application method for the zinc/carbon composite and various electrolyte compositions are discussed. [Copyright &y& Elsevier]

In this paper, balancing electricity production using renewable energy such as wind power, PV cells, hydropower, and CHP (combined heat and power) with biomass is carried out in relation to electricity consumption in primarily one major region in Sweden, SE-3, which contains 75% of the country's population. The time perspective is hours and days. Statistics with respect to power production and consumption are analyzed and used as input for power-balance calculations. How long periods are with low or high production, as well as the energy for charge and discharge that is needed to maintain a generally constant power production, is analyzed. One conclusion is that if the difference in production were to be completely covered with battery capacity it would be expensive, but if a large part of the difference were met by a shifting load it would be possible to cover the rest with battery storage in an economical way. To enhance the economy with battery storage, second-life batteries are proposed to reduce the capital cost in particular. Batteries are compared to hydrogen as an energy carrier. The efficiency of a battery system is higher than that of hydrogen plus fuel cells, but in general much fewer precious materials are needed with an H2/fuel-cell system than with batteries. The paper discusses how to make the energy system more robust and resilient. [ABSTRACT FROM AUTHOR]

Because of their extensive specific surface area, excellent charge transfer rate, superior chemical stability, low cost, and Earth abundance, nanostructured titanium dioxide (TiO2) arrays have been thoroughly explored during the past few decades. The synthesis methods for TiO2 nanoarrays, which mainly include hydrothermal/solvothermal processes, vapor-based approaches, templated growth, and top-down fabrication techniques, are summarized, and the mechanisms are also discussed. In order to improve their electrochemical performance, several attempts have been conducted to produce TiO2 nanoarrays with morphologies and sizes that show tremendous promise for energy storage. This paper provides an overview of current developments in the research of TiO2 nanostructured arrays. Initially, the morphological engineering of TiO2 materials is discussed, with an emphasis on the various synthetic techniques and associated chemical and physical characteristics. We then give a brief overview of the most recent uses of TiO2 nanoarrays in the manufacture of batteries and supercapacitors. This paper also highlights the emerging tendencies and difficulties of TiO2 nanoarrays in different applications. [ABSTRACT FROM AUTHOR]

This paper focuses on the design and use of a control system for a renewable energy production plant based on hydrogen. The proposed control system aims at ensuring the stability and smooth functionality of the plant, which consists of a (i) photovoltaic system connected to an electrolyzer through a battery, (ii) a DC/DC step down transformer, and (iii) an electrolyzer heat exchange system. In this study, solar irradiance is the main system input, and hydrogen production the main output. Since the system utilizes solar energy as input, it depends on the random input of solar irradiance, ambient temperature, and wind flow. Furthermore, the electrolyzer's functionality is subject to several operational variables including cell voltage, current, temperature, and pressure. The electrolyzer heat exchange system operates at specified water temperatures and flow rates. The DC/DC output voltage, and therefore the voltage supplied to the electrolyzer, is regulated by changing its duty cycle. To regulate hydrogen production in the renewable energy production plant, an efficient control system is required. Accordingly, in this work, a control system is designed accounting for three different electrolyzer technologies, alkaline, PEM (proton exchange membrane), and E-TAC (electrochemical - thermally activated chemical water splitting). Subsequently, the effectiveness of the control system is analyzed using Matlab and Simulink models. The main results indicate that the battery is a crucial element in the whole system as it supplies the necessary energy to the electrolyzer. By regulating the appropriate components, the proposed control system proved capable of minimizing power fluctuations and increasing system efficiency up to 20% depending on ambient conditions. Additionally, the results indicate E-TAC and PEM efficiencies 13% and 7% higher than alkaline, respectively. [Display omitted] • Design of a control system for three different electrolyzer technologies. • Use of control systems for electrolyzer voltage and heat exchange. • Photovoltaic system connected to an electrolytic one through a battery. • Proposed control system increases system efficiency up to 20%. [ABSTRACT FROM AUTHOR]

