Applications In Energy Storage Systems Research Articles

Synthesis and characterization of BxPU-Liy: A novel polyurethane-based solid electrolyte with disrupted crystallinity for enhanced ion transport

In response to the demand for high-performance and safe batteries in the field of energy storage, a novel polyurethane-based solid electrolyte system, BxPU-Liy, has been developed. Crystallinity had been effectively reduced by incorporating 1,1′-binaphthol with a special molecular structure leading enhanced ion migration. Among that, B5PU-Li20 demonstrates good mechanical properties and thermal stability, with an ionic conductivity of 3.28 × 10-5 S cm−1 at room temperature, increasing to 2.0 × 10-4 S cm−1 at 40 °C. Additionally, this material exhibits excellent electrochemical performance and battery cycling capabilities, offering a new direction for the development of high-performance battery technology, with potential applications in portable electronic devices, electric vehicles, and large-scale energy storage systems.

IMPROVING ENERGY CONVERSION USING MXENES: EFFICIENCY ANALYSIS

Maximizing energy conversion efficiency is a major goal in the field of sustainable energy systems. In recent years, MXenes, a new class of two-dimensional materials, have attracted much attention in the context of improving energy conversion efficiency. This literature review provides an overview of the current state of energy research on MXenes, including their synthesis, characterization, and applications in energy storage and conversion systems. There are various methods for the synthesis of MXenes that are being developed to obtain materials with optimal structural and electrochemical properties. Characterization studies of MXenes examine their electrochemical properties, structure, surface, and physicochemical behavior to understand the underlying energy conversion mechanisms and optimize their performance. Applications of MXenes in energy storage and conversion systems include their use in solar cells, thermoelectric devices and batteries. MXenes have high conductivity, mechanical strength, and chemical stability, making them attractive for these applications. Continued research is needed to more fully understand the physical and chemical properties of MXenes and to develop optimal synthesis and application methods to achieve maximum energy conversion efficiency.

Nanosheet‐like MoO3 and conductive PANI electrodeposited on flexible carbon cloth for self‐supported solid‐state supercapacitor electrode

AbstractIn this paper, uniformly transition metal oxide (MoO3) nanosheets were electrochemically deposited on flexible carbon cloth (CC), and then conductive polyaniline (PANI) was orderly wrapped around their surface by electrochemical polymerization. The morphology and structure of as‐obtained self‐supported PANI/MoO3/CC electrode were investigated by FTIR, X‐ray diffraction, Raman, scanning electron microscope (SEM), transmission electron microscopy (TEM), and X‐ray photoelectron spectroscopy measurements in detail. Among all PANI/MoO3/CC electrode, the self‐supported PMC‐3 (deposition time of 300 s) has high specific capacitance of 841.6 F g−1 at current density of 0.5 A g−1 in the three‐electrode system, having specific capacitance of 595.7 F g−1 even at 10 A g−1. Novelty, the as‐assembled symmetrical capacitor is flexible and convenient with power density of 199.93 W kg−1 at the energy density of 9.69 Wh kg−1 and the energy density of 3.88 Wh kg−1 at power density of 4000 W kg−1. Thus, the electrochemical properties of the self‐supported PANI/MoO3/CC electrode were significantly improved, and the self‐supported electrodes are more competitive than other materials in practical application of clean energy storage systems.

(Digital Presentation) Hybrid Membranes Engineered from Sustainable Sources Exhibit Improved Ionic Conductivity

