batterydata/paper-abstracts huggingface dataset:
Transition metal fluorides (such as FeF3 and FeF2) based on conversion chemistry have been considered as a promising alternative to the intercalation cathode materials due to the high capacity and high energy density. However, the critical challenges for these materials come from the absence of Li source in them, and low power density and poor cycling stability. Herein, pre-lithiated FeF3 with extremely small size of Fe and LiF nanoparticles (both ∼6 nm) homogeneously embedded in the carbon matrix were synthesized using a facile and scalable in situ strategy. Benefited from the ultra-small Fe and LiF nanoparticles, uniform distribution, and intimate contact between the active species and the carbon matrix, the particle-to-particle interfacial resistance and diffusion length for Li and F are dramatically reduced. As a result, a high specific capacity of over 400 mA h g−1 with a discharge energy density of ∼700 W h kg−1 and favorable cycling performance are achieved, making such composite a promising high-capacity cathode for LIBs. Furthermore, the built-in Li source in this composite renders it a drop-in replacement for cathode materials used in the current LIB configurations, thus paving the way for the practical applications in the next generation of high energy density LIBs.
Peer-to-peer (P2P) energy sharing allows the surplus energy from distributed energy resources (DERs) to trade between prosumers in a community Microgrid. P2P energy sharing is being becoming more attractive than the conventional peer-to-grid (P2G) trading. However, intensive sensing and communication infrastructures are required either for information flows in a local market or for building a central control system. Moreover, the existing pricing mechanisms for P2P energy sharing could not ensure all the P2P participants gain economic benefits. This work proposed a two-stage aggregated control to realize P2P energy sharing in community Microgrids, where only the measurement at the point of common coupling (PCC) and one-way communication are required. This method allows individual prosumers to control their DERs via a third party entity, so called energy sharing coordinator (ESC). In the first stage, a constrained non-linear programming (CNLP) optimization with a rolling horizon was used to minimize the energy costs of the community. In the second stage, a rule based control was carried out updating the control set-points according to the real-time measurement. The benefits of P2P energy sharing were assessed from the community’s as well as individual customers’ perspective. The proposed method was applied to residential community Microgrids with photovoltaic (PV) battery systems. It was revealed that P2P energy sharing is able to reduce the energy cost of the community by 30% compared to the conventional P2G energy trading. The modified supply demand ratio based pricing mechanism ensures every individual customer be better off, and can be used as a benchmark for any P2P energy sharing model. For consumers, the electricity bill is reduced by ∼12.4%, and for prosumers, the annual income is increased by ∼£57 per premises.
The world is witnessing a change-over from its present centralized generation to a future with greater share of distributed generation. Hybrid energy systems are inter-connected with wind power, photovoltaic power, fuel cell and micro-turbine generator to generate power to local load and connecting to grid/micro-grids that decrease the dependence on fossil fuels. The hybrid system is a better option for construction of modern electrical grids that includes economic, environmental and social benefits. An overview of different distributed generation technologies has been presented. This paper puts forward a comprehensive review of optimal sizing, energy management, operating and control strategies and integration of different renewable energy sources to constitute a hybrid system. The feasibility of the different controllers such as microcontroller, proportional integral controller, hysteresis controller and fuzzy controller are presented. The controller is a closed loop feedback mechanism used for power regulation which achieves zero steady state error and the output signal generated from the controller produces desired output response.
The development of innovative automotive systems is determined by the demand for cut in fuel consumption and increase in fuel efficiency, reduction of environmental pollution and comfort improvement. A basic condition for such developments is the introduction of a 42V power supply in future vehicles. The characteristics of future power supplies and the resulting consequences for the system, the components and the whole vehicle power supply architecture need standardisation in different areas. The electrical stress for the vehicle components is addressed in the standard ISO 21848 and this paper gives details about the status of the standardisation work.
International Cancer Genome Consortium members review and recommend approaches to pathway and network analysis to uncover molecular processes that contribute to tumor biology.
