batterydata/paper-abstracts huggingface dataset:
The BMW Group has launched two micro-hybrid functions in high volume models in order to contribute to reduction of fuel consumption in modern passenger cars. Both the brake energy regeneration (BER) and the auto-start-stop function (ASSF) are based on the conventional 14V vehicle electrical system and current series components with only little modifications. An intelligent control algorithm of the alternator enables recuperative charging in braking and coasting phases, known as BER. By switching off the internal combustion engine at a vehicle standstill the idling fuel consumption is effectively reduced by ASSF. By reason of economy and package a lead–acid battery is used as electrochemical energy storage device. The BMW Group assembles valve-regulated lead–acid (VRLA) batteries in absorbent glass mat (AGM) technology in the micro-hybrid electrical power system since special challenges arise for the batteries. By field data analysis a lower average state-of-charge (SOC) due to partial state-of-charge (PSOC) operation and a higher cycling rate due to BER and ASSF are confirmed in this article. Similar to a design of experiment (DOE) like method we present a long-term lab investigation. Two types of 90Ah VRLA AGM batteries are operated with a test bench profile that simulates the micro-hybrid vehicle electrical system under varying conditions. The main attention of this lab testing is focused on capacity loss and charge acceptance over cycle life. These effects are put into context with periodically refresh charging the batteries in order to prevent accelerated battery aging due to hard sulfation. We demonstrate the positive effect of refresh chargings concerning preservation of battery charge acceptance. Furthermore, we observe moderate capacity loss over 90 full cycles both at 25°C and at 3°C battery temperature.
Environmentally friendly energy sources with high power quality or reliability and low costs are regarded as an effective solution for energy supply problems arising from use of conventional methods. Presented in this paper, gives an optimal management strategy of PV/wind/diesel independent hybrid systems for supplying required energy in autonomous microgrids. A new optimization problem is formulated for minimizing the capital investment and fuel costs of the system. To solve the proposed optimization problem a novel algorithm, named Guaranteed convergence Particle Swarm Optimization with Gaussian Mutation (GPSO-GM), is developed. Two operators, namely mutation and guaranteed convergence, are added to PSO in order to help finding more accurate results and increasing the speed of calculations. The performance of the proposed strategy is evaluated in two case studies.
Advanced flexible electrode is crucial in the development of flexible energy storage devices for emerging wearable and portable electronics. Herein, a free-standing flexible mesoporous Li4Ti5O12-rGO (LTO-rGO) nanocomposite film is rationally designed and fabricated for lithium ion batteries (LIBs). This efficient synthesis involves the growth of lithium titanate hydrate (LTH) precursors on the graphene oxide (GO) by a hydrothermal reaction, assembly into LTH-GO film by vacuum filtration with some extra GO added, and subsequent conversion into LTO-rGO nanocomposite film through calcination. When rGO content in the LTO-rGO film is set, the addition sequence of GO is found to affect its textural and mechanical properties. The resultant free-standing LTO-rGO electrode, taking advantages of high Li4Ti5O12 loading of 73.9%, mesoporous layer-stacked channels with good electron/ion conductivity, good mechanical strength, and enlarged electrode/electrolyte contact area, delivers excellent electrochemical performance (e.g., specific capacity of 135.4 mAh g−1 at 40 C) over the electrode of conventional configuration. Moreover, no organic but all inorganic reagents are used in the synthesis, offering an eco-friendly, cost-efficient, and easily scalable way to fabricate binder-free flexible electrode for LIBs.
Na3V2(PO4)3 (NVP) is an extensively researched cathode material for the sodium-ion batteries (NIBs). Size reduction and nanocarbon coating are often used to improve its rate performance. These are strategies that have been proven highly effective for LiFePO4 (LFP), a phosphate-based cathode material which is nowadays popular with the lithium-ion batteries. Nanocarbon coating is undoubtedly useful since NVP encounters similar external electron transport barriers as LFP. The effect of size reduction, however, remains debatable since in theory, the 3D NASICON framework of NVP is more efficient for solid state ionic diffusion than is LFP. We have undertaken the measurements of the electrochemical performance of NVP particles of different sizes, electrode compositions, active material loadings and processing conditions, for the purpose of identifying the most significant factors which determine the rate performance of NVP as a NIB cathode material.