Ion-conducting membranes are crucial in electrochemical storage and energy conversion technologies such as fuel cells, alkaline ion batteries, and redox-flow batteries. The purpose of the membrane is to prevent direct contact between the electrodes while allowing selective ions to pass through. The characteristics of the ion-conducting membranes include excellent mechanical and thermal stability, chemical resistance, high ionic conductivity, and selectivity. Polymers and polymer-based precursors make up the majority of the materials that have been used as ion-conducting membranes. However, most polymer-based membranes have issues related to poor chemical resistance, recyclability, and thermal and mechanical stability. In addition, as more sustainable materials are being sought to create a sustainable society, new environmentally friendly and economically viable materials are in high demand. The clay-based material could be an alternative for ion-conducting applications due to its porous structure, high surface area, tunable interlayer spacing, excellent thermal and mechanical stability, and high ion conductivity. Clay minerals are primarily used in water treatment, pharmaceutics, ceramics, paints, and coating industries. Furthermore, clay minerals have been used as a filler material in energy storage and conversion system to improve the thermal stability and ion conductivity in electrodes, electrolytes, and separators.Herein, we report a novel approach to making non-polymeric hybrid clay membranes using environmentally benign materials such as clay and zwitterion (i.e., sulfobetaine). These membranes with improved ionic conductivity will find immense potential in applications in energy storage and conversion systems. Such membranes have been synthesized by intercalating sulfobetaine molecules into the interlayer spacing of the bentonite clay matrix. Sulfobetaine is a zwitterion composed of quaternary ammonium cations and sulfonate anions. Leveraging the unique structure-property features that exist in zwitterions helps to alter the interlayer spacings in the clay matrix, thereby enabling ion diffusion through the silicate layers. Furthermore, it helps in the formation of a self-supporting membrane. The functionalized membrane's crystal structure and chemical composition were investigated using XRD, XPS, and ATR-FTIR. XRD was used to identify the layered structure of the silicates in clay and the increased interlayer spacing (1.15 nm to 1.8 nm) of the hybrid clay membrane. Data from XPS and ATR-FTIR confirmed the successful functionalization of clay with sulfobetaine. Furthermore, the ionic conductivity of the hybrid clay membrane was characterized using a non-aqueous lithium electrolyte solution, and found a conductivity of . This is one of the first reports showcasing how zwitterions can impart conductivity in clay silicate motifs. It suggests an easy and novel approach to transport lithium-ion through silicate layers, thereby making it suitable for use as membranes in batteries and supercapacitors. The current study demonstrates an easy and versatile approach to developing cost-effective and eco-friendly membranes from sustainable materials such as clay, which, when functionalized, has the potential to be a highly efficient ion-conducting material with applications in energy storage, devices, and technologies.

Borate-Coated Co-Free LiNi0.5Mn1.5O4: Enhanced Performance and Stability for High-Power-Density Libs

Cobalt free LiNi0.5Mn1.5O4 (LNMO), also known as high-voltage spinel, has emerged as a promising cathode material for high energy-density and high power-density lithium-ion batteries (LIBs), making it a viable candidate for applications in large-scale energy storage systems (ESS) and transportation (1-5). Despite its potential, LNMO faces challenges, such as rapid capacity degradation and the formation of an unstable cathode electrolyte interphase (CEI), which have impeded its commercialization(4-5). To address these issues, we present a cost-effective and scalable approach involving the application of a borate-based surface coating to LNMO (borate-LNMO). In this study, we systematically applied varying amounts of borate coating to LNMO and assessed their electrochemical performance in both half- and full-cell configurations. Initial optimization of the coating amount revealed that borate-LNMO materials exhibited superior rate capability, and enhanced stability when compared to bare LNMO. Float testing demonstrated a stable LNMO/electrolyte interface for borate-LNMO materials, in contrast to the continuous increase in leakage (parasitic current) observed with bare LNMO over time. Furthermore, borate-LNMO materials exhibited superior cycling performance in full-cell setups, both at ambient (25℃) and elevated (45℃) temperatures. This enhanced performance can be attributed to the formation of relatively stable CEI and SEI interphases, resulting in reduced electrolyte decomposition, lower transition metal dissolution at the LNMO/electrolyte interface, and minimized cross-talk between the cathode and anode. Post-mortem SEM analysis of the cycled graphite anodes revealed a thicker and denser SEI in bare LNMO cells, whereas borate-LNMO cells exhibited a thinner and porous SEI. These findings suggest that borate-coated LNMO could be a promising solution for cost-effective and high-power LIBs.

