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Keeping in view, the recent energy conditions and contribution of non-fullerene acceptors (NFAs) towards organic solar cells (OSCs), a series of NFAs (D1-D9) was designed. The novel fused ring NFAs (D1-D9) having A-D-A architecture were designed by structural engineering of R molecule with effective benzothiophene based acceptor moieties. For current study, all the calculations were accomplished at M06/6-311G (d,p) level. Different computational approaches like density of states (DOS), binding energy (Eb), transition density matrix (TDM), absorption spectra (UV–Vis), electronic properties (FMOs) and open circuit were performed to investigate the photovoltaic response of newly designed D1-D9 chromophores. The terminal substitution of end-capped acceptors exhibited a reduction in energy gap (ΔE = 2.222–1.986 eV) with high electron mobility rate in all the derivatives (D1-D9) than that of R. All the designed chromophores exhibited wider absorption spectrum (λmax = 845.039–786.552 nm) along with lower excitation energy as compared to R (λmax = 770.040 nm) except D1 and D9. Interestingly, lower binding energy (Eb = 0.419–0.473 eV) accompanying with higher excition dissociation rate was seen in derivatives than that of reference compound. Moreover, a comparable value of Voc was noted in derivatives when calculated via LUMOacceptor–HOMOPBDBT. Among all fore-said chromophores (D1-D9), D4 exhibited lowest binding energy and thus ensured easier and faster excition dissociation rate along with highest Voc (1.586 V). In cessation, this structural modification by utilizing various acceptors played a significant role in obtaining auspicious photovoltaic response in compounds. Hence, our study encourages the experimentalists for synthesizing these proposed organic systems for the attaining high efficacy photovoltaic devices.

Herein, a series of pyrazoline based non-fullerene compounds (THP1-THP8) having ladder-like backbone was designed by structural modulation with various electron accepting moieties. The density functional theory (DFT) and time-dependent functional theory (TD-DFT) study was executed at M06/6-311G(d,p) level for structural optimization and to determine the electronic and optical characteristics of the pyrazoline based chromophores. The optimized structures were employed to execute frontier molecular orbital (FMO), transition density matrix (TDM), density of state (DOS), open circuit voltage (Voc) and reorganization energy analyses at the aforementioned level of DFT to comprehend the photovoltaic (PV) response of THP1-THP8. The red-shifted absorption spectrum (512.861–584.555 nm) with reduced band gap (2.507–2.881 eV) allow considerable charge transferal from HOMO to LUMO in all the studied compounds. Global reactivity parameters (GRPs) demonstrated high softness with considerable reactivity in THP1-THP8. Moreover, remarkable Voc values (2.083–2.973 V) were noted for all the derivatives (THP1-THP8). However, THP2 with lowest energy gap (2.364 eV), highest λmax (617.482 nm) and softness (0.423 eV) values is considered good candidate among afore-said chromophores. Hence, the studied chromophores with efficient properties are appropriate for experimentalists in terms of manufacturing of efficient OSCs.

The adoption of photovoltaic (PV) solar systems has been rapidly increasing due to their cost-effectiveness and easy installation. However, the non-linearity of PV panels can hinder their ability to provide maximum power output. To achieve optimal efficiency, it is crucial to track the control point based on irradiance and temperature values. This study proposes an analytical control method that employs the open circuit voltage to track the maximum power point of a PV panel that is connected to a DC microgrid via a DC–DC boost converter. The proposed model considers the temperature effect on both diode saturation current and current generated by irradiance for higher sensitivity. To validate the accuracy of the proposed model, the PV panel installed at the Technopark campus of Gazi University was used for experimentation. The performance indicators, mean absolute percentage error (MAPE) and R2, were calculated to assess the differences between the values calculated from the proposed model and those observed from the experiments. The results indicate an error value of 3.9% and a compatibility of 95.9% based on MAPE and R2, respectively. These findings demonstrate the success of the proposed model. [ABSTRACT FROM AUTHOR]

Because of its exceptional qualities, such as high energy density, extended lifespan, and low self-discharge, lithium-ion (Li-ion) batteries have grown in popularity in recent years. However, the maximum temperature that these batteries can endure while in use is essential to their safety and effectiveness. The Taguchi technique, a statistical strategy that permits efficient evaluation of multiple experimental parameters, has been utilized by the researchers to improve this. This study has changed six input elements, each with five levels, including battery diameter, height, capacity, activation energy, density, and final state of charge, in order to identify the best settings to optimize the maximum temperature of lithium ion batteries. The study's findings have been validated by using an analysis of variance (ANOVA). The study has discovered that the diameter and the height of the battery have been the most critical parameters in determining the maximum temperature of the battery. This approach discovers perfect circumstances that can increase Li-ion battery performance and potentially broaden their use in a variety of applications. In order to simulate the design, the researchers have used the COMSOL Multiphysics software to create a Li-ion battery pack that could withstand 50°C and have conducted a transient analysis over 0.2 hours in order to observe the increase in temperature due to internal resistance, electrochemical reactions, and ambient temperature. This approach can eliminate design problems that arise from the traditional trial-and-error method by tuning the control parameters examined in this study. This approach can streamline the design process of Li-ion battery packs for specific applications, making it more efficient. [ABSTRACT FROM AUTHOR]

The needs of the population and industry for electrical energy are limited by oil and gas reserves, which leads to the need to use renewable energy sources. Myanmar is one of the developing countries in Asia. Its specific power consumption is low compared to neighboring countries. Currently, one of the most important tasks of the electric power industry is to ensure reliable, uninterrupted power supply to all industrial and domestic facilities. At the same time, the development of small solar photovoltaic installations (PMT), operating both in parallel with the grid and in autonomous mode, can improve the power supply of closely located consumers more efficiently and faster than the development of a large power system. Therefore, the work devoted to the improvement of the equipment of a small solar photovoltaic installation is relevant and of great practical importance.

