Energy Storage最新文献

The primary purpose of this research is to analyze and evaluate the effects of various discharge rates and cell configurations on the electrochemical and thermal behavior of a Li-ion battery pack that is exposed to ambient air throughout the discharge process. The three-dimensional numerical model is designed to accomplish this purpose and discusses two different cases. While the discharge rate is changed from 0.5 C to 2 C (stepping by 0.5 C) for each cell configuration considered in the first case, the numerical solutions are obtained for the various cell configurations (6S4P and 8S3P) by keeping the discharge rate constant at 1 C. The results obtained from these solutions show that the discharge rate affects a considerable amount of the battery performances and discharge times of the battery packs, activation, and ohmic losses occurring inside each battery cell. Moreover, 6S4P discharges over a longer period (about 25%) than 8S3P. While both activation and ohmic losses decrease with the increase of discharge rate, these losses remain almost constant at 0.5 C discharge rate in all analyzed conditions. As a result, having a battery pack with a long discharge time while maintaining low temperatures is useful and desired. With this in mind, while evaluating battery packs, the 6S4P battery pack looks to have the best arrangement.

Microgrids are a viable substitute for traditional power systems because they may deliver cleaner, more dependable, affordable power with fewer losses. However, the microgrid's performance is impacted by the variable nature of renewable energy sources. Battery storage is a crucial component of microgrid planning since it defines the system's techno-economic feasibility. A standalone rural microgrid is designed in the current study, employing three distinct battery types: lithium-ion, lead acid, and zinc-bromine flow. The suggested microgrid's techno-economic analysis employs three distinct dispatch mechanisms, that is, cycle charging, load flow, and complete dispatch. The case study of the suggested framework is carried out in Lucknow (India). The system comprises PV/battery/wind energy system/diesel and battery. The simulation results suggest that the optimal system with the least electrification cost is 0.113 $/kWh using complete dispatch strategies and a zinc-bromine battery. It has 206 kWh zinc-bromine flow batteries, a 10 kW converter, a 20 kW PV, a 13-kW diesel generator, and a Combined dispatch strategy. The system's net present cost per unit cost of energy is $40 275 and 0.113 $/kWh for the chosen region, respectively. Compared to the other two battery technologies for hybrid systems, the zinc-bromine flow battery technology is also shown to be the most environmentally friendly. Among the three battery technologies available, zinc-bromine flow is best used in a particular location's hybridized operation.

Energy storage is a group of technologies that decrease the gap between energy supply and energy demand. Thermal energy storage (TES) reduces this gap at not only different temperatures but also at different places or power. Design criteria include the integration of the storage system into the whole application system, maximum load, and high-energy density. Since energy density is given by the material used, the selection of the storage material is key to the success of any energy storage system. In this paper, the potential of sodium chloride (NaCl) to be used in TES, both using sensible TES and latent TES, is evaluated for low-temperature applications and for high-temperature ones. This material is found to have high potential for successful applications, both in buildings and in industry.

This work offers a fuel cell power system with the ability to distribute power to the load from the electrical source and charge an auxiliary battery utilizing regenerative power flows created by the load. The approach is established on a bidirectional closed-loop DC converter. A bidirectional DC–DC converter is presented as a means of achieving extremely high voltage energy storage systems (ESSs) for a DC bus or supply of electricity in power applications. This paper presents a novel dual-active-bridge (DAB) bidirectional DC–DC converter power management system for hybrid electric vehicles (HEVs). The proposed system makes it possible to charge an additional battery with regenerative power flows and distributes power from the electrical source to the load efficiently. The two main stages of the DAB converter, which are the focus of this work, are an interleaved buck/boost converter on the battery and a three-phase wye-wye series resonating converter on the DC bus. Each switch's current stress is greatly reduced by this design, which lowers transmission losses and enhances thermal performance. The interleaved buck conversion on the battery allows for lesser current stress in each switch, resulting in lower transmission loss. The increasing complexity and power of automotive embedded electronic systems have made the use of more potent power electronic converters in automobiles necessary. In recent years, many dual volt (42 V/14 V) bidirectional inverter topologies for automotive systems have been presented. However, the majority of them are either inefficient or use a huge number of transistors and magnetic devices in both parallel and series arrangements. As a result, in this study, a bidirectional high-efficiency inverter with fewer components is provided. The design, modes of operation, and performance metrics of the DAB converter are examined, emphasizing its ability to achieve zero-voltage switching (ZVS) and zero current switching (ZCS) throughout its operating range. The suggested system seeks to maximize EV power management, guaranteeing high dependability and efficiency. To test all of the aforementioned qualities, an evaluation version was created, with an average efficiency of 97.5%. This research could have a substantial impact on the advancement of power electronic converters for automotive applications, leading to better EV power management, increased system reliability, and increased overall efficiency.