Metal(Pt, Pd)-Perovskite Oxide(Ba0.5Sr0.5Co0.8Fe0.2O3-δ) Hybrid Material As a Bifunctional Electrocatalyst for Lithium-Air Battery

The rapid depletion of fossil fuel resources and growing concerns over climate change have made the development of next-generation batteries a top priority. Among these, Li-O2 batteries have attracted significant interest due to their potential for much higher gravimetric energy storage density compared to other chemical batteries. However, efficient and cost-effective catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are critical for the efficient functioning of these batteries.In recent years, complex perovskite oxides, such as Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), have been identified as promising candidates for bifunctional catalysts due to their defective structures and excellent oxygen mobility. However, while BSCF exhibits high OER activity, its ORR performance is poor. To address this issue, researchers have turned to metal-oxide composite catalysts, where nanosized metals are deposited on the surface of perovskite oxides, to increase activity and stability towards ORR due to the synergistic effect between metal and oxide support.In this study, we report the development of bifunctional electrocatalysts with highly electrocatalytic activity for ORR and OER. We used a simple wet-chemical processing technique to deposit metal catalysts with superior ORR activity on perovskite oxide-based catalysts with high OER activity. The direct deposition method is an effective way to create a good distribution of metal catalysts, intimate contact between metal catalysts and BSCF perovskite oxide, which may contribute to the creation of a synergistic effect between them. Our results showed that the metal catalysts deposited on perovskite oxides of Pd@BSCF and Pt@BSCF exhibited better ORR activity than others and higher OER activity than the perovskite oxides alone, resulting in much-enhanced bifunctionality through a synergistic effect between the metal catalysts and perovskite oxides.We further investigated the enhanced bifunctional electrocatalytic activity of the metal catalysts deposited perovskite oxides for Li-O2 batteries. The assembled Li-O2 batteries with Pd@BSCF cathode demonstrated lower discharge/charge overpotential (0.8 V at the cutoff capacity of 500 mAh gcat -1) and improved cycling stability (over 70 cycles), indicating the effectiveness of our approach in enhancing the bifunctional activities of ORR and OER for application in electrochemical energy storage and conversion systems. The encouraging results obtained from this study might have been attributed to two mechanisms, namely, the synergistic effect of electronic transfer and RDS/spillover. Our study suggests that the deposition of metal catalysts on the surface of perovskite oxides (Pd@BSCF and Pt@BSCF) is an effective approach to enhance bifunctional activities of ORR and OER, making it a promising strategy for the development of next-generation batteries. Figure 1

Probing the Structure Evolution of Na-Cu-Mn-O Based Layered Oxide Cathode Materials in Sodium Ion Batteries

Sodium-ion batteries (SIBs) are considered as potential energy storage devices for large-scale energy storage system and smart power grids applications because of the low cost and abundant distribution of sodium in the earth's crust and ocean [1]. The development of highly efficient cathode materials for superior sodium storage is crucial for the development of SIBs. Among all the cathode materials, sodium transition-metal layered oxides, especially P2 and O3-typed layered oxides are of more interest due to their high theoretical capacity and easy synthesis [2,3]. From a structural point of view, P2 phase has an open pathway from one prismatic site to adjacent sites for more facile Na ion diffusion than O3 homologue. Therefore, the P2 phase shows not only better kinetic properties but improved cyclic stability thanks to its high structural stability.However, the pristine Na2/3MnO2 in P2 phase usually suffer from poor reversibility and dramatic capacity and voltage decay upon cycling, which origins form below issues: 1) the Na+/vacancy order-disorder transition, 2) the phase transition at high charge voltages due to MnO6 layers gliding 3) the Jahn-Teller distortion derived from Mn4+/Mn3+ redox couple, 4) the migration and dissolution of transition metals.[4] Up to now, a variety of improvement methods (doping and coating) have been utilized to stimulate the application of P2-type Na2/3MnO2 material. In particular, copper, as a low cost and environmental friendliness element, has also been introduced to synthesize multiple layered transition metal materials, like Na0.68Cu0.34Mn0.66O2, Na0.68Cu0.34Mn0.50Ti0.16O2, Na2/3Mn0.72Cu0.22Mg0.06O2 and so on. Furthermore, various redox behavior and structural evolution have also been explored. However, the process of structural transition during calcinating at different temperatures have been ignored, which leads to the unexpected neglect of some unique features of metastable phases in sintering materials.In our current work, Na2/3Cu1/3Mn2/3O2 in various phases have been successfully synthesized by sol-gel method and subsequently calcinated at different temperatures. XRD results show that Na2/3Cu1/3Mn2/3O2 calcinated at 600 °C (NCMO-600) is the triclinic phase, with the increasing calcination temperatures, the Na2/3Cu1/3Mn2/3O2 subsequently transfers to the hexagonal phase at 800 °C (NCMO-800). Subsequent electrochemical measurements show that NCMO-800 exhibit the better cycle stability and almost no voltage decay in the long term cycling, while the NCMO-600 sample exhibited rapid voltage attenuation at about 30 cycles. Besides, in situ XRD patterns and XANES spectra for both cathodes indicate slight different structural transition and electronic structure changes during charge and discharge. In a word, the NCMO-600 material exhibit the larger electron transfer at low current densities while the NCMO-800 material show the better cycle stability and rate performance.