The Co3O4 nanosheets electrode have been fabricated on Ni foam by a facile synthesis process including the electrodeposition of Co(OH)2 precursor followed by subsequent thermal transformation of precursor to Co3O4. The resulting Co3O4 nanosheets electrode exhibits an ultrahigh specific capacitance of 6469Fg−1 at a current density of 5mAcm−2, exceeding their theoretical value. Moreover, at density of 15mAcm−2, the specific capacitance maintains 4127Fg−1, with 81.6% retention after 2000 charge-discharge cycles. The work confirms the promising application of Co3O4 nanosheets as an efficient electrode for supercapacitors, and also offers a facile strategy to design and synthesis Co3O4 electrode with enhanced specific capacitance.
A smart city is a sustainable and efficient urban centre that provides a high quality of life to its inhabitants through optimal management of its resources. Energy management is one of the most demanding issues within such urban centres owing to the complexity of the energy systems and their vital role. Therefore, significant attention and effort need to be dedicated to this problem. Modelling and simulation are the major tools commonly used to assess the technological and policy impacts of smart solutions, as well as to plan the best ways of shifting from current cities to smarter ones. This paper reviews energy-related work on planning and operation models within the smart city by classifying their scope into five main intervention areas: generation, storage, infrastructure, facilities, and transport. More-complex urban energy models integrating more than one intervention area are also reviewed, outlining their advantages and limitations, existing trends and challenges, and some relevant applications. Lastly, a methodology for developing an improved energy model in the smart-city context is proposed, along with some additional final recommendations.
To mitigate mechanical and chemical degradation of active materials, hollow core–shell structures have been applied in lithium ion batteries. Without embedding of lithium ions, the rigid coating shell can constrain the inward volume deformation. In this paper, optimal conditions for the full use of inner hollow space are identified in terms of the critical ratio of shell thickness and inner size and the state of charge. It is shown that the critical ratios are 0.10 and 0.15 for Si particle and tube (0.12 and 0.18 for Sn particle and tube), and above which there is lack of space for further lithiation.
Polymer electrolytes were prepared by blending high molecular weight poly(ethylene oxide) (PEO) and a series of novel quaternary ammonium iodides, the polysiloxanes with oligo(oxyethylene) side chains and quaternary ammonium groups. X-ray diffraction (XRD) measurements ensured relatively low crystallinity when the quaternary ammonium iodides were incorporated into the PEO host. The ionic conductivity of these complexes was improved with the addition of plasticizers. The improvement in the ionic conductivity was determined by the polarity, viscosity and amounts of plasticizers. A plasticized electrolyte containing the novel quaternary ammonium iodide was successfully used in fabricating a quasi-solid-state dye-sensitized solar cell for the first time. The fill factor and energy conversion efficiency of the cell were calculated to be 0.68 and 1.39%, respectively.
This paper proposes a stochastic model for optimal energy management with the goal of cost and emission minimization. In this model, the uncertainties related to the forecasted values for load demand, available output power of wind and photovoltaic units and market price are modeled by a scenario-based stochastic programming. In the presented method, scenarios are generated by a roulette wheel mechanism based on probability distribution functions of the input random variables. Through this method, the inherent stochastic nature of the proposed problem is released and the problem is decomposed into a deterministic problem. An improved multi-objective teaching–learning-based optimization is implemented to yield the best expected Pareto optimal front. In the proposed stochastic optimization method, a novel self adaptive probabilistic modification strategy is offered to improve the performance of the presented algorithm. Also, a set of non-dominated solutions are stored in a repository during the simulation process. Meanwhile, the size of the repository is controlled by usage of a fuzzy-based clustering technique. The best expected compromise solution stored in the repository is selected via the niching mechanism in a way that solutions are encouraged to seek the lesser explored regions. The proposed framework is applied in a typical grid-connected micro grid in order to verify its efficiency and feasibility.