Nowadays, the deterioration of ecological environment and the ever rising gas price make green transportation our relentless pursuit. Energy-saving, low-emission even zero-emission electric vehicles (EVs) have been considered as one solution to the problem. With the rapid development of plug-in electric vehicle (PHEV) and forceful support and incentives from the government, PHEV and its supporting facilities are being gradually popularized. When randomly being connected to the power grid in large scale, PHEVs will bring new challenges to power grid in operation and management. This paper presents an overall review on historical research on power system integrated with electric vehicles and especially focuses on economic dispatch of PHEV in the electricity market. The paper also discusses the joint scheduling problem considering other renewable energy resources and risk management of PHEV-penetrated power systems.
In-situ neutron powder diffraction was employed to investigate the structural evolution of the electrode materials in a commercial lithium-ion battery used for electric buses in Taiwan. The battery, containing a vanadium-added LiFePO4 cathode, does not exhibit a delayed phase transition between LiFePO4 (triphylite) and FePO4 (heterosite) suggesting that the delayed phase transition can be suppressed through the use of vanadium-added LiFePO4 cathodes, which also enhances the capacity and prolongs the cycle life of these batteries. Furthermore, we characterize the readily reversible structural change of the anode (Li x C6 where 0 < x ≦ 1) and correlate this to battery voltage.
Using excellent kinetic transport graphitized carbon nanofibers network to construct free-standing V2O5-based electrode is an effective approach to develop high-performance lithium ion batteries. Herein, we successfully prepare graphitized carbon nanofibers by combining the electrospinning and the catalytic effect of iron oxide, and the conductance of graphitized carbon nanofibers is increased by 5 × 10 4 times compared to the amorphous carbon. Through hydrothermal method, the V2O5 nanosheets can be anchored on the surface of graphitized carbon nanofibers, forming a flexible and free-standing composite electrode, which can be directly used as cathode electrodes with a reversible capacity of 290 mAh g−1 at 0.1 C and a capacity higher than 105 mAh g−1 even at a large current density of 20 C, retaining a capacity of 160 mAh g−1 at 5.0 C even over 700 cycles. This is the first report to synthesize V2O5 nanosheets on graphitized carbon nanofibers prepared by electrospinning to construct a free-standing composite electrode with high rate capability and cycling stability lithium ion storage performances.
Intensive research efforts are underway to enable applications of layered lithium transition metal oxides in batteries. Here the authors report an oxidative chemical vapour deposition technique to conformally coat both the primary and the secondary particles of these oxides to unleash potential applications.
In most cases, batteries consist of multiple cells with different interconnections in which the weakest cells determine the usable capacity, performance and lifetime. Since data on initial production-related cell to cell parameter variance is well known, only little data on variance change over lifetime is available. This work investigates how variance spreads with age. Twenty differently aged electric bike (pedelec) batteries are disassembled and the state of health, as well as the internal resistance, are measured cell by cell for each of these batteries. The results show the development of cell to cell variation of aged batteries. Gathered data is also used to calculate capacity limitations through progressed variation. The methodology of the investigation can be used to analyse potential use cases for active balancing systems.
The preparation of methylene ethylene carbonate (MEC) and the incorporation of MEC into lithium ion batteries as an electrolyte additive were investigated. MEC is prepared in good yield by mercury catalyzed cyclization. Addition of low concentrations of MEC (1–2%) to 1M LiPF6 in 3:7 ethylene carbonate/ethyl methyl carbonate improves the capacity retention of lithium ion batteries cycled at elevated temperature (60°C). Ex situ surface analysis (XPS and FTIR) of the electrodes supports the presence of poly(methylene ethylene carbonate) on the anode surface. Modification of the anode solid electrolyte interphase (SEI) correlates with significant improvements in the cycling performance at 60°C.
