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Progress in renewable energy production has directed interest in advanced developments of energy storage systems. The all-vanadium redox flow battery (VRFB) is one of the attractive technologies for large scale energy storage due to its design versatility and scalability, longevity, good round-trip efficiencies, stable capacity and safety. Despite these advantages, the deployment of the vanadium battery has been limited due to vanadium and cell material costs, as well as supply issues. Improving stack power density can lower the cost per kW power output and therefore, intensive research and development is currently ongoing to improve cell performance by increasing electrode activity, reducing cell resistance, improving membrane selectivity and ionic conductivity, etc. In order to evaluate the cell performance arising from this intensive R&D, numerous physical, electrochemical and chemical techniques are employed, which are mostly carried out ex situ, particularly on cell characterizations. However, this approach is unable to provide in-depth insights into the changes within the cell during operation. Therefore, in situ diagnostic tools have been developed to acquire information relating to the design, operating parameters and cell materials during VRFB operation. This paper reviews in situ diagnostic tools used to realize an in-depth insight into the VRFBs. A systematic review of the previous research in the field is presented with the advantages and limitations of each technique being discussed, along with the recommendations to guide researchers to identify the most appropriate technique for specific investigations.
Purna Ghimire; Arjun Bhattarai; Tuti Lim; Nyunt Wai; Maria Skyllas-Kazacos; Qingyu Yan. In-Situ Tools Used in Vanadium Redox Flow Battery Research—Review. Batteries 2021, 7, 53 .
AMA StylePurna Ghimire, Arjun Bhattarai, Tuti Lim, Nyunt Wai, Maria Skyllas-Kazacos, Qingyu Yan. In-Situ Tools Used in Vanadium Redox Flow Battery Research—Review. Batteries. 2021; 7 (3):53.
Chicago/Turabian StylePurna Ghimire; Arjun Bhattarai; Tuti Lim; Nyunt Wai; Maria Skyllas-Kazacos; Qingyu Yan. 2021. "In-Situ Tools Used in Vanadium Redox Flow Battery Research—Review." Batteries 7, no. 3: 53.
A model based approach is developed to determine the membrane permeability properties including vanadium ion crossover and water transfer behaviour for the vanadium redox flow battery (VRB) system. The permeability of vanadium ions and water transfer coefficients are estimated through nonlinear optimisation with measured negative and positive half-cell potentials. Experimental studies were conducted to test two different membranes as examples to illustrate the effectiveness of the proposed approach. This method can significantly simplify the conventional approach to characterising the membrane permeability property. The results are useful for online prediction of the battery system capacity decay and for scheduling regular maintenance such as electrolyte rebalancing to restore capacity.
Yifeng Li; Longgang Sun; Liuyue Cao; Jie Bao; Maria Skyllas-Kazacos. Dynamic model based membrane permeability estimation for online SOC imbalances monitoring of vanadium redox flow batteries. Journal of Energy Storage 2021, 39, 102688 .
AMA StyleYifeng Li, Longgang Sun, Liuyue Cao, Jie Bao, Maria Skyllas-Kazacos. Dynamic model based membrane permeability estimation for online SOC imbalances monitoring of vanadium redox flow batteries. Journal of Energy Storage. 2021; 39 ():102688.
Chicago/Turabian StyleYifeng Li; Longgang Sun; Liuyue Cao; Jie Bao; Maria Skyllas-Kazacos. 2021. "Dynamic model based membrane permeability estimation for online SOC imbalances monitoring of vanadium redox flow batteries." Journal of Energy Storage 39, no. : 102688.
After 35 years of research and development that began at UNSW Sydney in 1985, the All-Vanadium Redox Flow Battery is now being commercialized by a number of companies around the world in applications such as load levelling, peak shaving and renewable energy storage. It is unique amongst all flow battery chemistries in that it uses the same element in both half-cells, thereby eliminating problems of cross contamination and providing indefinite life for the electrolyte. This article presents a detailed overview of the VRFB technology, beginning with the original research and development at UNSW, through to the more recent improvements in cell materials and design that have enhanced power density and reduced costs. Early field testing and current commercialization activities are also described.
Maria Skyllas-Kazacos; Chris Menictas. Vanadium Redox Flow Batteries. Reference Module in Earth Systems and Environmental Sciences 2021, 1 .