Electron emission can be utilised to measure the work function of the surface. However, the number of significant digits in the values obtained through thermionic-, field- and photo-emission techniques is typically just two or three. Here, we show that the number can go up to five when angle-resolved photoemission spectroscopy (ARPES) is applied. This owes to the capability of ARPES to detect the slowest photoelectrons that are directed only along the surface normal. By using a laser-based source, we optimised our setup for the slow photoelectrons and resolved the slowest-end cutoff of Au(111) with the sharpness not deteriorated by the bandwidth of light nor by Fermi-Dirac distribution. The work function was leveled within  ±0.4 meV at least from 30 to 90 K and the surface aging was discerned as a meV shift of the work function. Our study opens the investigations into the fifth significant digit of the work function.
With the rapid development of battery-powered electric vehicles, the lithium-ion battery plays a critical role in the reliability of vehicle system. In order to provide timely management and protection for battery systems, it is necessary to develop a reliable battery model and accurate battery parameters estimation to describe battery dynamic behaviors. Therefore, this paper focuses on an on-board adaptive model for state-of-charge (SOC) estimation of lithium-ion batteries. Firstly, a first-order equivalent circuit battery model is employed to describe battery dynamic characteristics. Then, the recursive least square algorithm and the off-line identification method are used to provide good initial values of model parameters to ensure filter stability and reduce the convergence time. Thirdly, an extended-Kalman-filter (EKF) is applied to on-line estimate battery SOC and model parameters. Considering that the EKF is essentially a first-order Taylor approximation of battery model, which contains inevitable model errors, thus, a proportional integral-based error adjustment technique is employed to improve the performance of EKF method and correct model parameters. Finally, the experimental results on lithium-ion batteries indicate that the proposed EKF with proportional integral-based error adjustment method can provide robust and accurate battery model and on-line parameter estimation.
Thermal management is one of the key factors to keep lithium-ion cells in optimum electrical performance, under safe working conditions and into a reasonably low ageing process. This issue is becoming particularly relevant due to the heterogeneous heat generation along the cell. Cell working temperature is determined by ambient temperature, heat generation and evacuation capacity. Therefore, thermal management is established by: i) the intrinsic thermal properties (heat capacity & thermal conductivity) and ii) the heat generation electro-thermal parameters (internal resistance, open circuit voltage & entropic factor). In this research, different methods - calculated and experimental - are used to characterize the main heat properties of a 14Ah -LiFePO4/graphite-commercial large sizes pouch cell. In order to evaluate the accuracy of methods, two comparisons were performed. First, Newman heat generation estimations were compared with experimental heat measurements. Secondly, empirical thermal cell behaviour was match with 1D electro-thermal model response. Finally, considering the results, the most adequate methodology to evaluate the key thermal parameters of a large size Lithium-ion pouch cell are proposed to be: i) pulse method for internal resistance, ii)heat loss method for entropic factor; and iii)experimental measurement (ARC calorimeter and C-177-97 standard method) for heat capacity and thermal conductivity.
The LiNi1/3Co1/3Mn1/3O2/Ag composite used for cathode material of lithium ion battery was prepared by thermal decomposition of AgNO3 added to commercial LiNi1/3Co1/3Mn1/3O2 powders to improve the electrochemical performance of LiNi1/3Mn1/3Co1/3O2. Structure and morphology analysis showed that Ag particles were dispersed on the surface of LiNi1/3Co1/3Mn1/3O2 instead of entering the crystal structure. The results of charge–discharge tests showed that Ag additive could improve the cycle performance and high-rate discharge capability of LiNi1/3Mn1/3Co1/3O2. Extended analysis indicated that Ag was unstable in the commercial electrolyte at high potential. The improved electrochemical performance caused by Ag additive was associated not only with the enhancement of electrical conductivity of the material and the lower polarization of the cell, but also with the increased “c” parameter of LiNi1/3Mn1/3Co1/3O2 after repeated charge/discharge cycles and the compact and protective SEI layer formed on the surface of LiNi1/3Mn1/3Co1/3O2.