Heusler alloys (HAs) are a well-known family of compounds generating promising interest due to their robust structure, ease of tailoring their unique properties, and potential applications. The investigations in the direction of the electrochemical performance of these materials as electrodes for rechargeable lithium-ion batteries (LIBs) have been established theoretically and experimentally. Alloying of alkali metal ions into half-HAs unit cells can be another route to improve LIBs performance. This work presents our investigations on thermodynamically stable half-HAs CoMnZ (Z: Sb/Sn) as electrode materials for rechargeable LIBs using the first-principle calculations based on the density functional theory. The negative formation energies validate the thermodynamic stability of the alloys considered in this study. With increasing Li doping, a structural change from cubic to tetragonal and orthorhombic phase is observed in the host structure, and upon full lithiation (LiMnZ), a cubic structure is attained. The band structure calculations of the host structure and its lithiated phase indicate a metallic nature in these alloys. The calculations are also performed to investigate the structural stability of parent alloys and corresponding lithiated phases. We calculated a storage capacity of around 14.5 Ah/kg for 0.125 atomic fraction of Li atoms, which is increased by nearly 10 times upon full lithiation. A maximum open circuit voltage of around 9.8 V is calculated for Li_0.125Co_0.875MnSb and CoLi_0.125Mn_0.875Sb. Thus, all these remarkable results suggest that these intermetallic compounds have a strong potential as the cathode material for LIBs with a robust life and a large capacity.

A thermoelectric generator (TEG) converts thermal energy into electrical energy when temperature gradients are created across its two surfaces. Integrating the TEG with a phase change material (PCM) and radiative cooling (RC) can increase the temperature gradient across its two surfaces. In this study, a two-layer RC paint has been developed and applied to the cold side of a TEG, and its performance was compared with TEG-white paint and TEG-no paint. The RC lowers the temperature of the cold side by 3.5°C and 4.7°C compared to TEGs with white paint and no paint, respectively. Integrating PCM with TEG–RC ensured a high electrical output, enabling continuous power for a typical weather sensor. The PCM–TEG–RC generated 2.7and 0.61 mW during summer and winter days in Istanbul, and nighttime outputs of 0.302 W and 0.395 mW, respectively. Despite similar costs, the electrical performance of TEG–RC was nearly double that of the TEG-white paint. It has also been determined that a storage capacitor with a value of 0.5 F can provide 24-h power backup to the typical weather sensor.

Phase change materials (PCMs) have been incorporated into textiles to provide thermoregulation and temperature buffering effects on the human body. From this point of view, the aim of this study was to develop the phase change material (PCM) incorporated into the yarns for the production of textiles with a thermo-regulating function. In the study, two types of capsules poly(methyl methacrylate-co-methacrylic acid) (P(MMA-co-MAA)) walled and 1-tetradecanol core, and gelatin-gum Arabic walled and n-octadecane core were synthesized and applied to cotton textile fibers using an alternative application method developed by the authors. PCM dispersion with 6% concentration was incorporated into cotton ring spun yarns at 62.5 and 80 mL/h feeding rates. Morphological and thermal properties of the capsules and spun yarns were investigated. Thermoregulation properties of fabricated yarns were detailed evaluated by segmenting thermal history (T-history) curves into four phases and logarithmic and linear trendlines were applied to the temperature change data for unloaded and PCM incorporated yarns. Data including temperature range (°C), R² (coefficient of determination or regression factor), rate coefficient (a) and duration of phase (s) were analyzed for both capsule types and feeding rate values. The results indicated that PCM capsules with ideal spherical morphology and enough energy storage capacity were successfully applied into the cotton fibers. All cotton yarns with PCM additives exhibited lower surface temperature values greater than 2°C which is considered sufficient for the thermoregulation effect although with some distinct variations in their temperature profiles and rate coefficients. Compared to untreated cotton ring spun yarn, the temperature difference for 1-tetradecanol core@P(MMA-co-MAA) walled capsules was found to be around 4.29°C–4.56°C, whereas it was around 8.2°C–9°C for n-octadecane core@gelatin-gum Arabic walled capsules. With respect to all the results, obtained novel heat storage cotton yarn is a promising material for thermal energy storage and desirable thermal comfort applications.

