batterydata/paper-abstracts huggingface dataset:
In order to address the trade-off between the safety lithium ion battery (LIB) electrolytes and their electrochemical performance, synergetic effects of flame retardant additives (FRs) in combination with film forming additives (FFAs) are investigated. Triphenyl phosphate (TPP) and a silicon-containing additive (WA) are applied as FRs to improve the onset temperature of the thermal runaway of a LIB standard electrolyte (LP57: 1 M LiPF6 in EC:EMC 3:7) about 15 K and 28 K, respectively. The application of the FRs in MCMB graphite/lithium metal and NMC111/lithium metal three-electrode cells induces insufficiencies in terms of charge/discharge cycling stability and rate capability. It is investigated if the addition of FFAs can degrade the insufficiencies that are induced by the FRs. Vinylene carbonate, vinyl ethylene carbonate and fluoroethylene carbonate are added to a mixture of LP57 with 10% FR to enhance the cycling performance via improved interphase formation. Results reveal, that the rate capability of cells containing TPP or WA is especially improved by addition of 2% or 5% FEC, respectively. Postmortem analyses of the electrodes by SEM and of the electrolyte by GC-MS are performed. Direct correlations between the cycling behavior during the C-rate study and the electrolyte decomposition products are drawn.
In this paper, we describe a novel red-to-gray poly(3-methylthiophene) (PMeT) electrochromic device (ECD) with the aid of a zinc hexacyanoferrate (ZnHCF)/PEDOT:PSS counter electrode. The application of ZnHCF to an ECD is first reported. ZnHCF has long suffered from poor deposition yield problem, but we demonstrate that a robust ZnHCF film can be prepared by spin coating of a liquid suspension composed of ZnHCF nanoparticles and PEDOT:PSS ink on ITO. It was found that the ZnHCF/PEDOT:PSS composite worked much better with PMeT than pure ZnHCF or pure PEDOT:PSS from both electrochemical and optical aspects. With a LiClO4/PC electrolyte, the PMeT ECD having ZnHCF/PEDOT:PSS as its counter electrode could be reversibly switched between its red state (>0.8V) and its gray state (<0V). For a 2cm×2cm prototype device, the response time for coloration was less than 1s. The maximum transmittance modulation of the device could attain 45.3% at 750nm, which resulted in a corresponding coloration efficiency of 336.8cm2/C. The maximum contrast ratio was 5.45 at 720nm. In addition, the charge capacity of the ECD could retain 95% of its original value after 10,000 cycles of cyclic voltammetry aging test, although an electrodeposited PMeT film alone could be cycled several hundred times only. To sum up, this work proposes a new, cost-effective transparent counter electrode and brings a stable, high visual-contrast PMeT ECD prototype for further development of a red-color bistable display.
Currently, the grid-connected large PV farms are extensively installed in power systems. Nevertheless, in addition to the load change, the intermittent power output of PV farms may lead to the serious problem of the system frequency fluctuation. To handle this problem, this paper proposes a new design of Sugeno fuzzy logic controller based on particle swarm optimization (PSO-SFLC) of intelligent PV farms for the frequency stabilization in a multi-area interconnected power system. To handle various scenarios, the frequency deviations and solar insolations are used as input signals of the PSO-SFLC. The output signal of the PSO-SFLC is a command signal for adjusting PV output power. The output power of PV is controlled by the PSO-SFLC to meet the load demand so that the system frequency fluctuation can be suppressed. Without the difficulty of trial and error, the optimal input and output membership functions, and control rules of PSO-SFLC are automatically achieved by PSO. Simulation study in a three-area loop interconnected power system with large PV farms elucidates that the frequency stabilizing performance and robustness of the PV equipped with the PSO-SFLC is much superior to that of the PV with the SFLC and the PV with the maximum power point tracking control in scenarios with various solar insolations and loading conditions.