Sn-based oxide materials as an anode of lithium ion batteries (LIBs) suffer from the unavoidable mechanical stress originated from huge volume changes during lithiation/delithiation reactions. We synthesized the hierarchical SnO nanobranches (NBs) decorated with Sn nanoparticles on Cu current collector using a vapor transport method. The Sn-decorated SnO NBs as an anode of LIB showed good electrochemical performance with high reversible capacity retention of as high as 502 mAh/g and rate capability of 455 mAh/g at a current density of 2.0 A/g after 50 cycles. Through the morphological and crystal structure analyses after the charge and discharge processes, it was found that the morphology of Sn-decorated SnO NBs was transformed to nanoporous layered-structure, composed of Sn and lithium oxide, during the repeated lithiation/delithiation reactions. The free-volume of Sn-decorated SnO NBs and nanoporous layered-structure effectively accommodate the huge volume changes and enhance the electrochemical cyclability by facilitating the diffusion of Li-ions.
Conversion-type reaction anode materials with high specific capacity are attractive candidates to improve lithium ion batteries (LIBs), yet the rapid capacity fading and poor rate capability caused by drastic volume change and low electronic conductivity greatly hinder their practical applications. To circumvent these issues, the successful design of yolk@shell Fe2O3@C hybrid composed of a columnar-like Fe2O3 core within a hollow cavity completely surrounded by a thin, self-supported carbon (C) shell is presented as an anode for high-performance LIBs. This yolk@shell structure allows each Fe2O3 core to swell upon lithiation without deforming the carbon shell. This preserves the structural and electrical integrity against pulverization, as revealed by in situ transmission electron microscopy (TEM) measurement. Benefiting from these structural advantages, the resulting electrode exhibits a high reversible capacity (1013 mAh g−1 after 80 cycles at 0.2 A g−1), outstanding rate capability (710 mAh g−1 at 8 A g−1) and superior cycling stability (800 mAh g−1 after 300 cycles at 4 A g−1). A Li-ion full cell using prelithiated yolk@shell Fe2O3@C hybrid as the anode and commercial LiCoO2 (LCO) as the cathode demonstrates impressive cycling stability with a capacity retention of 84.5% after 100 cycles at 1 C rate, holding great promise for future practical applications.
Much research has been devoted to improving the water splitting efficiency of hematite photoanodes. In this study, we demonstrate a significant advance in the colloidal nanocrystal deposition (CND) process to obtain hematite thin films with high photoelectrochemical performance. For this approach, we designed the magnetic field-assisted dip coating process to achieve homogeneous hematite thin films by using magnetic nanocrystals (maghemite) as the precursor. Using this non-aqueous deposition route, we produced undoped and Sn-doped hematite photoanodes with excellent photocurrents of 1.4 mA cm−2 at 1.23 VRHE and 2.7 mA cm−2 at 1.23 VRHE, respectively, using a standard AM1.5 G solar light simulator.
Redox flow batteries offer a potential solution to an increase in renewable energy generation on the grid by offering long-term, large-scale storage and regulation of power. However, they are currently underutilised due to cost and performance issues, many of which are linked to the microstructure of the porous carbon electrodes used. Here, for the first time, we offer a detailed study of the in situ effects of compression on a commercially available carbon felt electrode. Visualisation of electrode structure using X-ray computed tomography shows the non-linear way that these materials compress and various metrics are used to elucidate the changes in porosity, pore size distribution and tortuosity factor under compressions from 0%–90%.
This article provides an overview of current findings on Theory of Mind (ToM) in human children and adults and highlights the relationship between task specifications and their outcome in socio-cognitive research.
Low illumination (10−4 suns) and indoor light energy harvesting is needed to meet the demands of zero net energy (ZNE) building, Internet of Things (IoT), and beta-photovoltaic energy harvesting systems to power remote sensors. Photovoltaic (PV) solar cells under low intensity and narrow (±40nm) light spectrum conditions are not well characterized nor developed, especially for commercially available devices and scalable systems. PV operating characteristics under 1 sun illumination decrease at lower light intensity and narrow spectrum conditions (efficiency drops from ∼25% at 100mWopt/cm2 to 2% at 1μWopt/cm2). By choosing a PV with a bandgap that matches the light source operating wavelength, the total system efficiency can be improved. By quantifying losses on homojunction photovoltaics (thermalization and leakage current), we have determined the theoretical optimized efficiency for a set of PV material and a selected set of light sources. We measure single-junction solar cells’ parameters under three different light sources (indoor light and narrow spectrum LED sources) with light intensities ranging from 0.5 to 100μWopt/cm2. Measurements show that indium gallium phosphide (InGaP) PV has the highest surface power density and conversion efficiency (29% under ≈1μWopt/cm2 from a 523nm central peak LED). A beta-photovoltaic experimental study identifies InGaP to be optimized for use with the ZnS:Cu, Al and tritium at STP. The results have guided the selection of PV material for scalable isotope batteries and other low-light energy harvesting systems.