AMA StyleMaria Skyllas-Kazacos, Chris Menictas. Vanadium Redox Flow Batteries. Reference Module in Earth Systems and Environmental Sciences. 2021; ():1.
Chicago/Turabian StyleMaria Skyllas-Kazacos; Chris Menictas. 2021. "Vanadium Redox Flow Batteries." Reference Module in Earth Systems and Environmental Sciences , no. : 1.
A vanadium oxygen fuel cell is a modified form of a conventional vanadium redox flow battery (VRFB) where the positive electrolyte (VO2+/VO2+ couple) is replaced by the oxygen reduction (ORR) process. This potentially allows for a significant improvement in energy density and has the added benefit of overcoming the solubility limits of V (V) at elevated temperatures, while also allowing the vanadium negative electrolyte concentration to increase above 3 M. In this paper, a vanadium oxygen fuel cell with vanadium electrolytes with a concentration of up to 3.6 M is reported with preliminary results presented for different electrodes over a range of current densities. Using precipitation inhibitors, the concentration of vanadium can be increased considerably above the commonly used 2 M limit, leading to improved energy density.
Mandar Risbud; Chris Menictas; Maria Skyllas-Kazacos; Jens Noack. Vanadium Oxygen Fuel Cell Utilising High Concentration Electrolyte. Batteries 2019, 5, 24 .
AMA StyleMandar Risbud, Chris Menictas, Maria Skyllas-Kazacos, Jens Noack. Vanadium Oxygen Fuel Cell Utilising High Concentration Electrolyte. Batteries. 2019; 5 (1):24.
Chicago/Turabian StyleMandar Risbud; Chris Menictas; Maria Skyllas-Kazacos; Jens Noack. 2019. "Vanadium Oxygen Fuel Cell Utilising High Concentration Electrolyte." Batteries 5, no. 1: 24.
The battery energy storage system has become an indispensable part of the current electricity network due to the vast integration of renewable energy sources (RESs). This paper proposes an optimal charging method of a vanadium redox flow battery (VRB)-based energy storage system, which ensures the maximum harvesting of the free energy from RESs by maintaining safe operations of the battery. The VRB has a deep discharging capability, long cycle life, and high energy efficiency with no issues of cell-balancing, which make it suitable for large-scale energy storage systems. The proposed approach determines the appropriate charging current and the optimal electrolyte flow rate based on the available time-varying input power. Moreover, the charging current is bounded by the limiting current, which prevents the gassing side-reactions and protects the VRB from overcharging. The proposed optimal charging method is investigated by simulation studies using MATLAB/Simulink.
Parvez Akter; Yifeng Li; Jie Bao; Maria Skyllas-Kazacos; Muhammed Fazlur Rahman. Optimal Charging of Vanadium Redox Flow Battery with Time-Varying Input Power. Batteries 2019, 5, 20 .
AMA StyleParvez Akter, Yifeng Li, Jie Bao, Maria Skyllas-Kazacos, Muhammed Fazlur Rahman. Optimal Charging of Vanadium Redox Flow Battery with Time-Varying Input Power. Batteries. 2019; 5 (1):20.
Chicago/Turabian StyleParvez Akter; Yifeng Li; Jie Bao; Maria Skyllas-Kazacos; Muhammed Fazlur Rahman. 2019. "Optimal Charging of Vanadium Redox Flow Battery with Time-Varying Input Power." Batteries 5, no. 1: 20.
In this study, 1.6 M vanadium electrolytes in the oxidation forms V(III) and V(V) were prepared from V(IV) in sulfuric (4.7 M total sulphate), V(IV) in hydrochloric (6.1 M total chloride) acids, as well as from 1:1 mol mixture of V(III) and V(IV) (denoted as V3.5+) in hydrochloric (7.6 M total chloride) acid. These electrolyte solutions were investigated in terms of performance in vanadium redox flow battery (VRFB). The half-wave potentials of the V(III)/V(II) and V(V)/V(IV) couples, determined by cyclic voltammetry, and the electronic spectra of V(III) and V(IV) electrolyte samples, are discussed to reveal the effect of electrolyte matrix on charge-discharge behavior of a 40 cm2 cell operated with 1.6 M V3.5+ electrolytes in sulfuric and hydrochloric acids. Provided that the total vanadium concentration and the conductivity of electrolytes are comparable for both acids, respective energy efficiencies of 77% and 72–75% were attained at a current density of 50 mA∙cm−2. All electrolytes in the oxidation state V(V) were examined for chemical stability at room temperature and +45 °C by titrimetric determination of the molar ratio V(V):V(IV) and total vanadium concentration.