Vanadium dioxide (VO2) is one of the most widely studied inorganic phase change material for energy storage and energy conservation applications. Monoclinic VO2 [VO2(M)] changes from semiconducting phase to metallic rutile phase at near room temperature and the resultant abrupt suppressed infrared transmittance at high temperature makes it a potential candidate for thermochromic smart window application to cut the air-condition usage. Meanwhile proper electrical potential, stable structure and good interaction with lithium ions make metastable VO2 [VO2(B)] an attractive material for fabrication of electrodes for batteries and supercapacitors. However, some long-standing issues have plagued its usage. In thermochromic application, high transition temperature (τ c), low luminous transmittance (T lum) and undesirable solar modulation ability (△T sol) are the key problems, while in energy storage applications, short cycling lifetime and complex three-dimension microstructure are the major challenges. The common methods to produce VO2 polymorph are physical vapour deposition (PVD), chemical vapour deposition (CVD), sol-gel synthesis, and hydrothermal method. CVD is an intensively studied method due to its ability to produce uniform films with precise stoichiometry, phase and morphology control. This paper reviews the various CVD techniques to produce VO2 with controlled phases and the ternary diagram shows the relationship between film stoichiometry and various process conditions. The difference between the various CVD systems are commented and the process window to produce VO2 are tabulated. Some strategies to improve VO2′s performance in both energy conservation and energy storage applications are discussed.
Battery electric vehicles (BEVs) offer the potential to reduce both oil imports and greenhouse gas emissions, but have a limited utility that is affected by driver aggression and effects of climate—both directly on battery temperature and indirectly through the loads of cabin and battery thermal management systems. Utility is further affected as the battery wears through life in response to travel patterns, climate, and other factors. In this paper we apply the National Renewable Energy Laboratory's Battery Lifetime Analysis and Simulation Tool for Vehicles (BLAST-V) to examine the sensitivity of BEV utility to driver aggression and climate effects over the life of the vehicle. We find the primary challenge to cold-climate BEV operation to be inefficient cabin heating systems, and to hot-climate BEV operation to be high peak on-road battery temperatures and excessive battery degradation. Active cooling systems appear necessary to manage peak battery temperatures of aggressive, hot-climate drivers, which can then be employed to maximize thru-life vehicle utility.
Three types of carbon nano-onions (CNOs) including Ni@CNOs, Fe3C@CNOs and Fe0.64Ni0.36@CNOs nanoparticles have been synthesized by catalytic decomposition of methane at 850 °C using nickel, iron and iron-nickel alloy catalysts. Comparative and systematic studies have been carried out on the morphology, structural characteristics and graphitic crystallinity of these CNOs products. Furthermore, the electrochemical hydrogen storage properties of three types of CNOs have been investigated. Measurements show that the Ni@CNOs have the highest discharge capacity of 387.2 mAh/g, corresponding to a hydrogen storage of 1.42%. This comparison study shows the advantages of each catalyst in the growth of CNOs, enabling the controllable synthesis and tuning the properties of CNOs by mediating different metals and their alloy for using in the fuel cell system.
An important outcome of any clinical intervention is the change in the subject's own perceived state of health. This can be categorized as health-related quality of life (HRQL), utility (preference-based health state), and daily life performance. 174 Swedish subjects with chronic obstructive pulmonary disease (COPD) (mean age 64.3 ± 12 years) completed five self-administered questionnaires: Short Form 36 (SF-36), St George's Respiratory Questionnaire (SGRQ), EuroQol-5D (EQ-5D), Health States-COPD (HS-COPD), and Work Productivity and Activity Impairment Questionnaire for COPD (WPAI-COPD). The subjects scored these outcomes instruments for ease of completion using a 5-point scale. The time taken to complete them was noted and the administrators' opinion of the subjects' comprehension of the questionnaires recorded using a 4-point scale.
For the issue of users’ sensibility to the QoS (Quality of Service) of multimedia applications, cloudlet has emerged as a novel paradigm which provides closer computing resources to users to improve the performance of multimedia applications and meet the QoS demands of users. However, the increasing users’ requirements of migrating tasks pose a challenge to preserve the security and integrity of offloaded data which are processed by cloudlets. In view of this challenge, a blockchain-based cloudlet management method for multimedia workflow, named MWSM, is proposed in this paper. Technically, we first model each multimedia application as a multimedia workflow and formulate the multimedia workflow scheduling problem. Then, blockchain is adopted to secure the data integrity during the offloading procedure. Besides, NSGA-III (Non-dominated Sorting Genetic Algorithm III) is employed to realize the QoS enhancement and ELECTRE (Elimination Et Choix Tradulsant la REaltite) is utilized to solve the decision-making problems of the most optimal scheduling strategies. Finally, experimental evaluations are conducted to demonstrate the efficiency and potential of our proposed scheduling method.
