batterydata/paper-abstracts huggingface dataset:
Single-ion conducting polymer electrolytes represent the ideal solution to reduce concentration polarization in lithium metal batteries (LMBs). This paper reports on the synthesis and characterization of single-ion ABA triblock copolymer electrolytes comprising PEO and poly(lithium 1-[3-(methacryloyloxy)propylsulfonyl]-1-(trifluoromethylsulfonyl)imide) blocks, poly(LiMTFSI). Block copolymers are prepared by reversible addition-fragmentation chain transfer polymerization, showing low glass transition temperature (−55 to 7 °C) and degree of crystallinity (51–0%). Comparatively high values of ionic conductivity are obtained (up to ≈ 10−4 S cm−1 at 70 °C), combined with a lithium-ion transference number close to unity ( t L i + ≈ 0.91) and a 4 V electrochemical stability window. In addition to these promising features, solid polymer electrolytes are successfully tested in lithium metal cells at 70 °C providing long lifetime up to 300 cycles, and stable charge/discharge cycling at C/2 (≈100 mAh g−1).
Understanding the sodium (Na) chemistry is crucial for development of high-performance sodium ion batteries (SIBs). Nanostructured bismuth (Bi) has shown great potentials as an anode in SIBs, however, the Na storage mechanisms of Bi are still unclear. Herein, the operando X-ray diffraction (XRD) technique was utilized to probe the Na storage mechanisms of three Bi anodes (sputtered Bi film, nanoporous Bi and commercial Bi). Despite different morphologies and sizes, all the Bi anodes follow the same two-step reversible alloying/dealloying mechanisms (Bi ↔ NaBi ↔ Na3Bi) during the discharge/charge processes, associated with two voltage plateaus. As for the intercalation/deintercalation mechanism proposed for nanostructured Bi anodes in SIBs, we rationalize the reason why only the Bi phase is detected in the discharged/charged samples under ex-situ XRD conditions through addressing the stability issue of the Na-Bi system (NaBi and Na3Bi).
Graphene nanosheets (GNs) dispersed with SnO2 nanoparticles loaded multiwalled carbon nanotubes (SnO2–MWCNTs) were investigated as electrode materials for supercapacitors. SnO2–MWCNTs were obtained by a chemical method followed by calcination. GNs/SnO2–MWCNTs nanocomposites were prepared by ultrasonication of the GNs and SnO2–MWCNTs. Electrochemical double layer capacitors were fabricated using the composite as the electrode material and aqueous KOH as the electrolyte. Electrochemical performance of the composite electrodes were compared to that of pure GNs electrodes and the results are discussed. Electrochemical measurements show that the maximum specific capacitance, power density and energy density obtained for supercapacitor using GNs/SnO2–MWCNTs nanocomposite electrodes were respectively 224Fg−1, 17.6kWkg−1 and 31Whkg−1. The fabricated supercapacitor device exhibited excellent cycle life with ∼81% of the initial specific capacitance retained after 6000 cycles. The results suggest that the hybrid composite is a promising supercapacitor electrode material.
Polymer electrolytes containing solvate ionic liquids (SILs) with increased toughness for use in lithium secondary batteries were designed by utilizing the self-assembly of ABA-type ionomer triblock copolymer, where the A-blocks are ionomers having strong intermolecular coulombic interactions. The ABA-type triblock copolymer, poly(lithium acrylate-r-acrylic acid)-b-poly(methyl methacrylate)-b-poly(lithium acrylate-r-acrylic acid) (P(LiA-r-AA)-b-PMMA-b-P(LiA-r-AA), denoted LML), was synthesized and used as the polymer electrolytes host matrix. The fundamental properties, such as rheological, mechanical, and electrochemical properties, were explored for a binary system (ion gel) comprising LML and a hydrophobic ionic liquid. Due to the strong Li+-carboxylate interactions, the tensile fracture energy of the ion gel was greatly enhanced compared to those of conventional block copolymer electrolytes using nonionic polymers, indicating that the use of the ionomer in the A-block contributed to an enhancement in the tensile strength. Furthermore, the polymer electrolytes prepared with SILs showed good Li+-conductivity and thermal stability. Electrochemical potential window of the polymer electrolytes, revealed by voltammetry, demonstrated their oxidation stability up to 4.5V vs. Li/Li+ and reversible lithium deposition and dissolution.