Nataliya Roznyatovskaya; Jens Noack; Heiko Mild; Matthias Fühl; Peter Fischer; Karsten Pinkwart; Jens Tübke; Maria Skyllas-Kazacos. Vanadium Electrolyte for All-Vanadium Redox-Flow Batteries: The Effect of the Counter Ion. Batteries 2019, 5, 13 .
AMA StyleNataliya Roznyatovskaya, Jens Noack, Heiko Mild, Matthias Fühl, Peter Fischer, Karsten Pinkwart, Jens Tübke, Maria Skyllas-Kazacos. Vanadium Electrolyte for All-Vanadium Redox-Flow Batteries: The Effect of the Counter Ion. Batteries. 2019; 5 (1):13.
Chicago/Turabian StyleNataliya Roznyatovskaya; Jens Noack; Heiko Mild; Matthias Fühl; Peter Fischer; Karsten Pinkwart; Jens Tübke; Maria Skyllas-Kazacos. 2019. "Vanadium Electrolyte for All-Vanadium Redox-Flow Batteries: The Effect of the Counter Ion." Batteries 5, no. 1: 13.
Liuyue Cao; Maria Skyllas-Kazacos; Chris Menictas; Jens Noack. A review of electrolyte additives and impurities in vanadium redox flow batteries. Journal of Energy Chemistry 2018, 27, 1269 -1291.
AMA StyleLiuyue Cao, Maria Skyllas-Kazacos, Chris Menictas, Jens Noack. A review of electrolyte additives and impurities in vanadium redox flow batteries. Journal of Energy Chemistry. 2018; 27 (5):1269-1291.
Chicago/Turabian StyleLiuyue Cao; Maria Skyllas-Kazacos; Chris Menictas; Jens Noack. 2018. "A review of electrolyte additives and impurities in vanadium redox flow batteries." Journal of Energy Chemistry 27, no. 5: 1269-1291.
Through targeted and reproducible electrochemical treatment of glassy carbon electrodes, investigations have been carried out on the electrochemical behaviour of the oxidation of V2+, VO2+ and the reductions of VO2+, VO2+ and V3+ in order to pretreat electrodes specifically for use in vanadium redox flow batteries and, if possible, to treat them in situ. For this purpose, a glassy carbon electrode was treated potentiostatically for a period of 30 s at different potentials in the range of 500 mV–2000 mV vs. Hg/Hg2SO4 in 2 M H2SO4 and then linear sweep voltammograms were performed in the different vanadium-containing solutions. With this method, it could be shown that all reactions are extremely surface sensitive and the reaction speeds changed by several decades. The reaction rates increased significantly in all reactions compared to polished electrodes and had an optimum treatment potential of approx. 1600 mV vs. Hg/Hg2SO4, although the oxidation reaction of V2+ and the reduction reactions of V3+ and VO2+ had opposite tendencies to oxidation of VO2+ and the reduction of VO2+ in the area of low treatment potentials. In the former, the kinetics increased and in the latter, they decreased. In addition, causes were investigated using confocal microscopy and XPS. No correlation was found to the roughness or size of the stretched surfaces, although these changed significantly as a result of the treatment. XPS measurements gave indications of a dependence on hydroxyl groups for the oxidation of VO2+ and the reduction of VO2+, while for the reactions of oxygen-free cations and the reduction of VO2+ weak indications of a dependence on carboxyl groups were obtained.
Jens Noack; Nataliya Roznyatovskaya; Jessica Kunzendorf; Maria Skyllas-Kazacos; Chris Menictas; Jens Tübke. The influence of electrochemical treatment on electrode reactions for vanadium redox-flow batteries. Journal of Energy Chemistry 2018, 27, 1341 -1352.
AMA StyleJens Noack, Nataliya Roznyatovskaya, Jessica Kunzendorf, Maria Skyllas-Kazacos, Chris Menictas, Jens Tübke. The influence of electrochemical treatment on electrode reactions for vanadium redox-flow batteries. Journal of Energy Chemistry. 2018; 27 (5):1341-1352.