Layered 2D metal hydroxides and oxides with solvated ions inside their layers are well-known materials for energy storage applications. Although thin-film layered alpha-cobalt hydroxide (α-Co(OH)2) is recognized as one of the promising candidates among many other 2D materials, it still suffers from its poor stability in alkali solution i.e., 6 M KOH. In this work, the charge storage mechanism and the electrochemical performance of α-Co(OH)2 in a room-temperature ionic liquid (IL) namely 1-butyl-1-methyl-pyrrolidinium dicyanamide ionic liquid ([BMPyr+][DCA−] IL) were investigated and compared with those in 6 M KOH. Interestingly, α-Co(OH)2 in [BMPyr+][DCA−] IL maintains their capacity retention up to 95.9% after 10,000 cycles at 0.15 mA cm−2 for the half-cell evaluation. The asymmetric cell of thin-film α-Co(OH)2//reduced graphene oxide aerogel (rGOae) assembled in [BMPyr+][DCA−] IL electrolyte provides a high areal capacitance of 18.54 F cm−2 (28.6 F g−1) at 0.15 mA cm−2 as compared with other thin-film supercapacitors. The charge storage mechanism of α-Co(OH)2 in [BMPyr+][DCA−] IL investigated by in situ X-ray absorption spectroscopy (XAS) and ex situ X-ray photoelectron spectroscopy (XPS) confirms that [DCA−] can faradaically react with α-Co(OH)2 providing CoOOH and NH(CN)2. Understanding charge storage mechanism of 2D metal hydroxides may be useful for future development of energy storage technology.
The Matanza-Riachuelo is one of the most polluted rivers of Latin America. The complex chemical mixture of pollutants discharged into the river is accumulated in the river sediments. In this paper, Matanza-Riachuelo river sediment composition and genotoxicity were tested in order to develop a cost-effective, environmentally sound option for disposal and management of contaminated dredged materials. Sampling was performed in a rural area, in a solid waste dumpsite and also in an urban and industrial area. The concentrations of total heavy metals increased from the upper basin to the lower basin. The Ames Salmonella typhimurium test and the Saccharomyces cerevisiae D7 test were performed using toxicity characteristic leachate procedure (TCLP) leachates. The concentrations of copper, lead, and chromium in the leachates exceeded the guide levels for the protection of aquatic life. Low concentrations of organic chlorinated compounds were detected in the leachates. Genotoxic profiles were obtained by testing TCLP leachates from polluted sediment samples with Salmonella typhimurium, Saccharomyces cerevisiae D7, and water sediment suspension with Allium cepa test. No mutagenicity effects on Ames test were observed. Gene conversion and mitotic reversion in Saccharomyces cerevisiae D7 and chromosome aberration in Allium cepa were induced by the sediment samples. Results obtained suggest that dredged sediments could be classified as genotoxic hazardous waste.
Li1+0.5x Co1−x V x (PO4)1+0.5x /C (x =0, 0.05, 0.10) composites with ordered olivine structure have been synthesized for use as cathode material in lithium ion batteries. The morphology and microstructure are characterized by scanning electron microscope, transmission electron microscopy and X-ray diffraction. The electrochemical test results show that addition of vanadium into LiCoPO4 remarkably improves its charge and discharge behavior. Li1.025Co0.95V0.05(PO4)1.025/C electrode gives its initial discharge capacity of 134.8mAhg−1 at 0.1C current rate, against 112.2mAhg−1 for the pristine LiCoPO4/C, and exhibits much better cyclic stability than the latter. In particular, vanadium doping leads to an enhancement of the discharge voltage plateau for about 70mV.