In order to attain emissions reduction targets to improve air quality and reduce global warming, electric vehicles (EVs) arise as alternatives to conventional vehicles fueled by fossil fuels. In this context, this work presents a comparative study between an EV and its conventional version, a medium-duty, diesel engine powered vehicle, from road tests following a standard cycle in urban driving conditions. The performance parameters evaluated are EV electric energy consumption and carbon dioxide (CO2) emissions from electricity generation and, for the conventional vehicle, exhaust CO2 emissions and energy consumption calculated from fuel consumption and heating value. Five scenarios were built to conduct an economic viability study in terms of payback and net present value (NPV). Considering the conditions applied, the results from the environmental analysis showed that CO2 emissions from the EV was 4.6 times lower in comparison with the diesel vehicle. On the other hand, the economic analysis revealed that the viability of the EV is compromised, mainly due to the imported parts with unfavorably high exchange rates. In the best scenario and not considering revenue from commercial application, the calculated payback period of the EV is 13years of operation.
Silicon (Si) has been regarded as next-generation anode for high-energy lithium-ion batteries (LIBs) due to its high Li storage capacity (4200 mA h g−1). However, the mechanical degradation and resultant capacity fade critically hinder its practical application. In this regard, we demonstrate that nanocoating of Si spheres with a 3 nm titanium dioxide (TiO2) layer via atomic layer deposition (ALD) can utmostly balance the high conductivity and the good structural stability to improve the cycling stability of Si core material. The resultant sample, Si@TiO2-3 nm core–shell nanospheres, exhibits the best electrochemical performance of all with a highest initial Coulombic efficiency and specific charge capacity retention after 50 cycles at 0.1C (82.39% and 1580.3 mA h g−1). In addition to making full advantage of the ALD technique, we believe that our strategy and comprehension in coating the electrode and the active material could provide a useful pathway towards enhancing Si anode material itself and community of LIBs.
NiO hollow spheres are prepared by heating the NiCl2/resorcinol-formaldehyde (RF) gel in argon at 700°C for 2h, and subsequently in oxygen at 700°C for 2h. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) are employed to characterize the structure and morphology of the as-prepared NiO hollow spheres. These hollow spheres have a diameter of about 2μm, which are composed of NiO particles of about 200nm. The electrochemical properties of these NiO hollow spheres are investigated to determine the reversible capacity and cycling performance as anode materials for lithium-ion batteries, and the advantages of their hollow spherical morphology to the electrochemical performance are discussed.
Herein, we review our latest advancements in nanostructured photoanodes for next generation photovoltaics in general and dye-sensitized solar cells in particular. Bottom-up self-assembly techniques are developed to fabricate large-area 3D nanostructures that enable enhanced charge extraction and light harvesting through optical scattering or photonic crystal effects to improve photocurrent, photovoltage and fill factor. Using generalized techniques to fabricate specialized nanostructures enables specific optoelectronic and physical characteristics like conduction, charge extraction, injection, recombination and light harvesting but also helps improve mechanical flexibility and long-term stability in low cost materials.
A practical semi-empirical battery wear model is proposed for electric vehicle (EV) charging applications. The necessary parameters are investigated for EV charging control from a practical perspective. The proposed battery wear model is based on pervasive experimental cycle life data provided by the manufacturers. The return value of the model directly indicates the wear cost, and thereby, it can be combined with other criteria for multi-objective optimization. As a result, the proposed model is more practically applicable to battery-charging applications than the conventional models. Then, the cost functions are developed for typical vehicle-to-grid (V2G) applications incorporating the battery wear. Based on the developed cost functions, several case studies are performed showing the significance of the battery wear. It is shown through simulation that neglecting the effect of wear in V2G applications may lead to an erroneous result attributed to the exaggerated cost.
