batterydata/paper-abstracts huggingface dataset:
Battery-management systems rely on mathematical sets of equations known as models when implementing battery controls procedures. Models are used in state-of-charge, state-of-health, available-energy, and available-power estimation tasks. These models should be high fidelity for good estimates but also computationally lightweight for inexpensive implementation. This paper and its Part-2 companion concern themselves with simple but accurate models of lithium-ion cells having composite electrodes, which are composed of a blend of multiple active materials. In this paper, we develop two forms of equivalent-circuit model (ECM): the series ECM and the parallel ECM—and show how to find values for the model parameters using current–voltage input–output data. We compare simulations of the ECMs to truth data from simulations of a full-order model and show that an ECM designed with knowledge of the material blend can outperform a standard ECM of similar complexity. In the companion paper, we show that it is further possible to create physics-based reduced-order models that have greater predictive power.
Cell replacement has the potential to become a frontline therapy to remedy behavioral impairments in Huntington’s disease. To determine the efficacy of stem cell transplantation, behavioral assessment and in vivo monitoring of the lesion environment are paramount. We here demonstrate that neural stem cells from the MHP36 cell line prevented the development of a deficit on the beam walk test while providing partial recovery of learning in the water maze. However, no beneficial effect on rats’ impairment in the staircase test was observed. By quantification of the lesion from serial magnetic resonance images, no effect of neural stem cells on lesion volume was observed. Instead, a preservation of striatal volume over time and its correlation with performance on the beam walk test suggested that sparing of behavioral function was associated with a stagnation of ongoing tissue loss rather than a reduction in lesion size. Serial imaging therefore warrants further implementation in clinical trials of neural grafts to monitor in vivo changes in the damaged brain due to transplantation.
A transient one-dimensional mathematical model is developed and used to study the performance and thermal behavior of the silver–zinc cell during discharge. The model considers the negative (zinc) electrode, separator, and positive (silver) electrode and describes the simultaneous electrochemical reactions in the positive electrode, mass transfer limitations, and heat generation. Changes in porosity and electrolyte composition due to electrochemical reactions, local reaction rates, diffusion, and migration of electrolyte are reported. Emphasis is placed on understanding the movement of the reaction front in the negative electrode during discharge and its correlation to the useful capacity of the cell. The sensitivity of this capacity to changes in the values of initial electrolyte, exchange current densities, and tortuosity are presented. It is shown that under certain conditions, in a system employing 25% KOH as the electrolyte, the useful capacity of the cell could be limited to 55.6% of its rated capacity when the discharge rate is increased from 1C to 2C. The temperature rise in a single cell was predicted and observed to agree with the experimental values.
Oxygen reduction reaction (ORR) is of crucial importance in fuel cells and metal–air batteries, however, the sluggish dynamics of ORR remains a critical issue to be addressed. Here, we report the preparation of hexagonal spinel-type Mn2AlO4 nanosheets with a high BET surface area of up to 164m2 g−1 through a dealloying–annealing strategy. The Mn2AlO4 catalyst shows a good catalytic activity towards ORR in the alkaline solution, as well as much better methanol tolerance than the commercial Pt/C. Moreover, both the electrochemical measurements and density functional theory (DFT) calculations (adsorption energy, density of states, H2O2 decomposition) demonstrate that the ORR on Mn2AlO4 is a four-electron pathway. In addition, the DFT results expound the reason why the Mn2AlO4 catalyst has much better methanol tolerance than Pt/C.
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.