In this study, the temperatures of the front glass, back sheet, and solar cell (SC) in the rear electrical contact of the PV module during heating, and the open circuit voltage and short circuit current corresponding to these temperatures were experimentally investigated. Measurements were conducted in the city of Termez in conditions of an air temperature of 30ºC and solar radiation intensity of 850-950W/m2 . Two mono c-Si PV modules with the same electric power were selected for the experiment. Three K-type chrome and alumn combined thermocouples were used to measure the temperatures in the layers of the first PV module. During the observations, it was found that the temperature of the PV module glass differs from the back sheet temperature by ~20ºC, and from the temperature of the back electrical contact of the SC by ~25ºC. Also, according to the temperature difference, the open circuit voltage of the PV module decreased from 21V to 19.3V, and the short circuit current increased from 0.65A to 0.75A. During the experiment, the values of electric power changed by ~11-11.6W.

A microbial fuel cell (MFC) is a renewable source of energy that produces electricity without harming the environment. This review paper describes the importance of MFCs for future power sources. The construction methods, history of MFC, different configuration of MFC and voltage generation of single-chamber as well as the two-chamber MFC have been discussed. Due to the bio-electrochemical features of the MFCs, when an electric load is applied to stack MFCs, Stack MFC’s voltage does not remain constant over time (known as reversal of voltage). Therefore, researchers have proposed various power management systems (PMS) to raise the voltage of the MFC to avoid voltage reversal. The future direction is focus on the design of a PMS adapted for MFC optimal operation using ultralow power consumption components.

The power conversion efficiency (PCE) of ternary polymer solar cells (PSCs) with non-fullerene has a phenomenal increase in recent years. However, improving the open circuit voltage (Voc) of ternary PSCs with non-fullerene still remains a challenge. Therefore, in this work, machine learning (ML) algorithms are employed, including eXtreme gradient boosting, K-nearest neighbor and random forest, to quantitatively analyze the impact mechanism of Voc in ternary PSCs with the double acceptors from the two aspects of photovoltaic materials. In one aspect of photovoltaic materials, the doping concentration has the greatest impact on Voc in ternary PSCs. Furthermore, the addition of the third component affects the energy offset between the donor and acceptor for increasing Voc in ternary PSCs. More importantly, to obtain the maximum Voc in ternary PSCs with the double acceptors, the HOMO and LUMO energy levels of the third component should be around (−5.7 ± 0.1) eV and (−3.6 ± 0.1) eV, respectively. In the other aspect of molecular descriptors and molecular fingerprints in the third component of ternary PSCs with the double acceptors, the hydrogen bond strength and aromatic ring structure of the third component have high impact on the Voc of ternary PSCs. In partial dependence plot, it is clear that when the number of methyl groups is four and the number of carbonyl groups is two in the third component of acceptor, the Voc of ternary PSCs with the double acceptors can be maximized. All of these findings provide valuable insights into the development of materials with high Voc in ternary PSCs for saving time and cost. [ABSTRACT FROM AUTHOR]

• Al/BaTi 1-2x Fe x Nb x O 3 /Ag is an excellent bulk ferroelectric photovoltaic device configuration. • Increment of aliovalent Fe3+ and Nb5+ ionic substitutions reduces the bandgap of 0.075BFNT ceramics to ∼2.55 eV and broadens the visible spectrum absorption. • The photocurrent density of Al/0.075BFNT/Ag photovoltaic cell is about ∼ 2.2 times higher than that of pure BT. • A high photovoltaic power of ∼ 12 μW/cm2 was achieved. The generation of above bandgap photovoltage using bulk ferroelectric materials has become a subject of great interest, however, their photocurrent density is limited by a broad bandgap and poor conductivity. To overcome this limitation, we replaced aliovalent metal ions (Fe3+ and Nb5+) at the B-site of robust ferroelectric BaTiO 3 and fabricated an Al/BaTi 1-2x Fe x Nb x O 3 /Ag photovoltaic device. Both the experimental and the theoretical studies showed that bandgap was lowered to ∼2.55 eV and hence absorption of wide energy range of the solar spectrum was attained. An apt top electrode, reduced bandgap and domain size resulted in greater photocurrent density of 1.46 μA/cm2 and photovoltage of 8.31 V for Al/0.075BFNT/Ag solar cell in unpoled condition. This research suggest that reduced band gap, mixed structural phases and nano-sized domains suffices greatest PV power output while the large polarization and poling are not necessary prerequisites. [ABSTRACT FROM AUTHOR]