The industrial sector is not the one with the highest energy consumption but, together with, it represents the most, together with the transport sector, the most polluting ones. Photovoltaic Rooftop systems and battery energy storage systems are very strong candidates to include renewable energy, allowing greater grid autonomy and greenhouse gas mitigation. Therefore, this paper aims to outline it will be provided a methodology based on monitored data to analyze the potential of photovoltaic Rooftops with battery energy storage systems regarding self-consumption and self-sufficiency indices in the industrial sector. Direct self-consumption and self-sufficiency indices, either with or without storage, will be analyzed. In addition, the iso self-consumption and iso self-sufficiency curves are used, which allow us to evaluate the matching between the generation and consumption profiles considering either direct self-consumption or the use of batteries. In this sense, a large, medium, and small olive mill were selected in order to cover the entire spectrum of these industries. Olive mills are suitable candidates for the incorporation of photovoltaic systems since generation profiles match the consumption profiles. However, the size of these systems is highly dependent on the period of consumption to be faced. Regarding batteries, both during the harvest and off-harvest periods, the impact on self-sufficiency becomes significant, reaching increases of up to 10%, depending on the battery capacity used. [ABSTRACT FROM AUTHOR]

Sintered neodymium-iron-boron (NdFeB) magnets and lithium-ion (Li-ion) batteries are essential in a number of clean energy technologies such as electric vehicles and wind turbines. The United States (US) has some manufacturing capacity for Li-ion batteries and almost no capacity for producing sintered NdFeB magnets. As a result, the US imports significant quantities of these batteries and magnets. Trade statistics on imported batteries and magnets, however, include only those materials imported in the form of batteries and magnets (referred to here as reported imports) and exclude materials embedded in intermediate and final products such as hard disk drives, electric motors, electric vehicles, and wind turbines (referred to here as embedded imports). This paper develops original estimates of embedded imports of NdFeB magnets and Li-ion batteries, leading to a more complete picture of US imports than looking at reported imports alone. It estimates that more than 90% of NdFeB magnet imports were embedded in intermediate and final products in 2021. In contrast, more than 90% of Li-ion battery imports were in the form of the batteries themselves rather than embedded in intermediate and final products. [ABSTRACT FROM AUTHOR]

Wind turbines (WT) offer valuable environmentally friendly energy solutions, particularly for electricity generation, owing to their renewable nature. These renewable energy systems (RESs) present an indispensable solution for sites that are not associated with the electrical grid. However, their intermittent power generation, which can be more or less than that required by the load, due to variable wind patterns, poses a challenge. To overcome these weaknesses, the integration of robustly controlled storage systems is a good proposal as it enhances the stability of standalone applications in terms of voltages and powers. In this paper, an intelligent supervisory power control system is developed to manage the different components of the renewable energy generator (REG). A fuzzy logic proportional–integral PI controller is also introduced, in the permanent magnet synchronous generator (PMSG) and the batteries, to better regulate energy, compared to a conventional PI controller. The main objective of this study is to introduce a new control strategy to satisfy the energy requirement of the load. The configuration of the suggested control methodology consists of a fuzzy logic supervisor (FLS) elaborated to manage energy flows, ensuring equilibrium between production and consumption amidst weather and load changes. The presented control method was applied to an autonomous wind battery station, showcasing its ability to maintain energy supply, minimize fluctuations, and enhance stability. Simulation results, executed in MATLAB/Simulink, confirm the effectiveness of the proposed system under various scenarios of wind speed variability and storage system state of charge. [ABSTRACT FROM AUTHOR]

The design and manufacturing of energy storage system (ESS) are essential for human society development. India has made significant efforts to improve its energy storage infrastructure. The main elements for energy storage development are batteries i.e., lithium-ion batteries (LIB), lithium air batteries, etc. and supercapacitors. As the lithium resources are specifically located in China, Japan, USA, and Chile, to reduce the dependency on these countries for lithium-ion battery, India must think about alternative material. Sodium-ion battery (SIB) is at the forefront of the development, and it aims at providing low-cost devices less affected to resources. This review paper addresses the fundamental principles, structure and focused on the components of sodium-ion battery. This paper also helps to address the electrolytes used in sodium-ion battery with their design and modelling. Current research and future directions has been discussed in this article for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs), with their extraordinary combination of mechanical, electrical, and thermal properties, have emerged as a revolutionary class of nanomaterials with immense potential in energy storage and harvesting devices. Realizing this potential hinges on a fundamental challenge: the dispersion stability of CNTs within various matrices. This review paper provides a comprehensive exploration of the critical interplay between CNT dispersion stability and its far-reaching implications for the performance of energy storage and harvesting technologies. By delving into the underlying mechanisms of dispersion, the strategies to achieve stability, and the direct effects on device functionality, this review sheds light on the intricate relationship between nanotube dispersion and the advancement of energy-related applications. [ABSTRACT FROM AUTHOR]