Starting from published charge/discharge curves and X-ray data on Pmmn-LiFeO2 and LiFe5O8 as cathode materials vs. Li anode, a scheme of electrochemical reactions is proposed to explain the unclear electrode functionality of the ‘corrugated layer’ LiFeO2 phase. The scheme was validated by quantum-mechanical calculations (CRYSTAL09 code, hybrid B3LYP Hamiltonian) on a number of structural models for Li1−x FeO2, LiFe5O8, and Li3Fe5O8. Magnetic interactions were taken into account, finding antiferromagnetic (Li1−x FeO2) and ferrimagnetic (LiFe5O8 and Li3Fe5O8) orderings as stable states. At variance with spinel-like LiFe5O8, Li3Fe5O8 displays a rocksalt-type superstructure. The computed energies for reactions (I) 4LiFeO2 →4Li0.75FeO2 +Li, (II) 4Li0.75FeO2 +Li→4/5LiFe5O8 +8/5Li2O, and (III) 1/2LiFe5O8 +Li↔1/2Li3Fe5O8 are 4.44, −3.62, and −2.10eV, respectively. Such values compare satisfactorily with the average charge/discharge voltages observed for positive electrodes made up of Pmmn-LiFeO2 and of LiFe5O8.
In this work, porous carbon materials were prepared from styrene–acrylonitrile (SAN) carbon precursors. These precursors were chemically activated with KOH; activation was carried out at different temperatures to investigate the effect of thermal treatment on the surface and electrochemical properties of the activated materials (A-SAN). Furthermore, nitrogen was doped into the A-SAN materials to evaluate the influence of nitrogen functional groups on electrochemical properties. A-SAN 700 was found to have the highest specific capacitance; it is likely that the extensive microporous structure of this material contributes to its considerable specific capacitance. Nitrogen doping at temperatures above 700°C yields lower-quality materials, which is thought to be due to deformation of micropore structures.
Rapid advancement of information and communication technologies enables to produce more mobile devices. Most of distance education students need access to study materials, communications tools and further learning means not only at home and in their working place, but for example on business trips. The aim of this paper is to present possibilities of mobile technology in teaching informatics and programming. According to the results of surveys carried out in primary, secondary schools and universities. We can say that mobile devices are increasingly used in learning. Results of surveys and experiments show that mobile devices can enhance the teaching of Computer Science, Programming and Algorithms. The paper describes the experience of teaching and the development of mobile applications, applications for teaching and for users with special needs.
The rising awareness of decreasing natural resources has brought forward the idea of a circular economy and resource efficiency in Europe. As a part of this movement, European countries have identified the need to monitor residual waste flows in order to make recycling more efficient. In Finland, studies on the composition of residual household waste have mostly been conducted using different methods, which makes the comparison of the results difficult. The aim of this study was to develop a reliable method for residual household waste composition studies. First, a literature review on European study methods was performed. Also, 19 Finnish waste composition studies were compared in order to identify the shortcomings of the current Finnish residual household waste composition data. Moreover, the information needs of different waste management authorities concerning residual household waste were studied through a survey and personal interviews. Stratification, sampling, the classification of fractions and statistical analysis were identified as the key factors in a residual household waste composition study. The area studied should be divided into non-overlapping strata in order to decrease the heterogeneity of waste and enable comparisons between different waste producers. A minimum of six subsamples, each 100kg, from each stratum should be sorted. Confidence intervals for each waste category should be determined in order to evaluate the applicability of the results. A new three-level classification system was created based on Finnish stakeholders’ information needs and compared to four other European waste composition study classifications.
Water electrolysis enables the storage of renewable electricity via the chemical bonds of hydrogen. However, proton-exchange-membrane electrolysers are impeded by the high cost and low availability of their noble-metal electrocatalysts, whereas alkaline electrolysers operate at a low power density. Here, we demonstrate that electrocatalytic reactions relevant for water splitting can be improved by employing magnetic heating of noble-metal-free catalysts. Using nickel-coated iron carbide nanoparticles, which are prone to magnetic heating under high-frequency alternating magnetic fields, the overpotential (at 20 mA cm−2) required for oxygen evolution in an alkaline water-electrolysis flow-cell was decreased by 200 mV and that for hydrogen evolution was decreased by 100 mV. This enhancement of oxygen-evolution kinetics is equivalent to a rise of the cell temperature to ~200 °C, but in practice it increased by 5 °C only. This work suggests that, in the future, water splitting near the equilibrium voltage could be possible at room temperature, which is currently beyond reach in the classic approach to water electrolysis.