The aim of this study was to assess the environmental worries of teacher trainees, and identify their attitudes to protect environment. This was a descriptive field study. The study group was made up of 120 teacher trainees. The data were collected by using open-ended questions developed by the researchers, and were interpreted by making content analysis. At the end of the study, it was understood that the teacher trainees obtained most of the information about environment through internet, TV, and course books. Global warming, earth/air/water pollution, decrease in animal and plant species were the topics which worried the trainees most in terms of environment. It was understood that not to waste, to use recyclable products, and to plant were environmental actions which the trainees had done most.. Moreover, it was figured out that the teacher trainees expressed the human factors were the main culprits of environmental problems.
Using a gel electrolyte for electric double layer capacitors usually encountered a drawback of poor contact between the electrolyte and the electrode surface. A gel electrolyte consisting of poly(ethylene oxide) crosslinked with poly(propylene oxide) as a host, propylene carbonate (PC) as a plasticizer, and LiClO4 as a electrolytic salt was synthesized for double layer capacitors. Diglycidyl ether of bisphenol-A was blended with the polymer precursors to enhance the mechanical properties and increase the internal free volume. This gel electrolyte showed an ionic conductivity as high as 2×10−3 Scm−1 at 25°C and was electrochemically stable over a wide potential range (ca. 5V). By sandwiching this gel-electrolyte film with two activated carbon cloth electrodes (1100m2 g−1 in surface area), we obtained a capacitor with a specific capacitance of 86Fg−1 discharged at 0.5mAcm−2, while the capacitance was 82Fg−1 for a capacitor equipped with a liquid electrolyte of 1M LiClO4/PC. The capacitance decrease with the current density was less significant for the gel-electrolyte capacitor. We found that the less restricted ion diffusion near the electrolyte/electrode interface led to the smaller overall resistance of the gel-electrolyte capacitor. The high performance of the gel-electrolyte capacitor has demonstrated that the developed polymer network not only facilitated ion motion in the electrolyte bulk phase but also gave an intimate contact with the carbon surface. The side chains of the polymer in the amorphous phase could stretch across the boundary layer at the electrolyte/electrode interface to come into contact with the carbon surface, thus improving transport of Li+ ions by the segmental mobility in polymer.
This paper is about the design and implementation of a thermal management of an energy storage system (ESS) for smart grid. It uses refurbished lithium-ion (li-ion) batteries that are disposed from electric vehicles (EVs) as they can hold up to 80% of their initial rated capacity. This system is aimed at prolonging the usable life of li-ion EV batteries by reusing them for energy storage. However, the high value of the internal resistance of refurbished batteries generates more heat and consequently accelerates further their aging process as their operating temperature plays a vital role on their reliability, lifespan, safety and performance. Battery Thermal Management System (BTMS) must keep the operating temperature of the battery pack between −10°C and 40°C in order to achieve good performances and long lifespan. Active BTMS consumes energy from the pack and reduces its available capacity. In order to reduce this adverse impact, this paper presents a novel approach that takes advantage of the non-uniform surface distribution of li-ion battery cell, which results from complex reactions inside the cell. First, li-ion hotspots were identified and found next to the positive and negative tabs. Then, thermoelectric coolers (TECs) are mounted next to the tabs and in the center of the li-ion battery. A control circuit is designed to turn on and off TECs in order to reduce the parasitic power feeding the proposed system, referred to as modular battery thermal management system (MBTMS). Experimental results show the performance of the MBTMS under normal conditions, such as an ambient temperature of 25°C and a discharge rate of C/1 to 2C, and under extreme conditions, such as 40°C and 3C discharge rate. Finally, its performance is compared against a compatible BTMS based on forced air flow. The experimental results show the feasibility of the proposed system.