This study reported the activity of catalysts synthesized from platinum and molybdenum alloys in different atomic ratios and used as cathode electrocatalysts in the PEMFC. The structural properties of PtMo/C and Pt/C catalysts were analyzed by XRD analysis. The composition and distribution of these alloys in Vulcan XC-72R Carbon were determined by SEM and EDX techniques. CV studies assessed electrochemical properties such as ORR and ECSA activity. The performance of PEMFC cathodes that supplied pure hydrogen and oxygen was examined using polarization curves at different temperatures. Another way to improve the cathodic reaction is to use ozone as a potent oxidizing agent. It was measured that the OCV of the H 2 /O 3 PEM fuel cell was 1.60 V, much greater than the open circuit voltage of the traditional H 2 /O 2 PEM fuel cell. The PtMo/C catalyst achieved its highest power density of 137 mWcm−2 at 70 °C, 128 mWcm−2 at 60 °C, 101 mWcm−2 at 50 °C, and 85 mWcm−2 at 40 °C when exposed to H 2 /O 2. As the temperature of the cell was raised, it was seen that the catalyst's catalytic activity increased. The maximum power density was detected to be inversely related to the rise in temperature when ozone was used. At low current densities, however, ozone was observed to greatly boost activation polarization. [Display omitted] • The use of PtMo/C catalyst as a cathode affects the power density of the cell. • PtMo/C produces the highest power density in a PEM fuel cell when using H 2 /O 2. • Using H 2 /O 3 , the PtMo/C catalyst gave the best results in the low-current density region. • The PtMo/C catalyst has the best activity at increasing cell temperature when using H 2 O 2. [ABSTRACT FROM AUTHOR]

A series of alkyl‐group‐functionalized, aniline‐ and indoline‐donor‐based, unsymmetrical visible‐light‐active squaraine dyes, AM1‐3, were designed and synthesized. Dye‐sensitized solar cell (DSSC) devices were fabricated with both I−/I3− and [Cu(tmby)2]+/2+ electrolytes. DSSC devices sensitized with the AM1 and AM2 dyes showed relatively high‐power conversion efficiency of 7.44 % and 7.22 %, respectively with I−/I3− in the absence of chenodeoxycholic acid (CDCA) than those of the AM3 dye (5.41 %). The [Cu(tmby)2]+/2+ electrolyte along with poly(3,4‐ethylenedioxythiophene) (PEDOT) as cathode material showed excellent open‐circuit potentials (VOC) of 1030, 1025, and 1001 mV with the DSSC efficiency of 8.05 %, 7.96 %, and 5.84 %, respectively, for the AM1, AM2, and AM3 dyes in the absence of CDCA. Here, the AM1 dye exhibited the maximum DSSC efficiency of 8.05 % and VOC of 1030 mV, which is the highest obtained efficiency and VOC for the visible‐light active zwitterionic unsymmetrical‐squaraine dye with copper‐based electrolyte. [ABSTRACT FROM AUTHOR]

This paper presents the results of electrical simulations at different active thickness layers of hybrid photovoltaic devices using GPVDM software. A combination of inorganic n-type semiconductor SiGe and organic p-type semiconductor PTAA has been chosen to be simulated in this research work. The thickness of SiGe and PTAA varies from 100 nm – 500 nm and 1000 rpm – 5000 rpm. The results show that the thickness of both semiconductor affects the electrical properties. Higher current density, Jsc, can be obtained as the thickness of SiGe increases. PTAA as an active layer had affected the value of open-circuit voltage, Voc. The SiGe combination with lower rpm depicted a higher value of Voc than the other combinations. The FF and efficiency rate of the solar panel is also presented in this work. This research focuses on the thickness combination of both semiconductors layer on the performance of its electrical characteristics.

The construction of an aluminum-sodium hypochlorite battery is addressed. The battery was made from household chemicals and products obtained from a typical supermarket. The proposed small-scale battery design is easy to assemble and only one cell is needed to light a red light emitting diode (LED). [ABSTRACT FROM AUTHOR]

The tandem organic solar cell could absorb the complementarity sunlight spectra by the sub-cells based on the different energy gap of the active-layer materials. In this work, a wide-band gap of the organic material PTB7-Th: PC71BM is used as the front sub-cells active layer, and the narrow-band gap of PTB7-Th: IEICO-4F is used as the rear sub-cells active layer. The front and rear sub-cells present the complementary absorption spectra leading to the sufficiently improvement of the sunlight absorption. MoO3/Au/ZnO multilayer film is the interconnecting layer. ZnO film was prepared by the sputtering method is smaller root-mean-square than that of the film prepared by the solution synthesis, resulting in a good contact interfacial between the sub-cells. This is in favor of the JSC and FF of the tandem organic solar cell. Importantly, the short-circuit current density of the tandem solar cell is handily controlled by the active-layer concentration of the front sub-cell, the tandem cell exhibits an optimal PCE of 11.77% with a large VOC of 1.45 V. [ABSTRACT FROM AUTHOR]

Many problems arise in the operation of photovoltaic systems. Each of these problems affects the operation of photovoltaic systems by reducing the power of the entire system. Some problems can be avoided during the design of photovoltaic systems. For example, when designing photovoltaic systems, it is possible to eliminate the shading of photovoltaic panels from surrounding objects. It is also necessary to look at the shading from neighboring photovoltaic panels when designing photovoltaic systems. It is necessary to calculate the inclination of the sunlight based on the position of the sun and calculate the distance between the two panels accordingly. However, some problems appear during the operation of photovoltaic systems. These problems can be partially eliminated. The magnitude of the series resistance can be eliminated by reducing the transition resistance throughout the system. The paper describes these problems and their possible solutions in practice. In the practical part, we focused on simulations and experiments in the field of photovoltaic systems (PV). The simulations focused on both the influence of temperature and the series resistance of photovoltaic panels on the production of electricity. The experiments were focused on the influence of various faults/defects on the power and V-A characteristics of photovoltaic panels connected in strings. The paper also discusses the impact of bypass diodes on the operation of photovoltaic systems and determines the need to use bypass diodes. [ABSTRACT FROM AUTHOR]