In recent years, the development of implantable bioelectronics has garnered significant attention. With the continuous advancement of IoT and information technology, implantable bioelectronics can be utilized more effectively for health monitoring to enhance treatment outcomes, reduce healthcare costs, and improve quality of life. Implantable energy storage devices have been widely studied as critical components for energy supply. Conventional power sources are bulky, inflexible, and potentially contain materials that are dangerous to the body. Meanwhile, human tissues are soft, flexible, dynamic, and closed, which puts new requirements on energy storage devices to improve the safety, stability, and matching of implantable batteries or supercapacitors. Herein, recent advances in state‐of‐the‐art nonconventional power options for implantable electronics, specifically biocompatible, miniaturized, stretchable/deformable, biodegradable/bioresorbable, edible, and injectable energy storage devices, are reviewed in this paper. The material strategy and architectural design of the next‐generation implantable energy storage device are discussed, including the selection principle of electrolytes, the all‐in‐one structure design strategy, and the way to realize self‐charging. Finally, the challenges and prospects of emerging design strategies toward developing next‐generation implantable batteries and supercapacitors for the future are put forward. [ABSTRACT FROM AUTHOR]

With the introduction of automated driving, new requirements for the design and control of a vehicle powernet and powertrain arise, since the increasing level of driving automation shifts the responsibility for passengers’ safety from a driver towards automation system. Therefore, the functionality of the subsystems required for the automated transition to a standstill in case of a failure must be guaranteed. The work presented in this paper proposes a novel and generic system architecture for the energy management of a fail-operational powernet and powertrain in fault-free and failure case operation. The underlying control strategy is based on a concept enabling safety based range extension with the main goal to complete a driving mission at the safest possible location for the passengers. The proposed Energy Management System (EMS) approximates a driving trajectory to the destination based on route preview, which is then used for the dynamic optimization of the torque split in a powertrain with multiple motors. In this way, the total energy required for propulsion, which is also used as an input for the energy distribution, can be accurately predicted. The optimal distribution of the energy for the supply of safety-critical subsystems and powernet auxiliaries is then estimated by solving a mixed-integer optimization problem. If the desired driving mission cannot be completed, a three-level-degradation concept adapting the driving mission is applied. The individual modules of the EMS are presented in this paper and a system architecture enabling model predictive and adaptive energy distribution in a vehicle powertrain and powernet with automated fault reactions is proposed and exemplified with simulation results. [ABSTRACT FROM AUTHOR]

This research study presents the design of a mobile Android application which provides efficient PV sizing recommendations for residential users. The paper aims to promote the adoption of solar energy to meet energy demands for residential use, by providing accurate information to prospective renewable energy users via the development of an android application for the sizing of PV-battery systems. The study adopted a Design Science Research (DSR) methodology which employs models, techniques, and algorithms to create artifacts expected to meet specified sets of functional requirements. DSR provided stepwise processes for development of the application, validation, testing and evaluation. The evaluation of the android application's accuracy was presented in this paper, after extensive testing by experts and non-experts. Its performance showed that the feasibility of the application is suitable for potential users and professionals alike. The use of the developed mobile application could strengthen public-private partnerships that would promote widespread use of PV- battery system for residential applications. [ABSTRACT FROM AUTHOR]

State-of-charge (SoC) imbalance and bus voltage deviation are two of the main problems in autonomous dc microgrids. Based on this concern, this paper presents an improved dual-quadrant SoC weighted control strategy and a distributed optimization control method to achieve SoC balance, ensuring accurate power-sharing and bus voltage recovery. Firstly, this paper couples the injected/released power with the current SoC and observed average SoC value to weight the droop coefficient, which is based on the charge/discharge mode for the energy storage system. Then a secondary controller is designed based on distributed optimal control to eliminate the bus voltage deviation caused by the line impedance difference. The proposed optimal control method optimizes the average bus voltage to the nominal value and achieve accurate power-sharing by constructing the correlated variables and voltage independent intermediate variables exchanged among bulk energy storage units (ESUs). Since the voltage observer cannot accurately observe the true average bus voltage under the communication delay, the proposed distributed optimal control method without the voltage observer can ensure that the average bus voltage is optimized to the nominal value, thus improving the robustness of the control system. Finally, the correctness and effectiveness of the proposed method are verified in Simulink/MATLAB. [ABSTRACT FROM AUTHOR]