The aim of this study was to compare the proprioceptive accuracy in the dominant and nondominant lower extremities between early and late stages of adolescence in boys. Participants displaying sexual development consistent with Tanner stages I or II were included in the early adolescent group, and those displaying development consistent with Tanner Stages IV or V were included in the late adolescent group. Proprioception was evaluated using the following 4 tests: one-leg-standing test, a single-limb-hopping test, an active angle-reproduction test, and a passive angle-reproduction test. There were statistically significant differences between the early and late stages of adolescence in nondominant ankles with regard to this single-limb-standing test. There were no statistically significant differences between the early and late adolescent stages, and between dominant and nondominant extremities with regard to the single-limb-hopping test. There were no statistically significant differences between early and late adolescent stages with regard to passive and active ankle plantar- and dorsiflexion position reproduction. Based on these findings, we concluded that sexual maturation categorized by Tanner stage does not affect proprioceptive ability in adolescent individuals. Clinical relevance: This method, as a clinical assessment of detecting deficits in neuromuscular control examined by foot and ankle surgeons and a rehabilitation technique to treat functional instability of the ankle used by physical therapists, might be applied to adolescents. Therefore, clinicians may obtain reliable information from the functional test battery during the assessment of ankle joint performance in adolescents.
The role of the government has rarely been examined in the previous literature on Disruptive Innovation (DI). We present a case study of how government shaped the development trajectory of a DI through both promotional and restrictive policies in the emergence of the electric bike (E-bike) industry in China. We also show how the distinctive nature of DI influenced the strategies of the E-bike firms and how the industry and the institutional environment co-evolved in the process. We believe our study has practical implications for policy makers in making catching-up strategies as well as strategies about the pollution prevention industry and the new energy automobile industry in transition economies.
In research on cognitive plasticity, two training approaches have been established: (1) training of strategies to improve performance in a given task (e.g., encoding strategies to improve episodic memory performance) and (2) training of basic cognitive processes (e.g., working memory, inhibition) that underlie a range of more complex cognitive tasks (e.g., planning) to improve both the training target and the complex transfer tasks. Strategy training aims to compensate or circumvent limitations in underlying processes, while process training attempts to augment or to restore these processes. Although research on both approaches has produced some promising findings, results are still heterogeneous and the impact of most training regimes for everyday life is unknown. We, therefore, discuss recent proposals of training regimes aiming to improve prospective memory (i.e., forming and realizing delayed intentions) as this type of complex cognition is highly relevant for independent living. Furthermore, prospective memory is associated with working memory and executive functions and age-related decline is widely reported. We review initial evidence suggesting that both training regimes (i.e., strategy and/or process training) can successfully be applied to improve prospective memory. Conceptual and methodological implications of the findings for research on age-related prospective memory and for training research in general are discussed.
The main purpose of this study was to determine whether supplemental intake of coenzyme Q10 (CoQ) (ubiquinone-10) or α-tocopherol, either alone or together, could improve brain function of aged mice, as reflected in their cognitive or psychomotor performance. Separate groups of aged mice (24 months) were administered either CoQ (123 mg/kg/day), or α-tocopherol acetate (200 mg/kg/day), or both, or the vehicle (soybean oil) via gavage for a period of 14 weeks. Three weeks following the initiation of these treatments, mice were given a battery of age-sensitive behavioral tests for the assessment of learning, recent memory, and psychomotor function. In a test that required the mice to rapidly identify and remember the correct arm of a T-maze, and to respond preemptively in order to avoid an electric shock, the intake of α-tocopherol plus CoQ resulted in more rapid learning compared to the control group. Learning was not significantly improved in the mice receiving CoQ or α-tocopherol alone. None of the treatments resulted in a significant improvement of psychomotor performance in the old mice. In a separate study, treatment with higher doses of CoQ alone (250 or 500 mg/kg/day) for 14 weeks failed to produce effects comparable to those of the combination of α-tocopherol and CoQ. The apparent interaction of CoQ and α-tocopherol treatments is consistent with the previous suggestion, based on biochemical studies, that coenzyme Q and α-tocopherol act in concert. Overall, the findings suggest that concurrent supplementation of α-tocopherol with CoQ is more likely to be effective as a potential treatment for age-related learning deficits than supplementation with CoQ or α-tocopherol alone.
