batterydata/paper-abstracts huggingface dataset:
A theoretical analysis is provided to describe the recently proposed ‘convection battery’, wherein electrolyte flow is driven through a battery cell to alter its efficiency and power. Concentrated-solution theory rationalizes the observation that imposition of electrolyte flow parallel to the current through a separator can reduce overpotential losses. Equations are provided that allow this overpotential reduction to be computed in terms of the flow rate, as well as physical properties of the electrolyte and separator. Model results are consistent with earlier experimental observations of alkaline convection batteries. Current-coaxial flows with relatively low rates are found to allow fine-tuned control over limiting currents. Driving electrolyte flow through traditional rechargeable battery cells could facilitate very high charge rates.
A mixture of silicon (Si) and silicon suboxide (SiO x , x <2) phases is prepared from talc by magnesio-thermal reduction and acid etching processes. Talc is a clay mineral composed of hydrated magnesium silicate and is one of the most abundant minerals on earth. The reduced Si/SiO x nanoparticles are found to be porous after acid etching and are closely connected. The Si/SiO x particles are supported on a carbon layer which imparts them with electronic conductivity and improved durability towards stresses associated with the volume change of Si/SiO x during cycling. The structural, physical, and electrochemical properties of these electrodes are analyzed through X-ray diffraction, scanning electron microscopy, Fourier transform-infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, electrochemical impedance spectroscopy and galvanostactic charge-discharge tests. The initial discharge capacity of the carbon-coated Si/SiOx obtained from talc is measured to be 842mAh/g at 1C (1500mA/g) which decreases to 470mAh/g after 300cycles, showing a much higher capacity retention (~55.8%) than pure Si nanoparticles. This superior cycling stability may be attributed to the porous network structure of the magnesio-thermally reduced Si/SiOx and its endurance towards volume changes during cycling.
In this study, highly dispersive spherical Li-rich solid solution (Li1.2Mn0.54Ni0.13Co0.13O2) particles are successfully synthesized by a co-precipitation method. Then these particles are treated with aluminum nitrates ethanol solution at 80°C. The treatment can extract lithium (Li2O) from the Li2MnO3 component in the composite of Li1.2Mn0.54Ni0.13Co0.13O2. Simultaneously, a thin layer of Al2O3 can be precipitated on the surface of the electrode particles via direct thermal decomposition of aluminum nitrates. After treatment, the first-cycle coulombic efficiency of the electrode increases from 72.1% to 93.6%, meanwhile it shows a superior cycling stability at 100mAg−1 with a discharge capacity of around 220mAhg−1 and retention of 92.5% after 100 cycles, which is much higher than that of the pristine electrode (83.2%). Even at a high current density of 2Ag−1 (10C), the discharge capacity could still achieve and well maintain as high as 140mAhg−1.
Topology control can enhance energy efficiency and prolong network lifetime for wireless sensor networks. Several studies that attempted to solve the topology control problem focused only on topology construction or maintenance. This work designs a novel distributed and reliable energy-efficient topology control (RETC) algorithm for topology construction and maintenance in real application environments. Particularly, many intermittent links and accidents may result in packet loss. A reliable topology can ensure connectivity and energy efficiency, prolonging network lifetime. Thus, in the topology construction phase, a reliable topology is generated to increase network reachable probability. In the topology maintenance phase, this work applies a novel dynamic topology maintenance scheme to balance energy consumption using a multi-level energy threshold. This topology maintenance scheme can trigger the topology construction algorithm to build a new network topology with high reachable probability when needed. Experimental results demonstrate the superiority of the RETC algorithm in terms of average energy consumption and network lifetime.