With the increasing installation of battery energy storage systems, the safety of high-energy-density battery systems has become a growing concern. Developing reliable battery fault diagnosis and fault warning algorithms is essential to ensure the safety of battery systems. After years of development, traditional fault diagnosis techniques based on three-dimensional information of voltage, current and temperature have gradually encountered bottlenecks. It is necessary to adopt a proactive approach by using mulitidimensional information to advance fault diagnosis techniques. This involves integrating advanced sensing technologies, collecting multidimensional data and uncovering subtle changes in battery behavior. This paper delves into the mechanisms and evolutionary paths of battery faults, with a specific focus on the multidimensional observable signals associated with different faults for enhanced safety strategy. Furthermore, the paper provides a comprehensive overview of potential applications of different sensors for multidimensional measurement in battery fault diagnosis. It also explores the future trends and research directions of the next generation of battery fault diagnosis techniques driven by multidimensional data collection and artificial intelligence algorithms. [Display omitted] • Enhanced safety through proactive, multidimensional fault diagnosis techniques. • Integration of advanced sensing tech for precise multidimensional data collection. • Uncovering subtle battery behavior changes for improved fault detection. • Specific focus on multidimensional signals to enhance safety strategies. • Future trends in battery fault diagnosis driven by AI and multidimensional data. [ABSTRACT FROM AUTHOR]

As the world strives to achieve a sustainable future, the exploration of alternative and renewable raw materials for energy storage and energy conversion has gained significant attention. A growing trend on "Waste to Energy" approach has attained prominence. Accordingly, chicken eggshells, a residual from poultry industry, have emerged as a promising candidate due to their abundant availability, low cost, and unique physical and chemical properties. This review article presents an overview of recent advancements in utilizing eggshell waste for energy storage and energy conversion applications. It discusses the transformation of eggshells usage into functional materials, along with their performance in various energy-related applications. The potential of eggshell-based materials in improving energy efficiency and reducing environmental impact is highlighted, providing insights into the future prospects of this sustainable resource. [Display omitted] • Relevance to Sustainability: The review article addresses the global imperative of achieving a sustainable future, making it highly relevant to current environmental concerns. • Focus on Alternative Materials: The review explores the use of alternative and eco-friendly materials for energy storage and conversion. • Waste to Energy Trend: The "Waste to Energy" approach, which is gaining prominence worldwide, is at the core of this review paper, showcasing its relevance in addressing waste management and energy challenges simultaneously. • Diverse Energy Storage Applications: The review explores a wide range of energy storage applications, including capacitors, batteries, and other devices. • Promising Energy Conversion Applications: The paper discusses energy conversion applications such as fuel cells and hydrogen production. [ABSTRACT FROM AUTHOR]

Magnetic induction is widely used as a non-destructive technique to detect and classify metal objects over a range of applications. This paper applies magnetic induction spectroscopy (MIS) as a technique to classify non-ferrous metals within shredded metal waste streams on a moving conveyor. The magnetic response of the metal piece as it passes over the sensor is used to predict the metal, where the measured complex impedance components are used as features for the machine learning models. MIS performs well, even when surface contaminants are present, compared to other techniques that require the metal pieces to be cleaned; this saves time and reduces cost when large amounts of surface contamination are present in a waste stream, such as biomass incinerator metals. MIS allows for a lower cost system when compared to X-ray and sink-float methods with a high throughput, which makes it an economical approach. [ABSTRACT FROM AUTHOR]

The paper presents modern technologies of electrochemical energy storage. The classification of these technologies and detailed solutions for batteries, fuel cells, and supercapacitors are presented. For each of the considered electrochemical energy storage technologies, the structure and principle of operation are described, and the basic constructions are characterized. Values of the parameters characterizing individual technologies are compared and typical applications of each of them are indicated. Selected characteristics illustrating properties of the presented electrochemical energy storage devices are also shown. The advantages and disadvantages of the considered electrochemical energy storage devices and typical areas of their application are indicated. In addition, new, constantly developing technologies, not yet commercially available, are mentioned. Examples of existing energy storage solutions using the discussed technologies on the example of electric cars or storage systems in the world are given. [ABSTRACT FROM AUTHOR]