Carbon has been regarded as one of the most attractive cathode materials for non-aqueous lithium-oxygen batteries due to its excellent conductivity, high specific area, large porosity, and low cost. However, a key disadvantage of carbon electrodes lies in the fact that carbon may react with Li2O2 and electrolyte to form irreversible side products (e.g. Li2CO3) at the active surfaces, leading to a high charge voltage and a short cycling life. In this work, we address this issue by decorating NiO and RuO2 nanoparticles onto carbon surfaces. It is demonstrated that the NiO-RuO2 nanoparticle-decorated carbon electrode not only catalyzes both the oxygen reduction and evolution reactions, but also promotes the decomposition of side products. As a result, the battery fitted with the novel carbon cathode delivers a capacity of 3653 mAh g−1 at a current density of 400 mA g−1, with a charge plateau of 4.01 V. This performance is 440 mV lower than that of the battery fitted with a pristine carbon cathode. The present cathode is also able to operate for 50 cycles without capacity decay at a fixed capacity of 1000 mAh g−1, which is more than twice the cycle number of that of the pristine carbon cathode.
Among the viable positive electrode materials recently proposed for Na-ion secondary batteries, Na2FeP2O7 was investigated thanks to its facile preparation, the use of highly abundant and low cost raw materials, and the highest thermal stability among all others cathode materials. In the present work the electrochemical features of the Na2FeP2O7 are improved by synthesizing a Na2FeP2O7-carbon nanotubes composite with prominent high-rate performances. The material shows a reversible specific capacity of 86 mAh g−1 for 140 cycles at 1C and 68 mAh g−1 at 10C. An in depth investigation about the Na+ diffusion rates inside the material was conducted by electrochemical impedance spectroscopy.
Lithium ion batteries offer an attractive solution for powering electric vehicles due to their relatively high specific energy and specific power, however, the temperature of the batteries greatly affects their performance as well as cycle life. In this work, an empirical equation characterizing the battery's electrical behavior is coupled with a lumped thermal model to analyze the electrical and thermal behavior of the 18650 Lithium Iron Phosphate cell. Under constant current discharging mode, the cell temperature increases with increasing charge/discharge rates. The dynamic behavior of the battery is also analyzed under a Simplified Federal Urban Driving Schedule and it is found that heat generated from the battery during this cycle is negligible. Simulation results are validated with experimental data. The validated single cell model is then extended to study the dynamic behavior of an electric vehicle battery pack. The modeling results predict that more heat is generated on an aggressive US06 driving cycle as compared to UDDS and HWFET cycle. An extensive thermal management system is needed for the electric vehicle battery pack especially during aggressive driving conditions to ensure that the cells are maintained within the desirable operating limits and temperature uniformity is achieved between the cells.
Five 1,1-difluoro-1-alkenes bearing aryl groups are investigated as electrolyte additives for high-charge-voltage lithium ion batteries with an aim to induce favorable solid electrolyte interphase (SEI) formation. Among them, 1,1-difluoro-4-phenylbut-1-ene (DF-1) forms appropriate SEIs on the cathode and anode by its reactions under oxidative and reductive conditions, respectively, which was suggested by linear sweep and cyclic voltammetry. The SEIs formed with the DF-1 containing electrolyte on the cathode and anode were analyzed by X-ray photoelectron spectroscopy and time of flight-secondary ion mass spectrometry, indicating the following: (i) the cathode surface has a LiF-rich layer with unsaturated hydrocarbons, and (ii) the anode surface also has a LiF-rich layer, which probably includes fluoromethylene (CHF) compounds. The formation of the SEIs on both electrodes with DF-1 results in low impedance being maintained, and thus, particularly good cycle performance even at high-charge-voltage.
A foaming process was used to prepare porous polymer membranes (PPMs) based on poly(vinylidene diflouride-co-hexafluoropropylene) copolymer for lithium ion batteries. In this simple process, urea, the foaming agent, was decomposed into gases and was removed at an elevated temperature to get the porous structure within the polymer matrix. When the weight ratio of urea to P(VDF-HFP) is 5:6, the PPM presents the highest porosity, 70.2%, and the prepared gelled polymer electrolyte shows an ionic conductivity up to 1.43×10−3 Scm−1 at room temperature. This provides another way to prepare gelled polymer electrolytes easily for application in rechargeable lithium batteries.