Integrating renewable energy sources into conventional power system is a solution to the horrendous problems of environmental pollution and global energy crisis. But the uncertain nature of renewable sources inspires the researchers to combine different energy sources as well as energy storage devices to ensure power supply reliability. In this paper, an intelligent energy management system (EMS) algorithm is proposed which dictates the power flow among the hybrid renewable system, energy storage and the grid for two cases. Different energy storage systems are considered. Their suitability for use in the proposed system is evaluated. With the appropriate storage system two different cases are considered for fixed and variable load. Each case is studied for three hypotheses i.e. grid, energy storage and optimal grid and energy storage participation. Optimal participation of both the grid and energy storage systems poses maximum financial benefit of 3190.50 INR and 2513.70 INR for both types of loads. This paper also compares the economic impacts of using solar PV panels and ESSs both in standalone and grid connected modes.
Radio Frequency Identification (RFID) systems are widely used in access control, transportation, real-time inventory and asset management, automated payment systems, etc. Nevertheless, the use of this technology is almost unexplored in healthcare environments, where potential applications include patient monitoring, asset traceability and drug administration systems, to mention just a few. RFID technology can offer more intelligent systems and applications, but privacy and security issues have to be addressed before its adoption. This is even more dramatical in healthcare applications where very sensitive information is at stake and patient safety is paramount. In Wu et al. (J. Med. Syst. 37:19, 43) recently proposed a new RFID authentication protocol for healthcare environments. In this paper we show that this protocol puts location privacy of tag holders at risk, which is a matter of gravest concern and ruins the security of this proposal. To facilitate theimplementation of secure RFID-based solutions in the medical sector, we suggest two new applications (authentication and secure messaging) and propose solutions that, in contrast to previous proposals in this field, are fully based on ISO Standards and NIST Security Recommendations.
The sodium–oxygen (Na–O2) battery is proposed as one of the most promising energy storage technologies due to its high energy density and the abundance of sodium resources; however, its applications still suffer from low energy efficiency and poor cycle stability and rate performance due to the absence of highly efficient electrocatalysts. Herein, as a proof-of-concept experiment, we, for the first time, develop a facile and solid-state reaction strategy for controllable synthesis of porous cobalt boride (CoB) nanosheets with the help of inorganic molten salts. Surprisingly, when CoB nanosheets are employed as cathode catalysts for Na–O2 batteries for the first time, significantly improved electrochemical performances are obtained, such as a low charge overpotential, good rate capability, and a high specific capacity (11482 mA h g−1) and cycle life (74 cycles), which, in combination with density functional theory, could be attributed to the synergy of high catalytic activity and electronic conductivity and the porous sheet structure of CoB. This experimentally and theoretically established metallic transition metal borides as intriguing electrocatalysts could trigger more studies on other energy storage and conversion systems.
In this study, the deterioration of lithium iron phosphate (LiFePO4) /graphite batteries during cycling at different discharge rates and temperatures is examined, and the degradation under high-rate discharge (10C) cycling is extensively investigated using full batteries combining with post-mortem analysis. The results show that high discharge current results in an instability of electrode/electrolyte interface and unstable solid electrolyte interphase (SEI) layers are expected to form on the newly exposed graphite anode surface, which cause sustainable consumption of active lithium and further lead to the performance degradation of active materials. For LiFePO4 cathode, the initial capacity is largely recovered under low rate (0.1-0.2C), whereas a decline in the capability is observed at higher rates (0.5-3.0C). For graphite anode, half-cell study shows that considerable capacity loss occurs even at low rates. A small amount of Fe deposition is observed on graphite anode after cycling under 10C discharge at 55°C. X-ray photoelectron spectroscopy (XPS) analysis confirms that a layer composed of lithium compounds is formed on the surface of anode, which can not participate in the reversible electrochemical reaction again. In addition, electrochemical impedance spectrum (EIS) measurements of half-cell indicate that the increased resistance of the positive electrode is suggested to be the root cause of power fading under high-rate discharge cycling, especially at high temperature.