Untethered robots carry their own power supply in the form of a battery pack, which has a crucial impact on the robot's performance. Although battery technologies are richly studied and optimized for applications such as electric vehicles, computers and smartphones, they are often a mere afterthought in the design process of a robot system. This tutorial paper proposes criteria to evaluate the suitability of different battery technologies for robotic applications. Taking into consideration the requirements of different applications, the capabilities of relevant battery technologies are evaluated and compared. The tutorial also discusses current limitations and new technological developments, pointing out opportunities for interdisciplinary research between the battery technology and robotics communities. [ABSTRACT FROM AUTHOR]

It is no secret that graphene, a two-dimensional single-layered carbon atom crystal lattice, has drawn tremendous attention due to its distinct electronic, surface, mechanical, and optoelectronic properties. Graphene also has opened up new possibilities for future systems and devices due to its distinct structure and characteristics which has increased its demand in a variety of applications. However, scaling up graphene production is still a difficult, daunting, and challenging task. Although there is a vast body of literature reported on the synthesis of graphene through conventional and eco-friendly methods, viable processes for mass graphene production are still lacking. This review focuses on the variety of unwanted waste materials, such as biowastes, coal, and industrial wastes, for producing graphene and its potential derivatives. Among the synthetic routes, the main emphasis relies on microwave-assisted production of graphene derivatives. In addition, a detailed analysis of the characterization of graphene-based materials is presented. This paper also highlights the current advances and applications through the recycling of waste-derived graphene materials using microwave-assisted technology. In the end, it would alleviate the current challenges and forecast the specific direction of waste-derived graphene future prospects and developments. [ABSTRACT FROM AUTHOR]

The diffusion of electric vehicles will be strongly related to the capacity to charge them in short times. To do so, the necessity of widespread fast charging stations arises. However, their intermittent demand represents a challenging load for grid operators. In order to relieve their impact on the electrical grid operation, integrating storage systems in the charging stations represents a potential solution, although it complicates the overall system management. Moreover, standard converter architectures for the MV grid interface require the installation of bulky transformers and filters. In order to cope with the mentioned problems, this paper proposes an ultra-fast charging station topology based on a modular multilevel converter (MMC) structure and dual-active bridge (DAB) converters. Thanks to the multilevel converter properties, the proposed charging station can be directly interfaced with the MV grid without requiring transformers or filters. Additionally, exploiting the degree of freedom in the converter control system, such as circulating components, offers uneven power distribution among the converter submodules that can be managed. Along with the MMC control strategy, the article addresses a straightforward methodology to select the main parameters of the DAB converter as a function of the involved grid power and circulating power contributions, with the primary goal of obtaining a trade-off between internal balancing performances and a broad soft-switching region without incurring in converter oversizing. The effectiveness of the proposed charging station is finally discussed through numerical simulations, where its behavior during a power demand cycle is analyzed. [ABSTRACT FROM AUTHOR]

Purpose: Few case studies in the literature report on adult patients with intentional foreign body ingestion. Prisoners deliberately ingest foreign bodies, such as cylindrical alkaline batteries and razor blades, to achieve hospitalization or commit suicide. The purpose of this paper is to present a case of deliberate ingestion of batteries and razor blades by an inmate. Design/methodology/approach: The authors present a case of an incarcerated man in Greece, who intentionally ingested three cylindrical alkaline batteries and three razor blades wrapped in aluminum foil. Findings: The patient was treated conservatively with serial radiographs and was subsequently discharged without complication. This paper discusses the complications and examine the current guidelines available. Originality/value: To best of authors' knowledge, this is the first report of a simultaneous ingestion of batteries and razor blades. [ABSTRACT FROM AUTHOR]

This paper presents a decomposed co-design optimization framework for an electric vehicle powertrain equipped with a Continuously Variable Transmission (CVT). We jointly design the sizes of the powertrain components and the energy management strategy, considering the design and the dynamics of the transmission. Specifically, we divide the resulting nonlinear optimization problem into separate hierarchical optimization subproblems leveraging the concept of Analytical Target Cascading (ATC). Furthermore, we compare the proposed decomposition-based strategy with a centralized approach, in which we solve the same problem, and show that the method presented in this paper can be a potential alternative to a centralized optimization formulation for solving the large-scale, complex integrated plant and control system design. Finally, we compare the resulting performance of using a CVT on the vehicle total-cost-of-ownership with that equipped with a Fixed-Gear Transmission (FGT), which is what is commonly implemented in current electric vehicles. Our results show that by jointly optimizing the design of the transmission along with the control strategy, the CVT yields a lower energy consumption and total-cost-of-ownership compared to that of the FGT. [ABSTRACT FROM AUTHOR]