The Distance Between Phosphate-Based Polyanionic Compounds and Their Practical Application For Sodium-Ion Batteries.

Sodium-ion batteries (SIBs) are a viable alternative to meet the requirements of future large-scale energy storage systems due to the uniform distribution and abundant sodium resources. Among the various cathode materials for SIBs, phosphate-based polyanionic compounds exhibit excellent sodium-storage properties, such as high operation voltage, remarkable structural stability, and superior safety. However, their undesirable electronic conductivities and specific capacities limit their application in large-scale energy storage systems. Herein, the development history and recent progress of phosphate-based polyanionic cathodes are first overviewed. Subsequently, the effective modification strategies of phosphate-based polyanionic cathodes are summarized toward high-performance SIBs, including surface coating, morphological control, ion doping, and electrolyte optimization. Besides, the electrochemical performance, cost, and industrialization analysis of phosphate-based polyanionic cathodes for SIBs are discussed for accelerating commercialization development. Finally, the future directions of phosphate-based polyanionic cathodes are comprehensively concluded. It is believed that this review can provide instructive insight into developing practical phosphate-based polyanionic cathodes for SIBs.

A review of vertical graphene and its energy storage system applications.

The pursuit of advanced materials to meet the escalating demands of energy storage system has led to the emergence of vertical graphene (VG) as a highly promising candidate. With its remarkable strength, stability, and conductivity, VG has gained significant attention for its potential to revolutionize energy storage technologies. This comprehensive review delves deeply into the synthesis methods, structural modifications, and multifaceted applications of VG in the context of lithium-ion batteries, silicon-based lithium batteries, lithium-sulfur batteries, sodium-ion batteries, potassium-ion batteries, aqueous zinc batteries, and supercapacitors. The review elucidates the intricate growth process of VG and underscores the paramount importance of optimizing process parameters to tailor VG for specific applications. Subsequently, the pivotal role of VG in enhancing the performance of various energy storage and conversion systems is exhaustively discussed. Moreover, it delves into structural improvement, performance tuning, and mechanism analysis of VG composite materials in diverse energy storage systems. In summary, this review provides a comprehensive look at VG synthesis, modification, and its wide range of applications in energy storage. It emphasizes the potential of VG in addressing critical challenges and advancing sustainable, high-performance energy storage devices, providing valuable guidance for the development of future technologies.

High-Performance Supercapacitors Using Hierarchical And Sulfur-Doped Trimetallic NiCo/NiMn Layered Double Hydroxides.

A supercapacitor features high power density and long cycling life. However, its energy density is low. To ensemble a supercapacitor with high power- and energy-densities, the applied capacitor electrodes play the key roles. Herein, a high-performance capacitive electrode is designed and grown on a flexible carbon cloth (CC) substrate via a hydrothermal reaction and a subsequent ion exchange sulfuration process. It has a 3D heterostructure, consisting of sulfur-doped NiMn-layered double hydroxide (LDH) nanosheets (NMLS) and sulfur-doped NiCo-LDH nanowires (NCLS). The electrode with sheet-shaped NMLS and wire-shaped NCLS on their top (NMLS@NCLS/CC) increases the available surface area, providing more pseudocapacitive sites. It exhibits a gravimetric capacity of 555.2 C g-1 at a current density of 1 A g-1 , the retention rate of 75.1% when the current density reaches up to 20 A g-1 , as well as superior cyclic stability. The assembled asymmetric supercapacitor that is composed of a NMLS@NCLS/CC positive electrode and a sulfurized activated carbon negative electrode presents a maximum energy density of 24.2Wh kg-1 and a maximum power density of 16000W kg-1 . In this study, a facile strategy for designing hierarchical LDH materials is demonstrated as well as their applications in advanced energy storage systems.