Purpose The aim in this study was to examine early speech perception outcomes in Mandarin-speaking children during the first year of cochlear implant (CI) use. Method A hierarchical early speech perception battery was administered to 80 children before and 3, 6, and 12 months after implantation. Demographic information was obtained to evaluate its relationship with these outcomes. Results Regardless of dialect exposure and whether a hearing aid was trialed before implantation, implant recipients were able to attain similar pre-lingual auditory skills after 12 months of CI use. Children speaking Mandarin developed early Mandarin speech perception faster than those with greater exposure to other Chinese dialects. In addition, children with better pre-implant hearing levels and younger age at implantation attained significantly better speech perception scores after 12 months of CI use. Better pre-implant hearing levels and higher maternal education level were also associated with a significantly steeper growth in early speech perception ability. Conclusions Mandarin-speaking children with CIs are able to attain early speech perception results comparable to those of their English-speaking counterparts. In addition, consistent single language input via CI probably enhances early speech perception development at least during the first-year of CI use.
Polyaniline (PANI) films doped with Ni2+ (PANI/Ni2+) were synthesized by cyclic voltammetry (CV) on stainless steel (SS) substrates in 0.2mol/L aniline (An) and 0.5mol/L sulfuric acid (H2SO4) electrolyte with various concentration of nickel sulfate (NiSO4). The structure and morphology of PANI/Ni2+ films were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) techniques. The electrochemical properties of PANI/Ni2+ films were investigated by cyclic voltammetry, galvanostatic charge–discharge test and electrochemical impedance spectroscopy (EIS) in 0.5mol/L H2SO4 electrolyte in three-electrode system. The results suggest that the growth rate of PANI was greatly increased, which may arise from the interactions between PANI chain and Ni2+. The PANI/Ni2+ films show a larger specific capacitance of 658.3F/g at a current density of 5mA/cm2 and lower resistance compared with the pure PANI film. The results indicate that the PANI/Ni2+ films are promising material for supercapacitors.
This paper presents a techno-economic analysis of fuel-cell-based auxiliary power units (APUs), with emphasis on applications in the trucking industry and the military. The APU system is intended to reduce the need for discretionary idling of diesel engines or gas turbines. The analysis considers the options for on-board fuel processing of diesel and compares the two leading fuel cell contenders for automotive APU applications: proton exchange membrane fuel cell and solid oxide fuel cell. As options for on-board diesel reforming, partial oxidation and auto-thermal reforming are considered. Finally, using estimated and projected efficiency data, fuel consumption patterns, capital investment, and operating costs of fuel-cell APUs, an economic evaluation of diesel-based APUs is presented, with emphasis on break-even periods as a function of fuel cost, investment cost, idling time, and idling efficiency. The analysis shows that within the range of parameters studied, there are many conditions where deployment of an SOFC-based APU is economically viable. Our analysis indicates that at an APU system cost of $ 100kW−1, the economic break-even period is within 1 year for almost the entire range of conditions. At $ 500kW−1 investment cost, a 2-year break-even period is possible except for the lowest end of the fuel consumption range considered. However, if the APU investment cost is $ 3000kW−1, break-even would only be possible at the highest fuel consumption scenarios. For Abram tanks, even at typical land delivered fuel costs, a 2-year break-even period is possible for APU investment costs as high as $ 1100kW−1.
Owing to the high theoretical capacity, molybdenum (Mo)-based materials are promising as high-performance anode for lithium-ion batteries (LIBs). Therefore, Y2(MoO4)3 is investigated as anode candidate for the first time in this work. Moreover, in an attempt to improve ionic diffusivity and capacity retention of Y2(MoO4)3, molybdenum-based Y2(MoO4)3 nanowires are successfully formed by a feasible electrospinning method. And the morphologies of as-prepared sample are observed by scanning electron microscope (SEM), transmission electron microscope (TEM) and high-resolution transmission electron microscope (HRTEM). Herein, the Y2(MoO4)3 nanowires show a remarkable charge specific capacity of 480.1mAhg−1 with 67.1% capacity retention at 100mAg−1 after 100cycles. While the capacity retention of Y2(MoO4)3 micro-particles is only 24.4% under the same conditions. Besides, ex-situ X-ray diffraction (XRD), ex-situ TEM and ex-situ X-ray photoelectron spectrometer (XPS) tests are carried to study lithium storage reaction of Y2(MoO4)3 upon the charge/discharge reactions. The results confirm that the Y2(MoO4)3 undergoes a typical conversion reaction, accompanied by the irreversible particle pulverization of structure.