The efficiency of solar cells depends on the quality of passivation of surface. The quality of passivation is analyzed as a function of the dependence of the open circuit voltage on the light intensity. Therefore, in this article, the dependence of the photoelectric parameters of the silicon-based solar cell on the light intensity was studied. According to the obtained results, it was found that the variation of the short-circuit current through light intensity is equal to 25.6 mA/suns·cm². The agreement of the results obtained in research and modeling with the results of experiments proves the validity and correctness of the model. In this paper, the Sentaurus TCAD model of a silicon-based solar cell is experimentally verified. So, the dependence of the open circuit voltage of the silicon-based solar cell on the light intensity was studied through modeling and experiment. The functional dependence of the open circuit voltage obtained in the modeling satisfied the experiment. Therefore, the model of the solar cell created in Sentaurus TCAD is suitable for research. So, we can use model created in Sentaurus TCAD in our further researches. In addition, the fill factor of solar cell increased with increasing intensity. This proves that the resistive properties of the solar cell are improving. [ABSTRACT FROM AUTHOR]

Vanadium redox flow batteries (VRFB) are a fertile energy storage technology especially for customized storage applications with special energy and power requirements. The dimensioning and control of these storages is mostly calculated beforehand using battery models in embedded simulation structures. To cover various stack designs, chemistries, application strategies and system architectures, battery simulation models should be validated with different experimental input data and thus show universal functionality. In this study the functionality of a grey box VRFB model using current, voltage and state of charge (SOC) of a 10 kW/100 kWh VRFB as input data are validated for an adapted input data set using of a 5 kW/10 kWh VRFB. This model is designed for stationary applications of VRFB only. The contribution of this study is (i) to apply a suitable SOC conversion method to the raw data from the used 5 kW VRFB system, (ii) to adapt the modeling code for broader use and integration of the SOC conversion, (iii) to validate the functionality and (iv) to investigate the influence of constant current and constant voltage phases in the raw data on the accuracy of the model. A comparison of experimental data between different redox flow batteries shows that most VRFB measure the open circuit voltage (OCV) to calculate the SOC of the battery. Using the calculated SOC as an input data the proposed simulation model need to be adapted and a method is applied to use OCV input data for model validation. Although simulation models in general often assume linearity between SOC and OCV, the study showed sufficient accuracy using polynomic fitting of second order. Applying a parametrization process the results of the simulation model are compared to the raw data and the scope of application of the grey box VRFB model is defined. While using the dominant constant current phase for the charging and discharging cycle, the grey box simulation model has been sufficiently parametrized and validated for adapted input data. [ABSTRACT FROM AUTHOR]

[Display omitted] • Application of [Fe 4 S 4 ] to metal-ion batteries is studied using DFT calculations. • Embedding [Fe 4 S 4 ]2+ clusters in metal–organic frameworks generates high voltage. • The electrochemical performance is based on an intercalation mechanism. • Among the screened material pairs, Zn2+-BMOF shows the highest efficiency. [Fe 4 S 4 ] clusters have served as molecular batteries and charge transfer centers in many biosystems. However, their potential as electrode materials has been overlooked amidst the ever-increasing studies on various materials in the search for efficient battery compositions. To evaluate their electrochemical efficiency as electrode materials, we focused on the use of two important oxidation states, [Fe 4 S 4 ]2+ and [Fe 4 S 4 ]⁰, in a series of Li-, Na-, K-, Mg-, Ca-, and Zn-ion batteries. We also assessed the effect of metal–organic framework (MOF) formation on their performance by studying [Fe 4 S 4 ]2+-1,4-benzenedithiolate MOF (BMOF) and its carboxylate-based counterpart (CMOF). Our model-based Density Functional Theory (DFT) calculations indicated that oxidation of the cluster to [Fe 4 S 4 ]2+ and MOF formation significantly improve the electrochemical efficiency of the cluster. Among the studied electrode materials and metals, the BMOF combination with Mg0 and Zn2+ presented the best electrochemical performance. Notably, our periodic calculations indicated an open circuit voltage of 4.32 V for the Zn2+-BMOF system, suggesting a promising performance for BMOF compared to other cathode/negative electrode materials. Our atomic and electronic structure analyses indicated that intercalation is the underlying electrochemical mechanism. [ABSTRACT FROM AUTHOR]

In the search for next-generation energy storage devices, superior-performance alternative electrode materials based on two-dimensional materials for rechargeable metal-ion batteries are essential. Here, we explored group III and IV functionalization of 2D Ti 2 B, Ti 2 BX 2 (X=Si, Ge, P, As) as anode materials for Li and Na ion batteries using first-principles calculations. The structures had excellent metallic properties and demonstrated energetically favorable adsorptions for metal ions. Analyzing charge transfer and electronic band structures, silicon and phosphorous-functionalized Ti 2 B (Ti 2 BSi 2 and Ti 2 BP 2) showed the most potential. The energy band diagrams showed that both Ti 2 BSi 2 and Ti 2 BP 2 had metallic characteristics after Li and Na-ion adsorption, which offered considerable advantage for rechargeable-ion batteries. The structures exhibited low energy barriers for Li and Na-ion migration. The minimum energy barriers calculated for Na were 0.08 eV for Ti 2 BSi 2 and 0.24 eV for Ti 2 BP 2. Theoretical specific capacity and open circuit voltage were calculated using maximum layer adsorption. For both Li and Na, high values of specific capacity and low values of open circuit voltage (¡ 1 V) were found. Ti 2 BSi 2 had the best performance, with a theoretical specific capacity of 1647.10 and 1317.68 mA h/g for Li and Na, respectively. Its open circuit voltages for Li and Na were 0.65 and 0.38 V. The insights of this study will be beneficial in fabricating high-performing Ti 2 BX 2 -based anodes for rechargeable Li and Na ion batteries. [Display omitted] • Functionalized 2D MBene Ti 2 B were explored for potential applications as anode materials in rechargeable ion batteries. • Functionalized Ti 2 B structures were both dynamically and energetically stable, with excellent metallic characteristics. • High theoretical specific capacity, low open circuit voltage, and low diffusion barriers were revealed for the proposed functionalized structures. • Comparative analysis with literature verifies that the proposed structures demonstrated significant promise as anode materials. [ABSTRACT FROM AUTHOR]