Direct electrostatic interactions between a charged Pt surface and oppositely charged spectator ions are utilized for the enhancement of oxygen reduction reaction (ORR) activity in both KOH and H3PO4 solutions. Zwitterionic L-cysteine molecules functionalized on a Pt surface are turned outwards to afford differing surface charges in either alkaline (−) or acid solutions (+). In KOH solution, this leads to the selective impediment of interactions between OH− and K+ with the Pt surface through repulsive and attractive interactions of the negatively charged –COO− group of L-cysteine, respectively. In H3PO4 solution, the phosphoric acid molecule and its anion are effectively captured by the positively charged –NH3+ moieties of L-cysteine. Behaviors of the spectator species hindering the ORR are systematically controlled through direct electrostatic interactions with the functional groups of L-cysteine in each electrolyte, resulting in a Janus Pt catalyst for superior ORR in both alkaline and acid electrolytes.
Li3V2(PO4)3/C (LVP/C) cathode materials for lithium ion batteries have been successfully synthesized via carbon thermal reduction method using pitch as both a new carbon source and a reduction agent. The influences of different carbon sources (pitch, Super P, KS15 and Vulcan-XC72) and heat treatments between 650 and 950°C on the LVP/C materials have also been investigated. The structural and electrochemical properties of the samples are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM) and high resolution transmission electron microscopy (HRTEM) as well as charge-discharge experiments. The LVP/C synthesized with pitch have smooth surface with uniform residue carbon distribution and presents the best electrochemical performance. In addition, the oxidation of carbon has been discussed. The results indicate that carbons obtained from four carbon sources are tended to be oxidized to CO2 than CO. Electrochemical tests show the LVP/C-750°C exhibits the highest discharge capacity and the most excellent capacity retention. Spherical LVP/C particles are obtained using the spray drying method. The spray drying-LVP/C composite deliver higher discharge capacity than those of LVP/C composites obtained by carbon thermal reduction method or by drying with oven.
A semimicro-size agglomerate structured silicon-carbon (mSi-C) composite is constructed by an aggregation of silicon nanoparticles (∼100 nm) coated with conductive carbon layer through a facile and scalable aerosol-assisted process to be employed as an anode material for lithium-ion batteries (LIBs). As-formed mSi-C composite delivers good electrochemical performances of high reversible capacity (2084 mAh/g) between 0.01 and 1.50 V (vs. Li/Li+) at 0.4 A/g, 96% capacity retention (1999 mAh/g) after 50 cycles and good rate capability (906 mAh/g) at 12 A/g. Such good performances can be attributed to 1) unique composite structure which accommodates the stress induced by volume change of silicon during lithiation/delithiation and facilitates ion transport, and 2) conformally formed carbon layer which enhances conductivity of the composite and helps to form a stable SEI layer. In addition, a high tap density (0.448 g/cm3) of mSi-C composite leads to high volumetric capacity (933 mAh/cm3), allowing its practical applications as an anode material towards high performance LIBs.
The clean energy transition requires a co-evolution of innovation, investment, and deployment strategies for emerging energy storage technologies. A deeply decarbonized energy system research platform needs materials science advances in battery technology to overcome the intermittency challenges of wind and solar electricity. Simultaneously, policies designed to build market growth and innovation in battery storage may complement cost reductions across a suite of clean energy technologies. Further integration of R&D and deployment of new storage technologies paves a clear route toward cost-effective low-carbon electricity. Here we analyse deployment and innovation using a two-factor model that integrates the value of investment in materials innovation and technology deployment over time from an empirical dataset covering battery storage technology. Complementary advances in battery storage are of utmost importance to decarbonization alongside improvements in renewable electricity sources. We find and chart a viable path to dispatchable US$1 W−1 solar with US$100 kWh−1 battery storage that enables combinations of solar, wind, and storage to compete directly with fossil-based electricity options.