Capsule endoscopy enables high-resolution depiction of small bowel mucosa and has been shown, by several studies, to have a high diagnostic yield in a variety of small bowel diseases. In this review, we critically assess the contributions of capsule endoscopy and imaging tests in common small bowel disorders. Radiological tests that only assess the small bowel mucosa will be less useful in the era of capsule endoscopy.
The open circuit voltage (OCV) is an essential variable for accurate state of charge (SoC) estimation of lithium ion batteries in electric vehicles (EVs). OCV test must be performed periodically to calibrate the OCV-SoC relationship after battery aging. Furthermore, due to pronounced hysteresis effects and wide flat regions in the OCV-SoC curves of LiFePO4 batteries, the traditional OCV tests often take three to five days to obtain data on one or more fully charge and discharge cycles, which are time-consuming and become unreliable under changing driving cycles and operating conditions. In addition, the OCV-SoC relationship determined in a certain aging stage cannot be used for the full life cycle and whole operating conditions. In this paper, the OCV-SoC relationship is extracted from any existing current-voltage measurements by using an H infinity filter within several seconds, which is verified under constant current conditions and dynamic conditions. Our results show that the estimated OCV can result in accurate SoC estimation with a maximum error of 1%.
NASICON structured NaTi2(PO4)3 with stable and open framework has become a promising electrode material for sodium-ion batteries. However, the intrinsic low electronic conductivity of NaTi2(PO4)3 leads to inferior rate capability and poor active material utilization. Herein, we first report the synthesis of carbon-coated hierarchical NaTi2(PO4)3 mesoporous microflowers (NTP/C-F), via a facile and controllable solvothermal method and subsequent annealing treatment. The unique structural features endow the NTP/C-F with excellent structural stability, enhanced charge transfer kinetics, and suppressed polarization. This architecture exhibits superior sodium storage performance: high initial capacity (125mAhg−1 at 1C), outstanding rate capability (95mAhg−1 at 100C), and ultra-long cycling stability (capacity retention of 77.3% after 10,000 cycles at 20C). Time-resolved in-situ X-ray diffraction study reveals a typical two-phase electrochemical reaction with reversible structure change. This work suggests the integration of hierarchical structure and carbon coating provides a promising approach for boosting the electrochemical performances of battery electrode materials.
A compositive synthesis of gel polymer electrolytes by blending poly(propylene carbonate) (PPC) into poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) as a polymer host is proposed. The blending polymer is produced by a facile solution casting method and ester groups of PPC are successful introduced into PVDF-HFP. The gel polymer electrolyte displays an excellent ion conductivity of 1.18 × 10−3 S cm−1, broad electrochemical window up to 4.8 V (vs. Li/Li+) and outstanding electrochemical stability within rechargeable lithium batteries at room temperature. The improvement of ion conductivity is attributed to the decrease of polymer crystallizability and the increase of micro pores. The strategy of blending is promising for the modification of PVDF-HFP electrolyte and foreground application in next-generation solid energy conversion devices.
ZnMn2O4/C nanoparticles are synthesized by one step polyol assisted pyro-synthesis for use as the anode in rechargeable lithium ion batteries without any post heat treatment. The as-prepared ZnMn2O4/C is tetragonal with a spherical particle size in the range of 10–30nm. Electrochemical measurements were performed using the as-prepared powders as the active material for a lithium-ion cell. The nanoparticle electrode delivered an initial charge capacity of 666.1mAhg−1 and exhibited a capacity retention of ∼81% (539.4mAhg−1) after 50 cycles. The capacity enhancement in the as-prepared ZnMn2O4/C may be explained on the basis of the polyol medium that enables to develop a sufficient carbon network that can act as electrical conduits during electrochemical reactions. The carbon network appears to enhance the particle-connectivity and hence improve the electronic conductivities.