The paper presents an overview of studies of the multi-junction (MJ) solar cells (SC) with IV characteristics having nonlinear peculiarities. It is shown that such peculiarities can arise either due to hetero-interface barriers (HB) for majority charge carriers or due to problems with tunnel diodes (TD). It is usually difficult to identify which of these hetero-structural objects is the cause of this nonlinearity, since the peculiarities appear similarly in the IV characteristics of MJ SC. The experimental method presented in this work is based on the study of IV characteristics during the overheating of MJ SCs. The behavior of nonlinear peculiarities caused by an imperfect TD or an HB is fundamentally different during the overheating of SCs, which makes it possible to identify the type of hetero-structural object. Since the number of hetero-interfaces in MJ SC is large, a method determining the position of problematic objects in the MJ structure was also developed. The method is based on the illumination of individual subcells using different laser wavelengths. Both methods considered were tested experimentally on GaInP/GaAs/Ge SCs. • Heterobarriers and tunnel diodes can be responsible for nonlinear peculiarities arising in the IV characteristics of MJ SC. • The search for non-optimized layers position inside the SC structure can be performed using specialized structures. • Non-optimized tunnel diode could lead to the presence of an open-circuit voltage drop. • Temperature reaction of IV characteristics allows determining the type of object that gives a nonlinear peculiarity. • Analysis of such a reaction allows us to determine the position of non-optimized hetero-barriers. [ABSTRACT FROM AUTHOR]

LiFePO4 batteries are increasingly utilized in electric vehicles due to their superior safety. Accurate state estimation is the basis for the safe and reliable application of LiFePO4 batteries. However, the flat voltage characteristics of LiFePO4 batteries lead to state estimation closed-loop correction as its inherent contradiction. To address this challenge, a model-based SOC estimation method combining proportional-integral-differential (PID) observer and improved extended Kalman filter (EKF) is developed according to different open-circuit-voltage (OCV) ranges, specific processes include: First, an exponentially weighted moving average algorithm with a temperature compensation factor is presented to compensate for the errors in the identified OCV. Secondly, the combination of the PID observer and EKF is chosen adaptively to update SOC within distinct OCV ranges, differentiated by the identified OCV. To achieve optimization of the PID parameters and temperature compensation factors across varying temperatures, an enhanced whale optimization algorithm is developed. To validate the developed method, a series of experiments are performed across a range of temperatures and with multiple driving profiles. The results show that the developed method not only guarantees maximum absolute error of <3 %, but also can converge quickly in the early stage. • A temperature compensation factor (T c) is used to reduce the error of identified OCV based on EWMA-FFRLS. • A PIDO combined with an improved AEKF is presented to accelerate the SOC convergence speed. • An AEKF-PIDO-integrated US-EKF framework is developed to enhance SOC estimation of LiFePO4 battery. • An improved WOA is introduced to adjust the PIDO parameters and T c at different temperatures. [ABSTRACT FROM AUTHOR]

A battery source is an indispensable component in electric vehicles and its efficient usage results in improvement of battery life. The amount of energy stored in batteries, including their state of charge and efficiency, are critical metrics for evaluating vehicle performance. This article presents an automated motor-generator linked technique for estimating battery-related parameters, which is an essential aspect of eco-routing in electric vehicles. This system enables discharging of a battery at various current rates by constant resistive loads which are electronically applied. The charging process however uses a charger attached to various sensors for estimating the current. The coulomb counting method has been used which provides information of State of Charge and Coulombic Efficiency of the test battery. Since battery behavior is dynamic; the energy source was charged and discharged over numerous cycles at various current rates. The experimental set-up uses sensors for accurate data acquisition. In addition to the experimental set-up, an electrical circuit battery model has also been simulated in this work. All simulation as well as post processing tasks have been done in the Arduino-MATLAB environment. The main highlight of this system is that the system is portable, easy to operate, low cost and can be used to test all types of batteries. The proposed system is simple and has yielded good results. The battery parameters obtained prove to be vital for range determination in eco-routing of electric vehicles among other applications.