In this work, Na2Ti3O7 is fabricated as lithium storage material via one-step solid state reaction. Worked as anode material, Na2Ti3O7 delivers a stable electrochemical performance with good lithium storage capability. Structural analyses show that Na2Ti3O7 anode experiences slight volume change during electrochemical lithiation/delithiation process. Moreover, the reversibility of structural evolution is further demonstrated by in-situ X-ray diffraction technique. All these evidences prove the cycling stability of Na2Ti3O7 as lithium storage material. Besides, the kinetic properties of the Li+ ion storage in Na2Ti3O7 are systematically investigated. The observed results reveal that Na2Ti3O7 delivers the lithium ions diffusion coefficient in the range of 10−14–10−12 cm2 s−1 during the discharge process and 10−15–10−12 cm2 s−1 during the recharge process. It suggests that Na2Ti3O7 has good lithiation/delithiation kinetics in rechargeable batteries.
Despite the intensive studies of combining silicon (Si) and reduced graphene oxide (rGO), the architecture of Si–rGO composites still needs to be improved to maintain better electrode structure integrity and stable solid electrolyte interphase (SEI) upon extensive cycling. Herein, a conductive and protective network with rGO and CVD-implemented carbon is constructed with silicon nanoparticles (Si NPs) embedded inside for the first time. Compared with the regular Si–rGO composite with only Si NPs wrapped by rGO, Si–rGO–C composite successfully improves the electrical conductivity and structure stability. In addition to the wrapping of rGO on Si NPs, the additional carbon layer on the partially exposed Si NPs provides extra protection from fracture during volume change and helps form a stable SEI layer. Carbon rods between rGO flakes function as conductive bridges, creating an effective conductive network on a macroscopic scale. The initial capacity of Si–rGO–C composite reaches 1139mAhg−1 and 894mAhg−1 at 0.1Ag−1 and 1C respectively, and retains 94% of its initial capacity after 300 cycles at 1C. The electrode is stabilized at 770mAhg−1 at 2C during rate performance testing.
In this work, we present an ensemble for automated audio classification that fuses different types of features extracted from audio files. These features are evaluated, compared, and fused with the goal of producing better classification accuracy than other state-of-the-art approaches without ad hoc parameter optimization. We present an ensemble of classifiers that performs competitively on different types of animal audio datasets using the same set of classifiers and parameter settings. To produce this general-purpose ensemble, we ran a large number of experiments that fine-tuned pretrained convolutional neural networks (CNNs) for different audio classification tasks (bird, bat, and whale audio datasets). Six different CNNs were tested, compared, and combined. Moreover, a further CNN, trained from scratch, was tested and combined with the fine-tuned CNNs. To the best of our knowledge, this is the largest study on CNNs in animal audio classification. Our results show that several CNNs can be fine-tuned and fused for robust and generalizable audio classification. Finally, the ensemble of CNNs is combined with handcrafted texture descriptors obtained from spectrograms for further improvement of performance. The MATLAB code used in our experiments will be provided to other researchers for future comparisons at https://github.com/LorisNanni.
Α new type of a high temperature liquid metal-air energy storage cell based on solid oxide electrolyte has been successfully demonstrated at 750 °C by feeding metal Sn. In order to understanding the initial size effect of metal as a liquid fuel, we report here the impact of the thermal and electrochemical oxidation behavior of nano Sn (∼100 nm), comparing with micro-sized (∼5 µm) and macro-sized (∼350 µm) Sn. The thermogravimetric analysis and the monitoring OCV test indicate that the distinct property of nano-sized Sn results in a favorable thermal oxidation behavior near the melting point and a promising power performance due to enhanced fuel transport to the anode. However, the accumulated Sn oxide at the reaction interface during a discharge test towards the limitation of further electrochemical oxidation.
Lead phosphate was used as an intrinsic phosphorous-doped lead composite oxide in rechargeable lithium test batteries. For comparison the amorphous polymorph was prepared from the crystalline form by melt-quenching. The experimental results are analogous to tin composite oxide (TCO) anodes, with the amorphous form showing a higher capacity and better cyclability. The mechanism for rechargeability and the cause for capacity loss in the first cycle are also proposed.