Even though health-related quality of life (HRQOL) is considered an important component of bariatric surgery outcome, there is a lack of HRQOL measures relevant for preoperative and postoperative patients. The objective of the current study was to develop a new instrument assessing HRQOL prior to and following bariatric surgery, entitled Quality of Life for Obesity Surgery (QOLOS) Questionnaire.
The paper showcases the possible application of social media analytics in new product development (NPD). It compares users’ emotions before and after the launch of three new products in the market—a pizza, a car and a smart phone—for possible inputs for NPD. The user-generated content offers an alternative to conventional survey data and is cross-cultural in nature, relatively inexpensive and provides real-time information about user behaviour. A total of 302,632 tweets that mentioned the three new products before and after the launch were collected and analysed. Sentiment analysis of the tweets from two time periods was conducted and compared. The users’ responses to the pre- and post-launch of three products vary. The dissatisfaction with the new products represented by negative emotions aligns with the market performance. In the pre-launch period, trust and joy were more common for pizza, joy was more common for the car, and trust was more common for the phone. In the post-launch period, anger and disgust were more common for pizza, joy and trust were more common for the car, and joy was more common for only one aspect of the phone. Further analysis showed that for the car and the phone, firms need to focus on user attitudes towards product attributes, whereas for pizza, firms should concentrate on physiological changes, i.e., changes in product attributes, service and promotional sides. By using the proposed alternative approach, businesses can obtain real-time feedback about the expectations and experiences of the new products. The NPD process can be adjusted accordingly.
Battery charging controllers design and application is a growing industry direction. Fast and efficient charging of battery packs is a problem which is difficult and often expensive to solve using conventional techniques. The majority of existing works on intelligent charging systems are based on expert knowledge and heuristics. Not all features of the desired charging behavior can be attained by the hard-wired logic implemented by expert generated rules. Because the battery charging is a highly dynamic process and the chemical technology a battery uses varies significantly for different battery types, data mining technique can be of real importance for extracting the charging rules from the large databases, especially when the charging logic is to be continuously changed during the life of the battery dependent on the type and characteristics of the battery and utilization conditions. In this paper we use soft computing-based data mining technique for extraction of control rules for effective and fast battery charging process. The obtained rules were used for NiCd battery charging. The comparative performance evaluation was done among the existing charging control methods and the proposed system, which demonstrated a significant increase of performance (minimum charging time and minimum overheating) using the soft computing-based approach.
Despite the agency perspective of corporate tax avoidance, there is little empirical evidence that managers do extract rents derived from aggressive tax practices. This study investigates the association between tax aggressiveness and managerial rent extraction by focusing on informed insider trading, a self-serving action with an unambiguous impact on insiders’ personal wealth and representing the most direct channel through which managers expropriate outside shareholders. We find that insiders at firms more aggressive in tax avoidance gain significantly higher returns from insider purchases than insiders in less aggressive firms and this outperformance results from trading on future earnings news. We also find that insiders under the cover of aggressive tax practices more likely trade on bad news through insider sales and gain more from these trades. The overall evidence is consistent with aggressive tax planning serving managerial interests through gainfully exploiting private information and extracting rents from uninformed shareholders.
A COX-free 1 kW-class hydrogen power pack fueled by liquid ammonia is presented. For applications in a practical-scale hydrogen production system in conjunction with a polymer electrolyte membrane fuel cell, Ru catalysts supported on La-doped alumina (Ru/La(x)-Al2O3) were pelletized by varying the lanthanum doping content (x mol%) to control catalytic activities. An optimized Ru(1.06 wt%)/La(20)-Al2O3 pellet catalyst presents a >99.7% conversion efficiency at 500 °C under a gas hourly space velocity of 5000 mL gcat −1 h−1. Various materials were screened to remove residual ammonia from the product stream, and the X zeolite was chosen as a highly capable adsorbent. Based on the synthesized catalyst and screened adsorbent, a power pack consisting of a dehydrogenation reactor, an adsorbent tower, and a 1 kW-class polymer electrolyte membrane fuel cell was designed and manufactured. The as-integrated system can convert 9 L min−1 of ammonia into 13.4 L min−1 of hydrogen, powering a 1 kW-class fuel-cell continuously for >2 h without any performance degradation. To achieve autothermal and COX-free operations, heat required for ammonia dehydrogenation was provided by unutilized hydrogen from the fuel cell, drastically increasing the overall efficiency of the system to >49% while removing the external heat source, isobutane. Finally, a drone tethered to the system was operated, demonstrating the feasibility of an elongated flight time of >4 h, much longer than 14 min with Li-polymer battery loaded on the drone. The system is expected to meet the United States Department of Energy’s 2020 gravimetric and volumetric hydrogen storage targets of 4.5 wt% and 30 gH2 L−1 at system weights of 43 kg and 50 kg, respectively.