The photovoltaic (PV) panels are expected to be the most important systems to meet global energy demand by converting solar energy into electricity. The main obstacle to the widespread deployment of the PV systems its the limited efficiency, which are greatly affected by the solar radiation and the operating temperature. The full knowledge of the performance, efficiency and output power of photovoltaic modules and the extent of their change with the fluctuations of solar radiation and temperature is necessary to determine the optimal size of the system and avoid the financial risks of the project. This paper investigated numaricaly and experimentaly the influence of operating temperature and solar radiation on the output power and efficiency of polycrystalline PV panels in Baghdad-Iraq. The PVsyst software was used to simulate a model implementing simulation results presented the impact of variations temperature and solar radiation in the curves of I-V, P-V and efficiency. In order to verify the reliability of the simulated results with experimental ones, several measuring devices have been used to conduct field experiments in the outdoor conditions. It were used to determine the characteristics and performance of a 120W polycrystalline PV panel for different ranges of solar radiation and operating temperature. The simulation results showed that the current, voltage, output power and efficiency increased with increasing solar radiation, while they decreased with increasing temperature except the current that was increased. The experimental and simulated results were identical in terms of the effect of temperature and solar radiation on the current, voltage, output power and efficiency of the PV panel. The experimental tests showed that when the temperature is increased by 1°C, the current was increased by about 0.068%, the voltage decreased by 0.34%, the output power decreased by 0.489% and the efficiency decreased about 0.586%. The experimental results displayed that the parameters of the PV panel under real operating conditions behave differently than in the standard test conditions (STC), as they are strongly affected by weather fluctuations in terms of temperature and solar radiation

In this theoretical research, four distinct acceptor molecules (M-M3) having structural configuration A 2 -D-π-A 1 -π-D-A 2 have been designed through terminal acceptor and linker alteration. The DFT-based approach B3LYP/6–31 G (d, p) has been used to study the photovoltaic properties of designed molecules. A number of characteristics of these molecules have been assessed comprehensively. The designed molecules M-M3 have exhibited lower energy gap (1.56–1.63 eV) as compared to the reference molecule (E g = 1.70eV). A red shift in absorption was observed for all the molecules (λ max = 964 –1005 nm) as compared to the reference molecule (λ max = 693 nm). Nearly identical outcomes from density of states and frontier molecular orbitals for all the altered molecules show that electron density is evenly dispersed across the entire molecules. Additionally, their slightly greater dipole moment and smaller excitation energy as compared to reference molecule are responsible for their remarkable charge transfer because of better separation of electron-hole pair (exciton). Calculating open circuit voltage of the examined acceptor molecules with respect to P113 donor have revealed that all the newly proposed molecules M-M3 exhibit higher V OC (1.25–1.36 eV) and FF. The results of this study imply that the fabrication of solar cells using these designed acceptor molecules may result in high photovoltaic yield. [Display omitted] • Four novel diketopyrrolopyrrole based acceptor molecules (M-M3) were proposed. • All the molecules were analyzed computationally by Gaussian 09 using DFT. • Designed molecules exhibited lower band gap and a bathochromic shift in λ max. • Designed molecules show raised open circuit voltage and FF. [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of single-junction perovskite solar cells (PSCs) has reached 26.1% in small-scale devices. However, defects at the bulk, surface, grain boundaries, and interfaces act as non-radiative recombination centers for photogenerated electron-hole pairs, limiting the open-circuit voltage and PCE below the Shockley–Queisser limit. These defect states also induce ion migration towards interfaces and contribute to intrinsic instability in PSCs, reducing the quasi-Fermi level splitting and causing anomalous hysteresis in the device. The influence of defects becomes more prominent in large-area devices, demonstrating much lower PCE than the lab-scale devices. Therefore, commercializing PSCs faces a big challenge in terms of rapid decline in working performance due to these intrinsic structural defects. This paper provides a comprehensive review of recent advances in understanding the nature and the classification of defects, their impact on voltage losses, device parameters, intrinsic stability, and defect quantification and characterization techniques. Novel defect passivation techniques such as compositional engineering, additive engineering, post-treatments, dimensionality engineering, and interlayer engineering are also reviewed, along with the improvements in PCE and stability based on these techniques for both small-area devices and large-area roll-to-roll coated devices.

Photovoltaic (PV) systems can generate less energy than expected owing to inefficiency of the inverter, deterioration of the PV modules or conditions of partial shading and soiling. The monitoring and diagnosis techniques of PV systems are therefore quite important to recognize the causes of the performances reduction and optimize the PV energy production. For a more in-depth diagnostic capability, it would be necessary to know the short-circuit current (Isc) and the open-circuit voltage (Voc) of the PV system. These quantities are indeed useful to recognize non-uniform operating conditions of the PV modules (partial shadings, malfunctions, generic electro-optical mismatch conditions), estimate the PV module junction temperature and the voltage temperature coefficient. However, so far, these quantities cannot be measured by the inverter in operative conditions. With this contribution we propose and test a new electronic interface for a more advanced diagnostics of the PV system to be easily installed between the PV string and the inverter, able to measure the values of Isc and Voc as well as the inverter voltage, current and power working points, avoiding any downtime of the PV system and minimizing the power losses during the diagnosis activity. [ABSTRACT FROM AUTHOR]

The state of charge (SOC) is critical for the safety and reliable utilization of the battery. However, SOC estimation accuracy of lithium iron phosphate (LiFePO4) battery is a challenging task because of its flat voltage plateau and its performance is affected greatly by temperature. An improved open circuit voltage (OCV) combined with coulomb counting (CC) method based on the dual input model of ambient temperature and OCV is proposed. This approach is employed to obtain the initial value of SOC based on the dual input model over a wide range of temperature, and to establish SOC estimation model of modified CC with Simulink. The temperature entropy coefficient and differential analysis has been analyzed under different SOC conditions. The SOC maximum errors predicted by the proposed OCV-CC method maintain within 3.10%, while the maximum errors of the traditional OCV-CC increase from 4.78% to 23.64% under the temperature of 35°C ~−15°C. The results show the estimation accuracy of SOC using the proposed OCV-CC method is improved obviously, especially under low temperature. [ABSTRACT FROM AUTHOR]