Chicago/Turabian StyleJens Noack; Nataliya Roznyatovskaya; Jessica Kunzendorf; Maria Skyllas-Kazacos; Chris Menictas; Jens Tübke. 2018. "The influence of electrochemical treatment on electrode reactions for vanadium redox-flow batteries." Journal of Energy Chemistry 27, no. 5: 1341-1352.
Yifeng Li; Xinan Zhang; Jie Bao; Maria Skyllas-Kazacos. Control of electrolyte flow rate for the vanadium redox flow battery by gain scheduling. Journal of Energy Storage 2017, 14, 125 -133.
AMA StyleYifeng Li, Xinan Zhang, Jie Bao, Maria Skyllas-Kazacos. Control of electrolyte flow rate for the vanadium redox flow battery by gain scheduling. Journal of Energy Storage. 2017; 14 ():125-133.
Chicago/Turabian StyleYifeng Li; Xinan Zhang; Jie Bao; Maria Skyllas-Kazacos. 2017. "Control of electrolyte flow rate for the vanadium redox flow battery by gain scheduling." Journal of Energy Storage 14, no. : 125-133.
Yifeng Li; Xinan Zhang; Jie Bao; Maria Skyllas-Kazacos. Studies on optimal charging conditions for vanadium redox flow batteries. Journal of Energy Storage 2017, 11, 191 -199.
AMA StyleYifeng Li, Xinan Zhang, Jie Bao, Maria Skyllas-Kazacos. Studies on optimal charging conditions for vanadium redox flow batteries. Journal of Energy Storage. 2017; 11 ():191-199.
Chicago/Turabian StyleYifeng Li; Xinan Zhang; Jie Bao; Maria Skyllas-Kazacos. 2017. "Studies on optimal charging conditions for vanadium redox flow batteries." Journal of Energy Storage 11, no. : 191-199.
Yitao Yan; Maria Skyllas-Kazacos; Jie Bao. Effects of battery design, environmental temperature and electrolyte flowrate on thermal behaviour of a vanadium redox flow battery in different applications. Journal of Energy Storage 2017, 11, 104 -118.
AMA StyleYitao Yan, Maria Skyllas-Kazacos, Jie Bao. Effects of battery design, environmental temperature and electrolyte flowrate on thermal behaviour of a vanadium redox flow battery in different applications. Journal of Energy Storage. 2017; 11 ():104-118.
Chicago/Turabian StyleYitao Yan; Maria Skyllas-Kazacos; Jie Bao. 2017. "Effects of battery design, environmental temperature and electrolyte flowrate on thermal behaviour of a vanadium redox flow battery in different applications." Journal of Energy Storage 11, no. : 104-118.
Molybdenum oxide MoO3 has been widely used in catalysts and electrochemical energy devices, but, to date, has not been investigated as an electrocatalyst in redox flow cells. In this study, MoO3 in the form of micro‐flakes was introduced onto carbon paper as an electrocatalyst and MoO42− as electrolyte additive for the vanadium redox couple reactions in the vanadium redox flow battery (VRFB). When the carbon paper was modified with MoO3 or MoO42− added to the electrolyte, the peak potential separations were measured as 171 and 203 mV for V2+/V3+ and 130 and 111 mV VO2+/VO2+ redox reactions, respectively, as compared with 306 and 144 mV for the bare pre‐treated carbon paper. A vanadium redox flow cell with MoO3‐CP electrodes exhibited a voltage efficiency of 85.4 % at 100 mA cm−2. The power density reached 200 mW cm−2 at a current density of 150 mA cm−2 when cycled within the voltage range of 0.6–1.7 V. These results indicate that MoO3‐based modification is a promising method for high power density VRFB applications.
Liuyue Cao; Maria Skyllas-Kazacos; Da-Wei Wang. Modification Based on MoO3 as Electrocatalysts for High Power Density Vanadium Redox Flow Batteries. ChemElectroChem 2017, 4, 1836 -1839.
AMA StyleLiuyue Cao, Maria Skyllas-Kazacos, Da-Wei Wang. Modification Based on MoO3 as Electrocatalysts for High Power Density Vanadium Redox Flow Batteries. ChemElectroChem. 2017; 4 (8):1836-1839.