We present a layered-carbon/PbSO4 composite additive for the negative active material (NAM) of lead-acid batteries to improve their high rate charge/discharge performance. The layered-carbon/PbSO4 composite, consisting of graphene-like two-dimensional carbon decorated with fine PbSO4 particles, is prepared by a simple chemical vapor deposition (CVD) method and a subsequent ion exchange process. In the synthesis process, potassium carbonate functions as template to promote the generation of layered carbon sheets in CVD process and as template in ion exchange process to in situ produce PbSO4 nanoparticles. The composite can effectively enhance the electronic conductivity and the ionic conductivity of NAM, and resist the tendency to sulfation during high-rate partial-state-of-charge (HRPSoC) operation. Moreover, the PbSO4 deposits on the layered-carbon can not only make the carbonaceous additive be uniformly mixed with the NAM, but also inhibit the hydrogen evolution of the layered-carbon. As a result, the specific capacity, rate performance, and HRPSoC cycling performance of the NAM are significantly enhanced. The NAM with 2 wt% composite additive (the content of layered-carbon in NAM is 0.1 wt%) delivers a high initial specific discharge capacity of 160 mAh g−1 at 0.1 C rate, and 61 mAh g−1 at a high rate of 10 C rate, which is 30% higher than that of the Ref one. The cell with composite additives has achieved a HRPSoC cycle life of 160,000 cycles, which is 3 times longer than the Ref cell.
A high-performance composite membrane for vanadium redox flow battery (VRB) consisting of ZrO2 nanotubes (ZrNT) and perfluorosulfonic acid (Nafion) was fabricated. The VRB operated with a composite (Nafion-ZrNT) membrane showed the improved ion-selectivity (ratio of proton conductivity to permeability), low self-discharge rate, high discharge capacity and high energy efficiency in comparison with a pristine commercial Nafion-117 membrane. The incorporation of zirconium oxide nanotubes in the Nafion matrix exhibits high proton conductivity (95.2 mS cm−1) and high oxidative stability (99.9%). The Nafion-ZrNT composite membrane exhibited low vanadium ion permeability (3.2 × 10−9 cm2 min−1) and superior ion selectivity (2.95 × 107 S min cm−3). The VRB constructed with a Nafion-ZrNT composite membrane has lower self-discharge rate maintaining an open-circuit voltage of 1.3 V for 330 h relative to a pristine Nafion membrane (29 h). The discharge capacity of Nafion-ZrNT membrane (987 mAh) was 3.5-times higher than Nafion-117 membrane (280 mAh) after 100 charge-discharge cycles. These superior properties resulted in higher coulombic and voltage efficiencies with Nafion-ZrNT membranes compared to VRB with Nafion-117 membrane at a 40 mA cm−2 current density.
Garnet-type solid-state electrolytes (SSEs) are very promising due to their high ionic conductivities at room temperature and high stability against Li metal. However, the poor garnet/Li interfacial contact caused by Li2CO3 surface contaminant can lead to lithium dendrite growth and the performance decay of solid-state batteries (SSBs), which still hinders their practical application. Herein, a universal and simple method of rapid acid treatment is proposed to perfectly remove the surface Li2CO3 and retrieve a lithiophilic SSE surface. The SSE/Li interfacial resistance dramatically decreases from 940 Ω cm2 to 26 Ω cm2 at 30 °C. The acid treated garnet-SSE pellets exhibit an interfacial resistance comparable to the pellets with various surface coatings. In addition, the intrinsic garnet/Li interface remains stable during cycling, which enables the Li symmetric cells continuously cycle over 700 h under 0.2 mA cm−2 at 30 °C. And the LiFePO4/Li and LiCoO2/Li cells with acid treated garnet-SSE show excellent cycle and rate performances after eliminating the surface contaminant. These results indicate that rapid acid treatment not only guides a new understanding for an intrinsic garnet/Li interface but also is a simple and high-efficiency strategy to well address the interfacial issue for SSBs.