Layered Li[Li0.15Ni(0.275−x/2)Al x Mn(0.575−x/2)]O2 materials were synthesized via a sol–gel method at 900°C in air. Li[Li0.15Ni(0.275−x/2)Al x Mn(0.575−x/2)]O2 and Li2MnO3 phase mixed compounds were obtained. Substitution of Al3+ ions were shown to prevent the structural degradation of the electrode material allowing higher discharge capacities. The 6mol% aluminum-doped Li[Li0.15Ni0.245Al0.06Mn0.545]O2 electrode delivered approximately 210mAhg−1 discharge capacity in a cut-off range between 2.5 and 4.6V. It was found that the Al doping on Li[Li0.15Ni(0.275−x/2)Al x Mn(0.575−x/2)]O2 material could decrease the area specific impedance (ASI).
In this paper, the hybrid catalysts of manganese oxide decorated by silver nanoparticles (Ag-MnOx) are fully investigated and show the excellent oxygen reduction reaction (ORR) activity. The Ag-MnO2 is synthesized by a facile strategy of the electroless plating of silver on the manganese oxide. The catalysts are characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Then, the ORR activities of the catalysts are systematically investigated by the rotating disk electrode (RDE) and aluminum-air battery technologies. The Ag nanoparticles with the diameters at about 10nm are anchored on the surface of α-MnO2 and a strong interaction between Ag and MnO2 components in the hybrid catalyst are confirmed. The electrochemical tests show that the activity and stability of the 50%Ag-MnO2 composite catalyst (the mass ratio of Ag/MnO2 is 1:1) toward ORR are greatly enhanced comparing with single Ag or MnO2 catalyst. Moreover, the peak power density of the aluminum-air battery with 50%Ag-MnO2 can reach 204 mWcm−2.
Experimental investigations conducted on a large format lithium ion polymer battery (LiPB) have revealed that side reactions taking place at anode are the major factor for degradation of the battery performance and lead to capacity and power fade. Side reactions consume ions and solvents from the electrolyte and produce deposits that increase the thickness of the solid electrolyte interphase (SEI) layer and form a new layer between composite anode and separator. These phenomena are described using physical principles based on the Tafel and Nernst equations that are integrated into the developed electrochemical-thermal model. The key parameters for the side reactions used in the model are experimentally determined from self-discharging behavior of the battery. The integrated model is then validated against experimental data obtained from different operating conditions. Analysis has revealed that the capacity fade is predominantly caused by loss of ions and active materials. The results also show that the rate of side reactions and degradations are more severe at charging process under high SOC and high C-rate due to low overpotential of the side reactions.
The changes of Li+/vacancy arrangement in Li2+x Ti3O7 with a ramsdellite-type structure upon topo-electrochemical Li+ insertion were investigated by the entropy measurement of reaction combined with the Monte Carlo simulation. The experimental entropy measurement was conducted by potentiometric and calorimetrical methods. The obtained experimental data were in good accordance with simulated results. The results indicated that the ordered Li+/vacancy arrangement appeared at the compositions of x ∼0.45 and ∼1.20, where the observed entropy of reaction humped. The ordering of Li/vacancy were also indicated at the composition x ∼0.24 and 1.16 in Li2+x Ti3O7 by the Monte Carlo simulation which considers the most stable Li/vacancy arrangement in terms of Coulombic interaction. This substantial agreement between electrochemical behaviors and computational results confirmed that the formation of superstructure arising from Li/vacancy arrangement during the electrochemical reaction deeply related to the atomic level Coulombic interactions.
Urban regeneration involves cooperation between public and private parties. Parties conclude urban development agreements (DAs) that contain the specific conditions under which they are willing to cooperate for the realisation of an urban development project. Based on a relational approach to contracting which holds that all contracts are embedded in relations, this paper presents five guiding principles for the drafting and negotiation of DAs for such projects. These guiding principles are used to analyse four urban development projects, located in Amsterdam (Zuidas), London (King’s Cross) and New York City (Battery Park City and Hudson Yards).