This paper deals with the real-time implementation of a robust control for electric vehicles, supplied by a battery/capacitor super capacitor hybrid energy storage system (HESS) and piloted via a permanent magnet synchronous motor (PMSM). The main goals are to monitor the motor using the back-stepping control and to provide an efficient power management. This has been implemented by means of the DC bus regulation using an H ∞ regulator, while a classical regulator is used to ensure a super capacitor (SC) voltage allowing a maximal availability during repetitive peak power, in order to ensure an optimal power flow to the load as well as to keep the SC operation in a safe voltage range. This original algorithm has been validated through experimental results provided by a tailor made test bench including both the HESS and the vehicle emulation controlled via two dSPACE 1104 cards. Furthermore, the back-stepping controller shows good dynamic performances, where the system reaches to track perfectly the speed profile, under tolerable torque and flux ripples.
A novel class of electrochemical supercapacitor electrode material has been electrochemically synthesized from a manganese halide complex in water-containing acetonitrile electrolyte at room temperature. This material has been physically and chemically characterized by scanning electron microscopy, X-ray photoelectron microscopy (XPS), FT-Raman microscopy and cyclic voltammetry. XPS and FT-Raman characterization suggest that this material is composed of manganese oxide with a chemical composition of Mn3O4 and containing a moderate amount of carbon. Cyclic voltammetric characterization indicates that this material has higher electronic conductivity than usually seen for manganese oxide and that it shows fast kinetics for the charge–discharge process in both aqueous and acetonitrile electrolytes. The material provides a large pseudocapacitance over a potential window of about 1 V in aqueous electrolyte and about 2 V in acetonitrile electrolyte. It is therefore a good candidate as a material for an electrochemical supercapacitor electrode.
Thanks to low cost and high safety, aqueous zinc-ion batteries (AZIBs) are attractive candidates for large-scale energy storage applications, while suitable cathode materials are needed urgently. In this work, δ-NaxV2O5·nH2O with a large interlayer spacing of 10.6 Å is reported as the cathode material for aqueous zinc-ion batteries for the first time. It is found that δ-NaxV2O5·nH2O performs better than Na2V6O16·nH2O under the same condition, and its electrochemical performances can be significantly improved after hybridizing it with reduced graphene oxide. The obtained nanocomposite can deliver high reversible capacity of 433.5 mAh g−1 at 0.1 A g−1, superior rate capability of 244.1 mAh g−1 at 5 A g−1, and good cyclability of 70.5% over 1000 cycles. Such great performances origin from the synergetic effect of δ-NaxV2O5·nH2O and graphene, which enables rapid Zn2+ diffusion and large capacitive contribution. Besides, the ex-situ measurement results demonstrate good structural stability and reversible Zn2+ ion storage behavior of reduced graphene oxide/δ-NaxV2O5·nH2O nanocomposite. This work extends the knowledge into the material technology of AZIBs.
Mg rechargeable batteries are a highly perspective battery system for the future post Li-ion batteries. However, their practical application seems quite distant due to poor Mg2+ insertion into inorganic cathode materials. Organic cathodes offer an opportunity for realization of practical Mg rechargeable batteries due to circumvention of insertion limitations encountered in inorganic hosts. Herein, we investigate the electrochemical performance of polyanthraquinone (PAQ) organic cathode in two Mg electrolytes based on different combinations of the salts, Mg(TFSI)2-2MgCl2 and MgCl2-AlCl3. PAQ in electrolyte containing Mg(TFSI)2-2MgCl2 exhibits good capacity retention and utilization. MgCl2-AlCl3 based electrolyte shows poorer electrochemical performance and a peculiar upshift of the voltage plateau for 300 mV, which is caused by the presence of AlCl3 in the electrolyte. Mg anode morphology after cycling reveals the formation of pits and cracks on the Mg foil anode as well as uneven Mg deposits several μm in size in both electrolytes. The maximum capacity and capacity retention are referenced with polyanthraquinone performance in Li battery and show that at 1C cycling rate 75% of the maximum capacity in Li battery can be obtained in Mg battery. Long-term capacity fade is comparable, demonstrating the potential for practical realization of Mg‒organic battery.