This paper present device model simulation describing the current-voltage characteristics of polymer/fullerene bulk heterojunction solar cell. In the research paper an organic photovoltaic device with PPV/PCBM [poly (2-methoxy-5-{3',7'-dimethyloctyloxy}-p-phenylene vinylene) and {6,6}- phenyl C61-butyric acid methyl ester] was simulated via Silvaco TCAD 2-D simulation tool. PCBM acts as acceptor and PPV is donor. The models used to simulate the device were Langevin for recombination, s.binding and a.singlet. Simulation of these type of devices is an vital approach to project and predict the cell performance. Under the illumination of one sun (AM 1.5) the simulated organic cell showed a short circuit current density (JSC) of 28 A/m2, open circuit voltage (VOC) of 0.84 Volt and a fill factor (FF) of 52.51%, the resulting maximum efficiency of the PPV/PCBM organic solar cell is 1.22%. [ABSTRACT FROM AUTHOR]

Herein, based on the reviewed literature, the current marketability challenges faced by kesterite CZTS based-solar cells is addressed. A knowledge update about the attempts to reduce the open circuit voltage deficit of kesterite CZTS solar cells will be addressed, with a focus on the impact of Cu/Zn order/disorder and of Se doping. This review also presents the strengths and weaknesses of the most commercially attractive synthesis methods for synthesizing thin kesterite CZTS films for photovoltaic applications. [ABSTRACT FROM AUTHOR]

State of Charge (SoC) is a parameter used to determine the current capacity on a battery as well as indicate the operational characteristics. The SoC is an important parameter for optimizing battery utilization in many applications requiring DC current source. However, estimating the SoC value is the major problem since it cannot be measured directly. In this study, we proposed SoC measurement method based on analysis internal resistance of battery. The internal resistance is correlated with the parameters of the magnitude of the terminal voltage and open circuit. Both voltages come from the influence of current during the charging-discharging process. We report that the proposed method has successfully obtained the correlation between the SoC and the internal resistance value for two process, which are the charging- and discharging process. [ABSTRACT FROM AUTHOR]

Metal halide perovskites with bandgap of ≈1.8 eV are competitive candidates for indoor photovoltaic (IPV) devices, owing to their superior photovoltaic properties and ideal absorption spectra matched to most indoor light sources. However, these perovskite IPVs suffer from severe trap induced non-radiative recombination, resulting in large open-circuit voltage (V OC ) losses, particularly under low light intensity. Herein, an effective approach is developed to minimizing trap density by modifying the buried interface of perovskite layer with bifunctional molecular 2-(4-Fluorophenyl)ethylamine Hydrobromide (F-PEABr). The benzene ring of F-PEABr molecules can firmly anchor at the hole transporting layer by π-π stacking interaction, and the other ends can passivate the defects on the buried interface of perovskite layer. Based on that, the F-PEABr modified perovskite IPVs achieved power conversion efficiency (PCE) of 42.3% with a remarkable V OC of 1.13 V under 1000 lux illumination from a 4000 K LED lamp. Finally, perovskite IPV mini-modules with area of 10.40 cm 2 are demonstrated with a PCE of 35.2%. This interface modification strategy paves the way for crafting high-performance perovskite IPVs, holding great potential for self-powered internet of things applications., (© 2024 Wiley‐VCH GmbH.)

In order to enhance the overall efficiency of colloidal quantum dots solar cells, it is crucial to suppress the recombination of charge carriers and minimize energy loss at the interfaces between the transparent electrode, electron transport layer (ETL), and colloidal quantum dots (CQDs) light-absorbing material. In the current study, ZnO/SrTiO 3  (STO), ZnO/WO 3  (TO), and ZnO/Zn 2 SnO 4  (ZTO) bilayers are introduced as an ETL using a spin-coating technique. The ZTO interlayer exhibits a smoother surface with a root-mean-square (RMS) value of ≈ 3.28 nm compared to STO and TO interlayers, which enables it to cover the surface of the ITO/ZnO substrate entirely and helps to prevent direct contact between the CQDs absorber layer and the ITO/ZnO substrate, thereby effectively preventing efficient charge recombination at the interfaces of the ETL/CQDs. Furthermore, the ZTO interlayer possesses superior electron mobility, a higher visible light transmission, and a suitable energy band structure compared to STO and TO. These characteristics are advantageous for extracting charge carriers and facilitating electron transport. The PbS CQDs solar cell based on the ITO/ZnO/ZTO/PbS-FABr/PbS-EDT/NiO/Au device configuration exhibits the highest efficiency of 15.28%, which is significantly superior than the ITO/ZnO/PbS-FABr/PbS-EDT/NiO/Au solar cell device (PCE = 14.38%). This study is anticipated to offer a practical approach to develop ultrathin and compact ETL for highly efficient CQDSCs., (© 2024 Wiley‐VCH GmbH.)