Hybrid Renewable Energy Sources (HRES) integrated into a microgrid (MG) are a cost-effective and convenient solution to supply energy to off-grid and rural areas in developing countries. This research paper focuses on the optimization of an HRES connected to a stand-alone microgrid system consisting of photovoltaics (PV), wind turbines (WT), batteries (BT), diesel generators (DG), and inverters to meet the energy demand of fifteen residential housing units in the city of Djelfa, Algeria. In this context, the multiobjective salp swarm algorithm (MOSSA), which is among the latest nature-inspired metaheuristic algorithms recently introduced for hybrid microgrid system (HMS) optimization, has been proposed in this paper for solving the optimization of an isolated HRES. The proposed multiobjective optimization problem takes into account the cost of energy (COE) and loss of power supply probability (LPSP) as objective functions. The proposed approach is applied to determine three design variables, which are the nominal power of photovoltaic, the number of wind turbines, and the number of battery autonomy days considering higher reliability and minimum COE. In order to perform the optimum size of HMG, MOSSA is combined with a rule-based energy management strategy (EMS). The role of EMS is the coordination of the energy flow between different system components. The effectiveness of using MOSSA in addressing the optimization issue is investigated by comparing its performance with that of the multiobjective dragonfly algorithm (MODA), multiobjective grasshopper optimization algorithm (MOGOA), and multiobjective ant lion optimizer (MOALO). The MATLAB environment is used to simulate HMS. Simulation results confirm that MOSSA achieves the optimum system size as it contributed 0.255 USD/kW h of COE and LPSP of 27.079% compared to MODA, MOGOA, and MOALO. In addition, the optimization results obtained using the proposed method provided a set of design solutions for the HMS, which will help designers select the optimal solution for the HMS. [ABSTRACT FROM AUTHOR]

This paper proposes a dynamic valuation framework to determine the opportunity value of battery capacity degradation in grid applications based on the internal degradation mechanism and utilization scenarios. The proposed framework follows a dynamic programming approach and includes a piecewise linear value function approximation solution that solves the optimization problem over a long planning horizon. The paper provides two case studies on price arbitrage and frequency regulation using real market and system data to demonstrate the broad applicability of the proposed framework. Results show that the battery lifetime value is critically dependent on both the external market environment and its internal state of health. On the grid service side, results show that second-life batteries can provide more than 50% of the value compared to new batteries, and frequency regulation provides two times more revenue than price arbitrage throughout the battery lifetime. [ABSTRACT FROM AUTHOR]

We present the development of a novel smart ink pen instrumented with force and motion sensors designed for the quantitative and ecological assessment of daily-life handwriting. This work aims at testing the pen’s sensors and algorithms and the use of the smartpen to detect age-related changes in writing and tremor parameters during daily-life handwriting. A comparison against reference instruments was carried out to validate the pen tip force during static and dynamic conditions, the pen’s tilt angle, and the algorithm for the segmentation of the force signal into strokes. The smartpen was tested on 43 healthy adults divided into three age groups (young, middle-old, and old) during unconstrained handwriting on paper. The validation of the pen’s sensors and algorithms reported excellent results. A solid test–retest reliability was found in the writing and tremor indicators extracted from both young and old adults. As for the age-related analysis, the older age groups were characterized by an increase of temporal writing measures, a more uniform writing pressure, and more repetitive and predictable tremor oscillation components. The greatest accomplishment of our smart ink pen is the ability to combine the advantages of the digitizing tablet technology with the natural “feel,” the ease of use, and the ecological validity of the traditional pen-and-paper approach. The proposed solution represents an important step toward a simple, ecologically valid, reliable quantitative assessment of daily-life handwriting. Our smartpen is particularly suitable for daily-life telemonitoring applications in a number of important health-related fields. [ABSTRACT FROM AUTHOR]