Chicago/Turabian StyleLiuyue Cao; Maria Skyllas-Kazacos; Da-Wei Wang. 2017. "Modification Based on MoO3 as Electrocatalysts for High Power Density Vanadium Redox Flow Batteries." ChemElectroChem 4, no. 8: 1836-1839.
The inevitable diffusion of vanadium ions across the membrane can cause considerable capacity loss and temperature increase in vanadium redox flow batteries (VRFBs) over long term operation. Reliable experimental data of the permeability rates of vanadium ions are needed for membrane selection and for use in mathematical models to predict long-term behavior. In this paper a number of ion exchange membranes were selected for detailed evaluation using a modified approach to obtain more accurate permeation rates of V2+, V3+, VO2+ and VO2+ ions. Three commercial ion exchange membranes—FAP450, VB2 and F930—are investigated. The obtained diffusion coefficients are then employed in dynamic models to predict the thermal behavior under specific operating conditions. The simulation results prove that smaller and more balanced permeability rates of V2+ and VO2+ ions are more important to avoid large temperature increases in the cell stack during stand-by periods at high states-of-charge with pumps off.
Liuyue Cao; Anders Kronander; Ao Tang; Da-Wei Wang; Maria Skyllas-Kazacos. Membrane Permeability Rates of Vanadium Ions and Their Effects on Temperature Variation in Vanadium Redox Batteries. Energies 2016, 9, 1058 .
AMA StyleLiuyue Cao, Anders Kronander, Ao Tang, Da-Wei Wang, Maria Skyllas-Kazacos. Membrane Permeability Rates of Vanadium Ions and Their Effects on Temperature Variation in Vanadium Redox Batteries. Energies. 2016; 9 (12):1058.
Chicago/Turabian StyleLiuyue Cao; Anders Kronander; Ao Tang; Da-Wei Wang; Maria Skyllas-Kazacos. 2016. "Membrane Permeability Rates of Vanadium Ions and Their Effects on Temperature Variation in Vanadium Redox Batteries." Energies 9, no. 12: 1058.
The penetration of solar photovoltaic (PV) systems in residential areas contributes to the generation and usage of renewable energy. Despite its advantages, the PV system also creates problems caused by the intermittency of renewable energy. As suggested by researchers, such problems deteriorate the applicability of the PV system and have to be resolved by employing a battery energy storage system (BESS). With concern for the high investment cost, the choice of a cost-effective BESS with proper sizing is necessary. To this end, this paper proposes the employment of a vanadium redox flow battery (VRB), which possesses a long cycle life and high energy efficiency, for residential users with PV systems. It further proposes methods of computing the capital and maintenance cost of VRB systems and evaluating battery efficiency based on VRB electrochemical characteristics. Furthermore, by considering the cost and efficiency of VRB, the prevalent time-of-use electricity price, the solar feed-in tariff, the solar power profile and the user load pattern, an optimal sizing algorithm for VRB systems is proposed. Simulation studies are carried out to show the effectiveness of the proposed methods.
Xinan Zhang; Yifeng Li; Maria Skyllas-Kazacos; Jie Bao. Optimal Sizing of Vanadium Redox Flow Battery Systems for Residential Applications Based on Battery Electrochemical Characteristics. Energies 2016, 9, 857 .
AMA StyleXinan Zhang, Yifeng Li, Maria Skyllas-Kazacos, Jie Bao. Optimal Sizing of Vanadium Redox Flow Battery Systems for Residential Applications Based on Battery Electrochemical Characteristics. Energies. 2016; 9 (10):857.
Chicago/Turabian StyleXinan Zhang; Yifeng Li; Maria Skyllas-Kazacos; Jie Bao. 2016. "Optimal Sizing of Vanadium Redox Flow Battery Systems for Residential Applications Based on Battery Electrochemical Characteristics." Energies 9, no. 10: 857.