The prevention of uncontrollable growth of zinc dendrites on the zinc electrodes is one of the key challenges, hindering the widespread commercialization of zinc-based energy storage technologies. Herein, we report a facile method to mitigate dendrite growth on a copper surface by an initial in situ coating of a Cu–Zn alloy layer, before zinc deposition. During further zinc deposition, the initially formed Cu–Zn alloy layer provides uniform nucleating sites and promotes homogeneous zinc deposition. A symmetrical cell, assembled using a Cu–Zn/Cu electrode could be stably cycled for over 1000 cycles in ZnSO₄ solution, at a current density of 30 mA/cm² and a coulombic efficiency of 99.9%. A zinc–air cell, assembled using Zn@Cu–Zn/Cu as the anode and rGO/Co₃O₄ composite as the cathode, exhibited a very stable performance at a high current density of 50 mA/cm² and coulombic efficiency of ~93%, for over 400 cycles. After cycling experiments, the X-ray photoelectron spectroscopy and the X-ray diffraction analysis confirmed the formation of the Cu–Zn alloy layer. Hence, the present method provides an easy route for fabricating a dendrite-free zinc electrode, for a wide range of zinc anode-based batteries.

In this paper, quasi-solid electrolytes (QSEs) “PEO + xwt.% BMIMPF₆” for x = 0–20 were prepared by the immobilization of ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF₆) to the PEO polymer matrix by solution casting technique. These quasi-solid electrolytes (QSEs) are in the thin film form of good mechanical integrity. The QSEs are characterized by X-ray diffraction (XRD), Attenuated total reflectance Infrared (ATR-IR) spectroscopy, differential scanning calorimetry (DSC)/thermogravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), impedance spectroscopy, and electrochemical techniques. XRD/DSC results confirm an increase in the flexibility (and hence polymer chain mobility) with the increasing amount of IL in the QSEs, as confirmed by the analysis of degree of crystallinity (X_c). The maximum room temperature ionic conductivity ~1.32 × 10⁻⁵ S. cm⁻¹ is obtained for the 20 wt.% IL (BMIMPF₆) added QSEs. The interaction/complexation between the dopant IL-cation BMIM⁺ with the ether oxygen (i.e., COC bond of PEO) has been confirmed by FTIR spectroscopic analysis. FESEM results confirm the appearance of crystalline spherical grains (spherulites), whose size decreases with the increasing amount of IL in the membranes and shows overall semicrystalline microstructures. The TGA analysis confirmed that the onset decomposition temperature of the QSEs is found to be ~175°C, which is the sufficient temperature range of operation for the solid-state electrochemical devices. The electrochemical performances of the QSEs were examined by fabricating the symmetrical electrical double-layer capacitor (EDLC) device. The fabricated EDLC cell with optimized QSE “PEO + 20 wt.% BMIMPF₆” with biomass-based honeycomb activated carbon (HCAC) electrodes offers specific energy ~5.8 Wh kg⁻¹ at power density ~ 79.9 W kg⁻¹. It also displays excellent cycling stability with 81.3% of the initial specific capacitance after 2500 charge–discharge cycles.

Accurate estimation of state of health (SoH) of the battery over long-term is a critical challenge for the battery management systems in electric vehicles. This is due to the challenges in accurately modeling the accelerated aging and degradation phenomena caused by diverse operating conditions of the battery. This paper presents a cascaded recurrent neural networks (RNN) with long short-term memory (LSTM) to estimate the internal resistance and SoH, taking account of various abnormal operating conditions of the battery. A datasheet-based degradation model of the battery is developed using fade equations. The training and validation data set for LSTM-RNN are generated by subjecting the battery model to various factors that cause accelerated degradation, such as fast charging, varying operating temperatures, overutilization, and cell imbalance. The cascaded LSTM-RNN is trained to estimate SoH only once after the completion of every charge–discharge cycle. The training error index parameters of the proposed SoH estimator are well within 1%, demonstrating the reliability and robustness of the estimator to diverse operating conditions of the battery.