Generation dispatching is a challenge in islanded microgrids due to the operational and economic restrictions in isolated zones. Furthermore, the impact of usual operational network changes in topology, load demand, and generation availability may become significant considering the grid size. This research paper presents a detailed multiple cost function modeling methodology of an optimal power flow algorithm applied to a non-interconnected zone in Colombia. The optimal power flow (OPF) formulation includes cost functions related to renewable resources as presented in the isolated zone and a complete model of the charging and discharging of batteries. Additionally, the flexibility of the proposal is tested using three different network topologies with a characteristic daily load curve from the zone. The main contribution of this paper lies in the implementation of an optimal power flow including cost functions of renewable sources for isolated microgrids. A test case for a non-interconnected zone in Colombia is performed for various operation cases. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) have attracted enormous attention in recent years due to their potentials in mitigating energy crisis and air pollutions. However, the long battery charging time and lack of sufficient charging infrastructure highly restrict the popularization of EVs. In this context, it is promising to establish battery charging and swapping systems (BCSSs) based on the concept of battery swapping services. To optimally achieve the combined operation of BCSSs, this paper proposes a hybrid swapped battery charging and logistics dispatch model in continuous time domain. Identifying the special structure of the mathematical models of the two problems, this paper innovatively formulated the swapped battery charging strategy as the rectangle packing problem and the battery logistics model as the vehicle routing problem. The two models are closely linked by the delivery time of transporting the well-charged batteries from battery charging stations to battery swapping stations. A hybrid optimal operation model of BCSSs is further formulated as a mixed-integer linear programming model by incorporating the interaction between the battery charging and battery logistics. Finally, case studies are conducted on several BCSSs and numerical results validate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

In this paper, we report an ab initio study of a composite material based on Ti2C and borophene B12 as an anode material for magnesium-ion batteries. The adsorption energy of Mg, specific capacitance, electrical conductivity, diffusion barriers, and open-circuit voltage for composite materials are calculated as functions of Mg concentration. It is found that the use of Ti2C as a substrate for borophene B12 is energetically favorable; the binding energy of Ti2C with borophene is −1.87 eV/atom. The translation vectors of Ti2C and borophene B12 differ by no more than 4% for in the X direction, and no more than 0.5% in the Y direction. The adsorption energy of Mg significantly exceeds the cohesive energy for bulk Mg. The energy barrier for the diffusion of Mg on the surface of borophene B12 is ~262 meV. When the composite surface is completely covered with Mg ions, the specific capacity is 662.6 mAh g−1 at an average open-circuit voltage of 0.55 V (relative to Mg/Mg+). The effect of reducing the resistance of borophene B12 upon its binding to Ti2C is established. The resulting electrical conductivity of the composite Ti16C8B40 is 3.7 × 105 S/m, which is three times higher than the electrical conductivity of graphite. Thus, a composite material based on Ti2C and borophene B12 is a promising anode material for magnesium-ion batteries. [ABSTRACT FROM AUTHOR]

Energy is very important in daily life. The smart power system provides an energy management system using various techniques. Among other load types, campus microgrids are very important, and they consume large amounts of energy. Energy management systems in campus prosumer microgrids have been addressed in different works. A comprehensive study of previous works has not reviewed the architecture, tools, and energy storage systems of campus microgrids. In this paper, a survey of campus prosumer microgrids is presented considering their energy management schemes, optimization techniques, architectures, storage types, and design tools. The survey is comprised of one decade of past works for a true analysis. In the optimization techniques, deterministic and metaheuristic methods are reviewed considering their pros and cons. Smart grids are being installed in different campuses all over the world, and these are considered the best alternatives to conventional power systems. However, efficient energy management techniques and tools are required to make these grids more economical and stable. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid renewable energy system (RES) including wind and photovoltaic (PV) power sources. The wind energy subsystem (WES) consists of a squirrel-cage induction generator (SCIG) driven by a variable-speed wind turbine (WT) and corresponding power electronic converter, by means of which a speed-sensorless indirect-rotor-field-oriented control of the SCIG is implemented. The outputs of both the WES and PV power source rated 1.5 kW and 3.5 kW, respectively, are connected to the DC bus, with the quasi-Z-source inverter (qZSI) acting as an interlinking converter between the DC bus and the AC grid/load. An advanced pulse-width-modulation scheme is applied to reduce the qZSI switching losses. The considered RES can operate both in grid-tie and island operation, whereas the battery storage system—integrated within the qZSI impedance network—enables more efficient energy management. The proposed control scheme includes successively executed algorithms for the optimization of the WES and PV power outputs under varying atmospheric conditions. A perturb-and-observe PV optimization algorithm is executed first due to the significantly faster dynamics and higher-rated power of the PV source compared to the WES. The WES optimization algorithm includes two distinct fuzzy logic optimizations: one for extraction of the maximum wind power and the other for minimization of the SCIG losses. To reduce the number of the required sensors, all three MPPT algorithms utilize the same input variable—the qZSI's input power—thus increasing the system's reliability and reducing the cost of implementation. The performance of the proposed hybrid RES was experimentally evaluated over wide ranges of simulated atmospheric conditions in both the island and grid-tie operation. [ABSTRACT FROM AUTHOR]