We report on the Li electrochemical reactivity of amorphous and crystalline VP2, synthesized by ball-milling and by 600°C heat treatment of a ball-milled sample, respectively. The amorphous sample can reversibly react with 3.5 Li per formula unit as compared to solely 2.5 for the crystalline one. However in both cases there is a rapid capacity decay upon cycling that is more pronounced in the case of the crystalline sample. Complementary X-rays, HTREM and NMR tend to show that the Li reactivity mechanism differs from the classical conversion reactions since neither V nanoparticles nor the formation of Li3P were detected, as opposed to some of the other MP2 compounds (M=Ni or Cu). Besides structural phase variations within the 3d metal-based binary phosphide series, the possibility of a change in the nature of the redox centre upon lithiation from cation (M) to anion (P) is evoked.
Many people throughout the world are remote from electricity networks and do not have access to reliable power. Remote-area power-supply (RAPS) systems offer a reliable and cost-effective alternative to grid connection. Achieving adequate performance from such systems requires appropriate componentry and well-designed control systems/strategies. A relatively new operating methodology—known as partial-state-of-charge (PSoC) operation—is now finding application in the field. The strategy, which can give a three-fold increase in the lifetime energy-delivery of gelled-electrolyte batteries compared with that obtained using traditional charging procedures, is to be employed in RAPS systems in Peru. The PSoC algorithms will be formulated and trailed in the laboratory, and then installed in the Peru facilities where they will be monitored and controlled remotely via a satellite link-up. This approach allows the algorithms to be fine-tuned in situ, and will ensure that system efficiency and battery lifetime are maximised. Use of the PSoC concept is expected to provide a battery lifetime of 8 years.
The hybrids of metal-based materials supported by carbon nanofibers (CNFs) have potential application in reversible energy storage devices. In this work, four kinds of CoCO3 micrometer particles stabilized in the network of CNFs are designed and synthesized by using solvothermal method. The composite electrodes of cubic-CoCO3/CNF, spherical-CoCO3/CNF, spindle-CoCO3/CNF and dumbbell-CoCO3/CNF deliver the initial specific capacities of 1190, 987, 1193 and 1108 mAh g−1, respectively, and remain 503, 584, 666, 551 mAh g−1 at the 100th cycle. Bare spindle CoCO3 delivers the highest capacity of 1588 mAh g−1, but CoCO3 without the support of CNFs only remains 140 mAh g−1 at the 100th cycle. Spindle-CoCO3/CNF composite electrode exhibits the best rate performance, delivering 507 mAh g−1 at the current density of 1.0 A g−1. The ex-situ field emission scanning electron microscope (FESEM) images show that CNFs elastically buffer the volume change of CoCO3 during lithiation/delithiation cycles. CNFs as substrate play the important roles in providing excellent conductive channel to improve the rate capability and effective matrix buffering the volume change to promote the cyclic performance. This work presents a scalable approach to synthesize and optimize the hybrid structure of CoCO3/CNF for potential application in highly reversible lithium storage devices.
Used batteries contain numerous metals in high concentrations and if not disposed of with proper care, they can negatively affect our environment. These metals represent 83% of all spent batteries and therefore it is important to recover metals such as Zn and Mn, and reuse them for the production of new batteries. The recovery of Zn and Mn from used batteries, in particular from Zn–C and alkaline ones has been researched using hydrometallurgical methods. After comminution and classification of elemental components, the electrode paste resulting from these processes was treated by chemical leaching. Prior to the leaching process the electrode paste has been subjected to two washing steps, in order to remove the potassium, which is an inconvenient element in this type of processes. To simultaneously extract Zn and Mn from this paste, the leaching method in alkaline medium (NaOH solution) and acid medium (sulphuric acid solution) was used. Also, to determine the efficiency of extraction of Zn and Mn from used batteries, the following variables were studied: reagents concentration, S/L ratio, temperature, time. The best results for extraction yield of Zn and Mn were obtained under acid leaching conditions (2M H2SO4, 1h, 80°C).