Multi time scale management and coordination strategy for stationary super capacitor energy storage in urban rail transit power supply system

The application of stationary super capacitor energy storage systems (SCESS) is an effective way to recover the regenerative braking energy of urban rail transit vehicles. The benefits of these systems’ application largely depend on the design of the energy management strategy (EMS). In this paper, the EMS core demand of SCESS is analyzed and divided into different levels based on the considered time scale. On this basis, control objectives and mathematical models were analyzed considering different time scales. Then, an EMS based on a genetic and fuzzy algorithm was presented. The feasibility and effectiveness of the proposed EMS were verified through the simulation of actual line parameters. The results indicated that the EMS can satisfy the control requirements of multiple time scales of SCESS. It is capable of effectively achieving energy management and coordinated control of multiple SCESS. As a result, it also for energy savings in the urban rail transit power supply system.

The effect of electric vehicle charging demand variability on optimal hybrid power systems with second-life lithium-ion or fresh Na–S batteries considering power quality

Second-life batteries (SLB) in energy storage systems (ESS) can provide an economical solution to hybrid power systems (HPS) by reducing environmental concerns in battery production. Could Na–S batteries be a suitable alternative for ESS applications if the toxicity problem can be solved? This article performs the optimal sizing and feasibility analysis of an electric vehicle charging station with a minimum cost objective under daily, hourly, and hybrid demand variability with multi-year sensitivity analyses for both ESS technologies. Moreover, the scope is deepened with sensitivity analyses based on solar horizontal irradiation, wind speed, and electricity selling prices. Due to the HPS connection to the distribution busbar, power quality issues are included in the cost-based optimization framework, and the effects of power quality issues on the sizing and feasibility outputs are compared at higher demand variability. The results show that using SLB at wind speeds lower than 4.7 m/s and irradiances lower than 3 kWh/m2/day or above 0.035 $/kWh electric sale price is not economical. Grid-connected HPSs can increase current and voltage harmonics at the distribution busbar by up to 55.3 % and 4.3 %, reduce the power factor by up to 46.8 %, and extend the payback period by up to 1 year.

Enhancing pseudocapacitive energy storage system performance with electrodeposited CuSx and CoSx biphasic transitional metal sulfide (TMS) based nanostructured electrode on nickel foam

This study investigated the pseudocapacitive energy storage system of biphasic CuSx and CoSx electrodeposited on nickel foam (NF). XRD, FESEM, and EDX show the formation of nano-flower-shaped biphasic layer on NF. The biphasic electrode shows higher areal specific capacitance (Csp) than the single-layered NF/CuSx and NF/CoSx electrodes. The Csp of the NF/CuSx/CoSx drops by 42 % as the scan rate (ϑ) rises from 5 mV s−1 to 20 mV s−1. Electrode polarization and reduced ion migration occurring with rapid scan rates are responsible for this decrement. Galvanostatic charge-discharge (GCD) analysis showed that Csp declined from 11.42 to 9.63 F cm−2, and the retained Csp was 84 % as the current density shifted from 4 to 8 mA cm−2. The energy density of 0.30 mWh.cm−2 and power density of 1.57 mW cm−2 imply significant energy storage capability of the electrode. The kinetic analysis indicates that 78 % of the capacitance is diffusion-controlled process in the NF/CuSx/CoSx electrode. The b-value of around 0.7 suggests that the pseudocapacitance mostly originates from diffusion-controlled processes. The poor cyclic stability of NF/CuSx/CoSx was demonstrated by only upholding 61 % of its original Csp after 500 cycles. However, the higher coulombic efficiency indicates that a greater proportion of the electrical charge is stored in the supercapacitor. The study explores the biphasic design of copper and cobalt sulphide-based electrodes as potential pseudocapacitive energy storage system applications such as supercapacitors and supercapatteries.