The high interfacial resistance between V 2 O 5 cathode materials and conductive agents (molten salt and super carbon) is one of the biggest issues that hinder the development of high specific energy thermal batteries. Designing fast Li+ and e– transport channels in cathode electrodes is considered as an effect method to improve electrochemical performance. Hence, a high-temperature ultrafast welding is proposed to reduce V 2 O 5 /conductive agents interfacial resistance by reconstructing the transmission channels of Li+ and e– in this paper. The experimental studies reveal the optimum ultrafast welding of 700 °C for 10 s, eliminating gap resistance of cathode electrodes induced by the melt of solid molten salt and rebuilding the more plentiful Li+ and e– transport channels, further reducing the contact resistance and gap resistance. Therefore, the electrodes deliver a high specific capacity of 270.69 mAh g−1 and a high specific energy of 610.60 Wh kg−1 at 0.1 A cm−2 and 500 °C with a cut-off voltage of 1.6 V. The high-temperature ultrafast welding provides guidance to build Li+ and e– transport channels of other cathode materials in thermal batteries. [ABSTRACT FROM AUTHOR]

The policy decision of extending electric power transmission lines to connect a remote area to a primary grid vs. developing local electricity generation resources must be informed by studies considering both alternatives' economic and environmental outcomes. Such analysis must also consider the uncertainty of several factors such as fuel prices, the cost and performance of renewable and conventional power generation technologies, and the value of environmental benefits. This paper presents a method for this analysis, making two main contributions to the literature. First, it shows how to characterize the two alternatives (i.e., main-grid extension vs. local power generation) in detail for precise quantification of their capital and operating costs while guaranteeing that they are both adequate to meet forecast demand and operating reserves. Second, it shows how to properly account for the economic and environmental implications of renewable energy intermittency and uncertainty through the optimization of capital investments and hourly operations. The method is illustrated by applying this analysis method to Saudi Arabia, where the government is struggling to outline a strategy to meet residential and commercial loads reliably and sustainably in the country's remote, scattered, isolated areas. To meet this demand, the Saudi government is considering two main alternatives: (1) extending the primary power transmission grid; or (2) installing an optimal combination of off-grid distributed generation (DG) resources, including solar PV, wind, diesel, oil, heavy fuel oil, and Li-ion batteries, to generate the electricity locally. Results suggest that under most scenarios of capital costs, fuel prices, and costs of air pollution, developing a microgrid with a large share of wind and solar power is more cost-effective than extending a primary grid 150 km or more away. Extending a primary grid powered by gas-fired combined-cycle power plants is more economical only if the load is not very high, the distance is not more than 350 km, and oil prices are relatively high compared to natural gas. [ABSTRACT FROM AUTHOR]

Smart and mechanically flexible energy harvesting/storage devices are attractive for the immensely growing electronic, automobile, medical, and aerospace markets. The leading challenges with current devices are their limitations regarding installation on curvy design, high-manufacturing cost, and lower production rate. Therefore, new design strategies in terms of new materials, cost, and ability to scale up fabrication are imperative to meet the contemporary and future demands of these fast-growing markets. Flexographic printing is one of the newest technologies that promises cost-effective energy devices with better energy harvesting and high storage performance. Current knowledge, selection of suitable materials, and methods of flexographic printing for solar cell and battery construction are reviewed and summarized in this paper in comparison to existing printing technologies. The main purpose of this review is to provide a comprehensive idea of flexographic printing for energy devices. [ABSTRACT FROM AUTHOR]

The main objective of this paper is, based on the theory of complex systems (Arthur, 2009), to reconstruct the inventive activity of lead-acid batteries used in electric vehicles. Based on the information from the United States Patent and Trademark Office (USPTO) database, and based on the methodology developed by Strumsky and Lobo (2015), it is possible to represent different degrees of inventive novelty (origination, new combination, recombination and reuse), as well as measuring the increasing technological complexity of lead-acid batteries. Evidence shows that the lead-acid battery is an increasingly complex technology. It is a rival technology but is also complementary to the nickel-metal-hydride and lithium-ion batteries used by electric and hybrid vehicles. [ABSTRACT FROM AUTHOR]