Nanoscale cobalt hydroxide (Co(OH)2) particles are fabricated by electrodeposition on three-dimensional nickel/silicon microchannel plates (Ni/Si-MCPs) as the active electrode materials on the surface and sidewall of the Ni/Si-MCPs for miniature supercapacitors. The relationship among the electrodeposition time, morphology, formation mechanism of Co(OH)2 nanostructure, and capacitor performance is studied. Using an optimal electrodeposition time of 6min, the Co(OH)2 supercapacitor has a capacitance of 697.56Fg−1 (5.72Fcm−2) at 2mAcm−2 and the retention ratio is 91.20% after 2500 cycles. The large areal capacitance and excellent rate capability can be attributed to the unique 3D ordered porous architecture which facilitates electron and ion transport, enlarges the liquid-solid interfacial area, and enhances the utilization efficiency of the active materials. Meanwhile, the weight and size of the device are reduced. By using the Co(OH)2/Ni/Si-MCPs electrode as the positive electrode and CNTs/nickel foam (CNTs/NF) as the negative electrode, the device assembled with CR2025 batteries exhibits high energy density (38.39Whkg−1), high power density (5400Wkg−1 at 9.67Whkg−1), and stable power characteristic (2000 times with 80.63% retention). After charging each supercapacitor for 10s, the device can power a 5mm diameter light-emitting diode (LED) with different colors efficiently, for example, a blue LED for 20min.
We demonstrate a minimal-architecture zinc–bromine battery that eliminates the expensive components in traditional systems. The result is a single-chamber, membrane-free design that operates stably with >90% coulombic and >60% energy efficiencies for over 1000 cycles. It can achieve nearly 9 W h L−1 with a cost of <$100 per kWh at-scale.
In this work we report proof-of-concept of a novel redox flow battery consisting of a solid oxide electrochemical cell (SOEC) integrated with a redox-cycle unit. The charge/discharge characteristics were explicitly observed by operating between fuel cell and electrolysis modes of the SOEC along with “in-battery” generation and storage of H2 realized by an in situ closed-loop reversible steam-metal reaction in the redox-cycle unit. With Fe/FeO as the redox materials, the new storage battery can produce an energy capacity of 348 Wh/kg-Fe and round-trip efficiency of 91.5% over twenty stable charge/discharge cycles. This excellent performance combined with robustness, environmental friendliness and sustainability promise the new battery to be a transformational energy storage device for grid application.
Silicon is being investigated extensively as an anodic material for next-generation lithium ion batteries for portable energy storage and electric vehicles. However, the large changes in volume during cycling lead to the breakdown of the conductive network in Si anodes and the formation of an unstable solid-electrolyte interface, resulting in capacity fading. Here, we demonstrate nanoparticles with a Si@Mn22.6Si5.4C4@C double-shell structure and the formation of self-organized Si-Mn-C nanocomposite anodes during the lithiation/delithiation process. The anode consists of amorphous Si particles less than 10 nm in diameter and separated by an interconnected conductive/buffer network, which exhibits excellent charge transfer kinetics and charge/discharge performances. A stable specific capacity of 1100 mAh·g−1 at 100 mA·g−1 and a coulombic efficiency of 99.2% after 30 cycles are achieved. Additionally, a rate capacity of 343 mAh·g−1 and a coulombic efficiency of 99.4% at 12000 mA·g−1 are also attainable. Owing to its simplicity and applicability, this strategy for improving electrode performance paves a way for the development of high-performance Si-based anodic materials for lithium ion batteries.