Design and investigation of cold storage material for large-scale application in supercritical compressed air energy storage system

The compressed air energy storage is widely studied as promising large-scale energy storage technology. This study focus on the design and investigation of cold storage material for large-scale application in supercritical compressed air energy storage system. Different kinds of cold storage materials for supercritical compressed air energy storage system are comparatively analyzed at first, and the sodium chloride is selected as the suitable cold storage material for supercritical compressed air energy storage system. Meanwhile, the thermal and mechanical properties of suitable sodium chloride particle are measured. The results show that the density of sodium chloride particle is 2.1589 g/cm3. The average specific heat and thermal conductivity of sodium chloride particle are 0.81 J/(g·K) and 5.8576 W/(m·K) in the test temperature range. In addition, the average values of Mohs hardness and Vickers hardness of processed sodium chloride particles are 3 Mohs and 11.7 HV, respectively. The maximum compressive strength of sodium chloride samples tested at −196 °C and 20 °C are 6.25 MPa and 24.45 MPa, respectively. Furthermore, the abradability of sodium chloride particles are tested, the mass loss rate of sodium chloride particles is 0.11 %. The cold storage performance of the designed and processed sodium chloride particle cold storage materials is numerically simulated. The average temperature of sodium chloride particles gradually decreases from 293.15 K to 119.26 K, which can storage 37,128.57 kJ cold energy in total. This work can provide basic data for the further cold storage material research of supercritical compressed air energy storage system.

Hierarchically Porous Carbon Networks Derived from Chitosan for High-Performance Electrochemical Double-Layer Capacitors.

Activated carbon (AC) compounds derived from biomass precursors have garnered significant attention as electrode materials in electric double-layer capacitors (EDLCs) due to their ready availability, cost-effectiveness, and potential for mass production. However, the accessibility of their active sites in electrochemistry has not been investigated in detail. In this study, we synthesized two novel macro/micro-porous carbon structures prepared from a chitosan precursor using an acid/potassium hydroxide activation process and then examined the relationship between their textural characteristics and capacitance as EDLCs. The material characterizations showed that the ACs, prepared through different activation processes, differed in porosity, with distinctive variations in particle shape. The sample activated at 800 °C (Act-chitosan) was characterized by plate-shaped particles, a specific surface area of 4128 m2/g, and a pore volume of 1.87 cm3/g. Assessment of the electrochemical characteristics of Act-chitosan showed its remarkable capacitance of 183.5 F/g at a scan rate of 5 mV/s, and it maintained exceptional cyclic stability even after 10,000 cycles. The improved electrochemical performance of both chitosan-derived carbon structures could thus be attributed to their large, well-developed active sites within pores < 2 nm, despite the fact that interconnected macro-porous particles can enhance ion accessibility on electrodes. Our findings provide a basis for the fabrication of biomass-based materials with promising applications in electrochemical energy storage systems.

Strategic Guidelines for Battery Energy Storage System Deployment: Regulatory Framework, Incentives, and Market Planning

This research addresses strategic recommendations regarding the applications of battery energy storage systems (BESS) in the context of the deregulated electricity market. The main emphasis is on regulatory dimensions, incentive mechanisms, and the provision of marketable storage services. The study’s findings demonstrate that battery energy storage systems (BESS) have distinct characteristics that challenge their conventional classification as a load or generator within power systems. The study additionally emphasizes the insights, lessons learned, and good practices gained from early adopter countries in implementing energy storage systems (ESS). These insights include the importance of establishing a precise definition of ESS, promoting collaborative engagement with relevant stakeholders, and developing a series of incentive strategies. The results show that nations that pioneered BESS’s application in their electricity matrices have effectively promoted storage services in deregulated markets, employing storage assets for various purposes such as peak reduction, frequency regulation, renewable energy support, and energy arbitrage applications. These applications underline the potential of BESS to increase grid stability and minimize exposure to risk and volatility in the revenues of storage agents in deregulated markets.