The low-temperature stability and precipitation behaviour of VIII and VII sulfate solutions are critical for the optimal operation of vanadium redox flow batteries. In this study, the kinetics of the VIII and VII sulfate precipitation processes have been studied at different temperatures and sulfate concentrations. Kinetic studies of the precipitation of stagnant vanadium(III) sulfate solutions followed a first-order rate law with rate constants on the order of 0.007 h−1 and an activation energy of about 14.6 kJ mol−1. Stirring the solutions at low supersaturation causes a ten-fold increase in the rate of precipitation and also resulted in a change in the precipitation mechanism from diffusion controlled to a surface reaction controlled mechanism with an activation energy of 37.0 kJ mol−1. Stagnant solutions at high supersaturation followed a second-order rate law with an activation energy of 27.0 kJ mol−1 for the first 30 % of the precipitation process. The process becomes first order in the last 70 % with an activation energy of 14.3 kJ mol−1, indicating a change in the reaction mechanism to a diffusion-controlled mechanism. Kinetic studies of the precipitation of vanadium(II) sulfate solutions showed that both stagnant and stirred solutions follow a first-order rate law with a low activation energy (10.7 and 14.5 kJ mol−1, respectively). This indicates a diffusion-controlled precipitation mechanism under both conditions.
Asem Mousa; Maria Skyllas-Kazacos. Kinetics of VIII and VII Sulfate Precipitation Processes in Negative Half-Cell Electrolyte of the Vanadium Redox Flow Battery. ChemElectroChem 2016, 4, 130 -142.
AMA StyleAsem Mousa, Maria Skyllas-Kazacos. Kinetics of VIII and VII Sulfate Precipitation Processes in Negative Half-Cell Electrolyte of the Vanadium Redox Flow Battery. ChemElectroChem. 2016; 4 (1):130-142.
Chicago/Turabian StyleAsem Mousa; Maria Skyllas-Kazacos. 2016. "Kinetics of VIII and VII Sulfate Precipitation Processes in Negative Half-Cell Electrolyte of the Vanadium Redox Flow Battery." ChemElectroChem 4, no. 1: 130-142.
This paper extends previous thermal models of the vanadium redox flow battery to predict temperature profiles within multi-cell stacks. This involves modelling the thermal characteristics of the stack as a whole to modelling each individual cell. The study investigates the thermal behaviour for two different scenarios: during standby periods when the pumps are turned off, and in a residential power arbitrage scenario for two types of membranes. It was found that the temperature gradient across the cells is most significant during the standby case, with the simulation results showing completely different thermal behaviours between the two systems.
Yitao Yan; Yifeng Li; Maria Skyllas-Kazacos; Jie Bao. Modelling and simulation of thermal behaviour of vanadium redox flow battery. Journal of Power Sources 2016, 322, 116 -128.
AMA StyleYitao Yan, Yifeng Li, Maria Skyllas-Kazacos, Jie Bao. Modelling and simulation of thermal behaviour of vanadium redox flow battery. Journal of Power Sources. 2016; 322 ():116-128.
Chicago/Turabian StyleYitao Yan; Yifeng Li; Maria Skyllas-Kazacos; Jie Bao. 2016. "Modelling and simulation of thermal behaviour of vanadium redox flow battery." Journal of Power Sources 322, no. : 116-128.
To date, no physical model has been proposed to describe the mechanism of shunt currents in bipolar electrochemical reactors with a common electrolyte manifold. In this paper, we show that under the influence of the cell voltage driving force, the bipolar electrode provides an internal electrical pathway that allows electrons to flow from the negative half-cell of one cell, to the positive half-cell of the adjacent cell, leading to self-discharge reactions that can occur even when the stack is at open-circuit. This is made possible, by the presence of the interconnecting channels and common electrolyte manifolds that enable the flow of hydrogen or other charge carrying ions to complete the circuit. The larger the number of cells in the cell stack, the larger the number of internal pathways for electrons and protons to flow, so the greater the shunt current losses.
Maria Skyllas-Kazacos; John McCann; Yifeng Li; Jie Bao; Ao Tang; Jie Bao And. The Mechanism and Modelling of Shunt Current in the Vanadium Redox Flow Battery. ChemistrySelect 2016, 1, 2249 -2256.
AMA StyleMaria Skyllas-Kazacos, John McCann, Yifeng Li, Jie Bao, Ao Tang, Jie Bao And. The Mechanism and Modelling of Shunt Current in the Vanadium Redox Flow Battery. ChemistrySelect. 2016; 1 (10):2249-2256.
Chicago/Turabian StyleMaria Skyllas-Kazacos; John McCann; Yifeng Li; Jie Bao; Ao Tang; Jie Bao And. 2016. "The Mechanism and Modelling of Shunt Current in the Vanadium Redox Flow Battery." ChemistrySelect 1, no. 10: 2249-2256.