Owing to low efficiency of traditional ships and the serious environmental pollution that they cause, the use of solar energy and an energy storage system (ESS) in a ship’s power system is increasingly attracting attention. However, the swinging of a ship raises crucial challenges in designing an optimal system for a large oil tanker ship, which are associated with uncertainties in solar energy. In this study, a series of experiments are performed to investigate the characteristics of a photovoltaic (PV) system on a moving ship. Based on the experimental results, an interval uncertainty model of on-board PV generation is established, which considers the effect of the swinging of the ship. Due to the power balance equations, the outputs of the diesel generator and the ESS on a large oil tanker are also modeled using interval variables. An interval optimization method is developed to determine the optimal size of the ESS in this hybrid ship power system to reduce the fuel cost, capital cost of the ESS, and emissions of greenhouse gases. Variations of the ship load are analyzed using a new method, taking five operating conditions into account. Several cases are compared in detail to demonstrate the effectiveness of the proposed algorithm.
Demand-side management programs such as load shifting utilise the flexibility in the load consumption pattern of consumers to enable the effective capacity utilisation of renewable energy sources. The locational and temporal characteristics of renewable energy sources cause forecasting and operational challenges in the implementation of such a renewable energy program. In this paper, a dynamic load-shifting program using real-time data in a cloud computing framework is proposed to address the aforementioned issues. A new dynamic renewable factor is proposed to facilitate on-time incentive based load shifting program. The effectiveness of the dynamic load-shifting program was evaluated using simulated case studies. The case study indicates that PV energy utilisation at the consumer side is increased by 18% by the application of the proposed load-shifting program. The study result in Kerala, India, consisting of more than 7.5 million domestic consumers, indicates that demand reduction of 250–300MW at times of peak demand can be achieved by using load shifting in the domestic sector.
A facile aerosol-based synthetic approach is demonstrated for the fabrication of silsesquioxane-graphene oxide (rGO-SQ) and reduced graphene oxide-manganese oxide (MnOx-rGO) nanocomposites, as the materials for negative and positive electrodes in an asymmetric supercapacitor (ASC), respectively. Microwave-assisted hydrothermal treatment is employed to form reduced graphene oxide (AS-rGO). Fourier-transformed infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and x-ray photoelectron spectrometry are used to provide complementary material characterizations for the synthesized nanocomposites. The results show that the composition and the morphology of the synthesized materials are tunable by the adjustment of precursor concentration and annealing temperature. From the shapes of cyclic voltammetric and galvanostatic charge-discharge curves, the conductivity and the subsequent capacitive performance of MnOx are enhanced effectively by the hybridization with rGO. The highest double-layer capacitance of AS-rGO is 118 F g−1, and the highest specific capacitance of MnOx-rGO reaches 183 F g−1 under a scan rate of 5 mV s−1. The ASC assembled with AS-rGO and MnOx-rGO possessed high charge-discharge reversibility at a cell voltage of 2.0 V. A high operation stability of ASC can be achieved, as evidenced by the high retention (98% of the retention) in the 10,000-cycle charge-discharge test at a current density of 2 A g−1. The maximum specific energy and specific power of the ASC respectively reach 16.6 Wh kg−1 and 1.052 kW kg−1 at a current density of 1 A g−1. This study demonstrates a prototype approach for the fabrication of nanocomposite electrode materials by design with the ability of scalable mass production.
The aim of this paper is to present a sequential quadratic programming (SQP) based equivalent consumption minimum strategy (ECMS) (SECMS) for fuel cell hybrid electric vehicle (FCHEV) powered by fuel cell, battery and supercapacitor. In order to decrease hydrogen consumption and increase the durability of power sources, fuel cell is chosen as the main power source and supplies steady current, battery is designed as the main energy buffer and the replacement of fuel cell failure and supercapacitor is operated to supply peak power. Low energy density of supercpacitor lets its equivalent hydrogen consumption be taken as zero for many ECMS researches. This simplification leads to suboptimal fuel economy and complex of control system. SECMS considers hydrogen consumption of three power sources into objective function to solve this problem. A rule based control strategy (RBCS) and an hybrid ECMS operating mode control strategy (OMCS) (HEOS) are also designed to compare with SECMS. An experimental test bench is built to validate the comparative study of three strategies. The results show that compared with RBCS and HEOS, hydrogen consumption of SECMS decreases of 2.16 % and 1,47 % respectively and it also has the most smooth fuel cell current, which means a lowest fuel cell degradation.