Influence of carbon graphene flakes enriched PCM on partial charging conditions for cool thermal energy storage system applications

The present research work is aimed at studying the influence of carbon graphene flakes nanoparticle concentrations in DI water at various heat transfer fluid temperatures of −6, −9, and −12 °C. The carbon graphene flakes (CGF) with higher concentrations of 0.4, 0.8, and 1.2% with the base PCM is investigated experimentally in a stainless steel spherical capsule of 100 mm diameter, and the thermophysical properties of the CGF PCMs were interpreted with the charging behaviours of the base PCM. The CGF PCMs help to reduce the solidification time by 47 to 56% for the higher bath temperature of −6 °C in partial charging conditions. For the complete solidification, the maximum reduction in solidification time was attained between 14 and 21% for the CGF PCM with a concentration of 1.2%. The partial charging conditions favour the increase in heat flux two-fold when the bath temperature is operated at −6 °C, this reduces the demand for energy during the peak hours and shifts the peak load conditions. It is concluded that the CGF PCMs with a concentration of 1.2% help in enhancing the heat transfer rate and significantly compress the solidification duration compared to the bath temperatures of −9 °C and −12 °C.

Characterization and energy storage performance assessment of repurposed 18650 cylindrical lithium-ion cells for second life application in battery energy storage systems

Characterization and energy storage performance assessment of repurposed 18650 cylindrical lithium-ion cells for second life application in battery energy storage systems

An ultimate peak load shaving control algorithm for optimal use of energy storage systems

Peak load shaving is one of the applications of energy storage systems (ESS) that will play a key role in the future of smart grid. Peak shaving is done to prevent the increase of network capacity to the amount of peak demand and also increase its reliability. Although the development of diverse ESS with high round-trip efficiency is very important and is considered a necessary condition for optimal peak load shaving, its sufficient condition is to follow an appropriate control algorithm. In this study, a new control algorithm called ultimate peak load shaving (UPLS) is developed for the optimal use of ESS for the peak shaving and valley filling purposes. The UPLS control algorithm is not only able to guarantee peak load shaving in any condition considering any load profile but also can ingeniously control ESS charging and discharging rates. This feature distinguishes it from other algorithms developed in the field.In this study, first, the UPLS control algorithm was explained in detail. Then, by comparing it with two other common control algorithms, its four unique features were investigated. After that, by applying these three control algorithms on different hypothetical load demand profiles A, B, C, and D, these features were demonstrated. Through sensitivity analysis and changing the allowed range for ESS charging and discharging rates (other parameters are assumed constant), how to design the grid power, Pg(t) by the UPLS control algorithm is described. It was found that the mentioned parameters are completely under the control of this algorithm. The optimization results show that peak demand can be reduced by 28.12 % and 27.82 % for load profiles B and C, respectively and the ESS discharging rate is significantly reduced to 55.28 % and 77.93 %, respectively compared to their corresponding values in basic design.

Research on design strategies and sensing applications of energy storage system based on renewable methanol fuel

The rapid depletion of traditional non-renewable fossil fuels has increased energy sustainability threats. Methanol is recognized as one of the viable alternatives to conventional fossil fuels mainly due to its high energy density and abundant raw materials. Direct methanol fuel cells (DMFCs) can convert the chemical energy of methanol into electricity in real time, which is one of the most effective ways to utilize methanol energy. However, DMFCs have undesirable performance, such as low fuel utilization, low cell voltage, and unstable output voltage, hindering the development of methanol energy technology. Herein, we design an energy storage system with high methanol energy efficiency based on passive micro DMFCs. This system with low power consumption (only uW scale) can extract the high chemical energy in methanol, efficiently convert it into electric energy, and store it to output a stable voltage for load. Moreover, application research on this system has been carried out. A self-powered methanol concentration sensor is designed and implemented on a printed circuit board. It can detect methanol solution with a concentration of 3 M–12 M, only requiring it to be tested as fuel without an additional power supply. The sensor has about 1.1 mW total power consumption and 0.34 s response time. This study on the energy conversion and storage of sustainable methanol fuel aims to provide a reference to explore the application of renewable energy.