Zhongbao Wei; Tuti Mariana Lim; Maria Skyllas-Kazacos; Nyunt Wai; King Jet Tseng. Online state of charge and model parameter co-estimation based on a novel multi-timescale estimator for vanadium redox flow battery. Applied Energy 2016, 172, 169 -179.
AMA StyleZhongbao Wei, Tuti Mariana Lim, Maria Skyllas-Kazacos, Nyunt Wai, King Jet Tseng. Online state of charge and model parameter co-estimation based on a novel multi-timescale estimator for vanadium redox flow battery. Applied Energy. 2016; 172 ():169-179.
Chicago/Turabian StyleZhongbao Wei; Tuti Mariana Lim; Maria Skyllas-Kazacos; Nyunt Wai; King Jet Tseng. 2016. "Online state of charge and model parameter co-estimation based on a novel multi-timescale estimator for vanadium redox flow battery." Applied Energy 172, no. : 169-179.
A dynamic plug flow reactor model for a single cell VRB system is developed based on material balance, and the Nernst equation is employed to calculate cell voltage with consideration of activation and concentration overpotentials. Simulation studies were conducted under various conditions to investigate the effects of several key operation variables including electrolyte flow rate, upper SOC limit and input current magnitude on the cell charging performance. The results show that all three variables have a great impact on performance, particularly on the possibility of gassing during charging at high SOCs or inadequate flow rates. Simulations were also carried out to study the effects of electrolyte imbalance during long term charging and discharging cycling. The results show the minimum electrolyte flow rate needed for operation within a particular SOC range in order to avoid gassing side reactions during charging. The model also allows scheduling of partial electrolyte remixing operations to restore capacity and also avoid possible gassing side reactions during charging. Simulation results also suggest the proper placement for cell voltage monitoring and highlight potential problems associated with setting the upper charging cut-off limit based on the inlet SOC calculated from the open-circuit cell voltage measurement.
Yifeng Li; Maria Skyllas-Kazacos; Jie Bao. A dynamic plug flow reactor model for a vanadium redox flow battery cell. Journal of Power Sources 2016, 311, 57 -67.
AMA StyleYifeng Li, Maria Skyllas-Kazacos, Jie Bao. A dynamic plug flow reactor model for a vanadium redox flow battery cell. Journal of Power Sources. 2016; 311 ():57-67.
Chicago/Turabian StyleYifeng Li; Maria Skyllas-Kazacos; Jie Bao. 2016. "A dynamic plug flow reactor model for a vanadium redox flow battery cell." Journal of Power Sources 311, no. : 57-67.
Aluminum smelters worldwide are challenged by increasing ecological and economical pressure. Higher line amperages gain production output but increase the HF load on dry scrubbers. Another important factor today is the tight alumina market, hence it is necessary to accommodate dry scrubber and potline operations to different alumina sources and qualities regarding their HF generation and scrubbing efficiency as well as its impact on bath chemistry. The TRIMET smelter optimized dry scrubber operations by the use of a laser based HF measuring system in each of the 20 filter modules. Based on the HF level in the outlet of each filter the alumina flow to each filter is pulse-duration modulated, thus tightly control the HF emission level in the outlet gas. This paper describes the application of the new measuring and control principle and its impact on HF scrubbing efficiency and bath chemistry.
Martin Iffert; Markus Kuenkel; Barry Welch; Maria Skyllas-Kazacos. Reduction of HF Emissions from the TRIMET Aluminum Smelter (Optimizing Dry Scrubber Operations and Its Impact on Process Operations). Essential Readings in Light Metals 2016, 968 -974.
AMA StyleMartin Iffert, Markus Kuenkel, Barry Welch, Maria Skyllas-Kazacos. Reduction of HF Emissions from the TRIMET Aluminum Smelter (Optimizing Dry Scrubber Operations and Its Impact on Process Operations). Essential Readings in Light Metals. 2016; ():968-974.
Chicago/Turabian StyleMartin Iffert; Markus Kuenkel; Barry Welch; Maria Skyllas-Kazacos. 2016. "Reduction of HF Emissions from the TRIMET Aluminum Smelter (Optimizing Dry Scrubber Operations and Its Impact on Process Operations)." Essential Readings in Light Metals , no. : 968-974.