Lithium-ion (Li-ion) batteries have increasingly been used in diverse applications. Accurate estimation of the state of health (SOH) of the Li-ion batteries is vital for all stakeholders and critical in various applications such as electric vehicles (EVs). The electrical equivalent circuit (EEC) 2-RC model is often used to model the battery operation but has not been used to capture the degradation of battery cells over time. This paper uses the 2-RC model to capture the degradation of the Li-ion battery. The proposed model is not only time-dependent but also captures the effect of temperature on battery degradation. The proposed approach estimates the SOH accurately and is also considerably flexible for diverse cells of different chemistry. We further generalize an N-RC model approach to evaluate the SOH of the battery. We compare the proposed model (2-RC) with the 1-RC model, and through numerical results, we show that the 2-RC model outperforms 1-RC and reduces the computational cost significantly. Similarly, the 2-RC model outperforms 3-RC and higher-order circuits. We also show that the proposed approach can capture the battery dynamics better for specific smaller orders of the polynomial (associated with Arrhenius equation) when compared with the 1-RC approach with considerably reduced (up to 60%) root mean square error (RMSE). Lastly, the average testing RMSE for 2-RC is 52.4%.

Battery Open Circuit Voltage (OCV) is of fundamental characteristic for enabling battery modeling and states estimation. However, the traditional OCV measurement method takes a very long time to make the battery reaches its equilibrium, which is rather inconvenient and cannot be performed online for battery energy storage application. Motived by this, this paper proposes an effective method for fast OCV estimation in the relaxation process. In this work, a novel relaxation model is designed for capturing the voltage response of a battery during relaxation time and the Genetic Algorithm (GA) is further applied for optimizing the model parameters and acquiring accurate OCV estimation results. Experimental results confirm the validity of the proposed method under different State of Charges (SOCs), current rates, ambient temperatures, and aging conditions. The results suggest that the proposed method can accurately and quickly estimate battery OCV, which only takes 10 minutes of measurement data (more than 2 hours for the traditional method) and the maximum estimation error is limited to merely 1.8 mV.

Anaerobic digestion (AD) can produce renewable energy and reduce carbon emissions, but the energy conversion efficiency is still limited in some waste streams. This study tested the effect of applied voltage removal for microbial electrolysis cells (MECs) treating primary sewage sludge. Two MECs were operated in parallel: a MEC-0.3 V with an applied voltage of 0.3 V and a MEC-OCV with open circuit voltage. Both reactors were inoculated with seed sludge originating from a MEC at 0.3 V applied voltage, and three batch cycles were operated for 36 d. The methane production of the MEC-OCV was 3759 mL/L in the first cycle and 2759 mL/L in the second cycle, which was similar (105% and 103%, respectively) to that of the MEC-0.3 V. However, in the third cycle, the methane production of the MEC-OCV (1762 mL/L) was 38.8% lower than that of the MEC-0.3 V (4545 mL/L). The methane contents in the biogas were 68.6–74.2% from the MEC-OCV, comparable to those from the MEC-0.3 V (66.6–71.1%). These results indicate that not only the MEC-0.3V but also the MEC-OCV outperformed AD in terms of methane yield and productivity, and the promotion using MEC-derived inoculum persisted equally with the MEC-OCV for two batch cycles after removing the applied voltage. Therefore, a MEC operation with cycled power supply may be beneficial in reducing the electric energy usage and improving the biogas production performance, compared to conventional AD. [ABSTRACT FROM AUTHOR]

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State of Charge (SOC) is the ratio of current versus total capacity of the battery. In the context of Battery Management System (BMS), the SOC is estimated by using a battery model. In this research, three battery models were presented, including (1) Thevenin battery model, (2) modified Thevenin battery model, and (3) simple battery model. Then, the SOC of those battery models was estimated using Coulomb Counting, Open Circuit Voltage (OCV), and Kalman Filter method. The simulation evaluated the performance of the SOC estimation methods, including the correctability of SOC initialization error. The simulation results showed that the proposed battery models could accurately estimate SOC. In terms of SOC initialization error, the Coulomb Counting, OCV Model 1, and OCV Model 2 could not correct the initialization error of SOC. However, the application of OCV Model 3 and Kalman Filter could provide an accurate SOC estimation with excellent correction of SOC initialization error. Compared to OCV model 3, the error correction in the Kalman Filter method was performed 25 minutes faster. Therefore, this finding suggests that Kalman Filter is the most suitable estimation method for BMS due to the high accuracy of SOC estimation (RMSE = 0.0014) and fast correction of SOC initialization error (time < 20 seconds). [ABSTRACT FROM AUTHOR]

Summary: To address the growing demand for competent photovoltaic materials, the electronic structure, and optoelectronic properties of eight molecules X1 (thieno[3,2‐b]thiophene), X2 (5,5′‐bithiazole), X3 (2,2′‐bithiophene), X4 (furan), X5 (1H‐pyrrole), X6 (furo[3,2‐b]furan), X7 (5‐(1H‐imidazol‐5‐yl)oxazole), X8 (3H,3′H‐4,4′‐biimidazole) designed via π‐spacer modification were investigated by extensive density functional theory (DFT) based calculations. The calculated HOMO‐LUMO energy (Eg) values of these designed molecules are less than alkoxy‐substituted benzothiadiazole and a rhodamine end group reference (R, Eg = 2.55 eV), whereas X8 shows the lowest (Eg = 2.17 eV) suggesting a greater charge transfer rate upon blending with donor polymer PTB7‐Th. The values of open‐circuit voltages for designed molecules are 2.30, 2.52, 2.23, 2.52, 2.37, 2.19, 2.53, and 2.18 V for X1‐X8, respectively, where X3, X6, and X8 shown lower voltages than the reference R (2.30 V). Similarly, the 0.13 eV difference of reorganization energy value of X1 compared to reference R, demonstrates higher charge transfer by X1 due to its lower hole mobility. The findings suggest potentially superior performance of organic solar cells (OSCs) fabricated with the designed molecules (X1‐X8). [ABSTRACT FROM AUTHOR]