To determine the structure and electrochemical properties of La–Mg–Ni-based Pr5Co19-type super-stacking structure alloys, a La0.84Mg0.16Ni3.80 alloy was designed and synthesized by step-wise powder sintering. X-ray diffraction (XRD) analysis and Rietveld refinement show that the alloy consists of a single Pr5Co19-type phase. Electrochemical studies show that the alloy has a mediocre discharge capacity of 338mAhg−1 and good cycling stability. High rate dischargeability at 1500mAg−1(HRD 1500) reaches 51.5% and the corresponding discharge capacity remains 174mAhg−1. To improve overall electrochemical properties of the alloy, especially the discharge capacity, Ce2Ni7-type or LaNi5 secondary phase was introduced into the single-phase alloy by adjusting molar ratio of precursors. When the content of Ce2Ni7-type phase increases from 0 to 40.6wt.%, the maximum discharge capacity enhances from 338 to 388mAhg−1 and the discharge capacity retention at the 100th cycle is improved from 77.0% to 85.3%. With the presence of 20.7wt.% LaNi5 phase in the alloy, the HRD 1500 increases to 56% and the surface exchange current density (i 0) increases from 275.50mAg−1 to 354.16mAg−1.
The primary driver for development of organic photovoltaic (OPV) technologies is the prospect of very low cost module manufacture leading to affordable solar electricity. This paper presents an economic assessment of OPV based on an existing pre-industrial manufacturing process and the associated detailed material inventory. Using life cycle costing techniques, the life cycle investment cost for a 1kWp, grid-connected OPV system is calculated, taking into account the materials, direct process energy, labour, balance of system components, design and maintenance costs. Assuming values for the performance ratio of the PV system, insolation level, inflation and interest rates, the levelised electricity cost (LEC) is calculated. Under an average solar irradiance of 1700 kWh/m2/year, typical of southern Europe, a LEC of between 0.19 €/kWh and 0.50 €/kWh was calculated for a 1kWp system, based on modules containing 7% efficient cells and assuming a 5 year module lifetime. The OPV module is found to make up the majority of the system cost while the material costs constitute the largest contribution to the cost of the OPV module. The influence of OPV module lifetime is studied using sensitivity. This paper demonstrates that competitive solar electricity from OPV is within reach if efficiencies of ca. 7% already demonstrated in lab scale devices can be achieved in large area modules and if lifetimes of at least 5 years can be achieved.
Bioelectricity and triboelectrification are well-known and widely existing phenomena in nature, and the investigation of their mechanisms and utilizations has attracted much attention for a long time. As traditional investigations suggested, the mechanism of electric organs is that the electrocytes are lined up so a current of ions can flow through them, and thus they are stacked in a sequence so that each one adds up to form a potential difference. For varieties of triboelectric generators, most of them feature extremely high voltage but limited current, which is the major challenge to pracitcal utilization. Here, we present a structural bionic design based on the microstructure of electric organs to improve the output current of systematic triboelectric generators. This study correlating electric organs and triboelectric generators not only benefits the practical use of systematic triboelectric generators for energy harvesting, but also offers a new approach to imitate more compositive and tunable electronic devices from biological structures.
A small external magnetic field of 0.072T was reported to significantly influence the specific capacitances of the supercapacitor with magnetic carbon - metal (iron, cobalt or nickel) oxides microtubular nanocomposite fabrics as flexible electrodes. The decorated metal oxide species and annealing method (microwave-assisted vs. conventional tubular annealing) were discovered to play important roles in the increase or decrease of the capacitance. All the electrodes demonstrated excellent cycling retention performances, for example, upto ~350% for nickel oxide doped carbon nanocomposite electrodes. The corresponding mechanism for the magnetic field influence on the capacitance has been interpreted in term of a synergistic effect of three internal resistances, solution resistance in electrolyte solution, charge transfer resistance at electrode/electrolyte interface and leakage resistance in electric double layer region. The applied magnetic field is able to change the solution resistance due to the magnetohydrodynamic phenomena as well as the electrode resistance (directly corresponds to charge transfer resistance) by the magnetoresistance (MR) behavior.