batterydata/paper-abstracts huggingface dataset:
Lithium-sulfur (Li-S) batteries are widely recognized as the most promising next generation energy storage system owing to the incredibly high theoretical energy density and specific capacity. Nevertheless, the practical application of Li-S batteries is hindered by the inevitable “shuttle effect” of the soluble lithium polysulfide, which leads to fast capacity degradation, low coulombic efficiency and severe self-discharge. To address these issues, we propose an ultralight carbon flakes modified separator (CFs@PP) that improves the conductivity and works as an effective polysulfide barrier for high-performance Li-S batteries. The CFs are easily obtained by the direct carbonization of sodium citrate, making it possible for large scale manufacture. With the CFs@PP separator employed, the Li-S battery delivers an initial discharge capacity of 1063 mAh g−1 and retains 683 mAh g−1 after 500 cycles at 0.5C with a low capacity decay rate of 0.071% per cycle. Moreover, great rate performance and small self-discharge are also acquired with the CFs@PP separator applied. The facile preparation of the CFs and the superior electrochemical performance of the CFs@PP separator may promote the commercialization of Li-S batteries.
Electrical stimulation (ES) to manipulate the central (CNS) and peripheral nervous system (PNS) has been explored for decades, recently gaining momentum as bioelectronic medicine advances. The application of ES in vitro to modulate a variety of cellular functions, including regenerative potential, migration, and stem cell fate, are being explored to aid neural degeneration, dysfunction, and injury. This review describes the materials and approaches for the application of ES to the PNS and CNS microenvironments, towards an improved understanding of how ES can be harnessed for beneficial clinical applications. Emphasized are some recent advances in ES, including conductive polymers, methods of charge transfer, impact on neural cells, and a brief overview of alternative methodologies for cellular targeting including magneto, ultrasonic, and optogenetic stimulation. This review will examine how heterogenous cell populations, including neurons, glia, and neural stem cells respond to a wide range of conductive 2D and 3D substrates, stimulation regimes, known mechanisms of response, and how cellular sources impact the response to ES.
Understanding the lithium–silicon alloying behavior is essential for achieving maximum charge capacity in the negative electrodes of lithium-ion batteries. Our atomistic simulations show that in amorphous silicon with a disordered network structure, inserted lithium atoms can find equilibrium positions in the interstices of big rings. Alternatively, lithium is incorporated into the network by the destruction and reformation of smaller rings. These atomic-level mechanisms are characterized by using the network topology measure of ring statistics, which are correlated to the lithiation responses of silicon electrodes. The results reveal the influence of lithium concentrations on the electro-chemical–mechanical behavior of silicon. Implications on the reversibility and dynamics of the lithiation process are discussed.
Paraffin as a phase change material (PCM) is typically used in thermal management of Li-ion batteries. However, the low thermal conductivity of PCMs limits their use in high power devices. Superior thermal conductivity materials are often embedded in PCMs for heat dissipation in the passive thermal management system. In this work, copper fiber/paraffin composite phase change material (CPCM) was prepared based on solid-phase sintering technology. Li-ion batteries in four types of heat dissipation methods (natural wind cooling, filled with pure paraffin, copper foam/paraffin, and copper fiber/paraffin) were tested under different discharging currents. The effect of the porosity of copper fibers was also studied. The result indicates that copper fiber/paraffin CPCM can effectively improve the heat transfer performance and the uniformity of battery temperature within a 2 °C difference. Appropriately increasing the content of copper fiber is favorable to obtain high heat transfer properties of the material. It's predicted that porosity of 90% of copper fiber sintered skeleton offers the best performance of the composite material.
Solar energy is the most promising source of clean, renewable energy and it has the greatest potential of any power source to solve the world's energy problems. However, the problem, is how best to harness this vast amount of solar energy. Nevertheless, even if highly efficient Concentrating Solar Power (CSP) could be made cheaply, there would be considerable change in solar power. This technology is expected to be more efficient and to achieve a manufacturing cost of less than $1/W near future. This paper reviews and elaborates the methodology utilized to design and fabricate the solar dish concentrator and outlines the parameters that can be used to increase the efficiency of solar fraction in parabolic dish concentrator under wet climate environment in Malaysia. The study finally provides ideas to the continually increasing ability of these technologies to concentrate and harness solar energy for electricity production and thus eliminate the growing concern over climate change and how it will hurt the region's environment, human health and economy.
Amorphous iron phosphate (FePO4) was investigated as a cathode material for battery applications using aqueous (lithium hydroxide or potassium hydroxide) electrolytes. Phosphate-based cathode materials are of great interest in lithium batteries which use non-aqueous electrolytes. In order for these materials to be used as cathodes in aqueous electrolytes it is important to understand their reduction/oxidation mechanisms. Potentiostatic and galvanostatic techniques are used to study these mechanisms. X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) have been used to gain insight into the reduction/oxidation behavior of FePO4 cathodes. Our results show that FePO4 undergoes reversible Fe3+/2+ processes of reduction and oxidation in LiOH electrolyte, while using KOH electrolyte this process is found to be irreversible. The lithium intercalation mechanism is identified for LiOH while in the case of KOH electrolyte H reacts to form FeOOH. The Zn|LiOH|FePO4 battery provides a reversible capacity of 65mAh/g. The results indicate the trigonal FePO4 as an attractive host intercalation compound.
Long-term amnesia is a slowly developing form of anterograde amnesia accompanied by retrograde amnesia of variable severity (Kapur, 1996; 1997) often associated with damage to the anterior temporal neocortex and epileptic seizures. The precise neural and functional deficits that underlie this condition are unknown. A patient, JL, who has this condition following a closed-head injury, is described in detail. Her injury caused bilateral anterior temporal neocortex damage that was more extensive on the left and right-sided damage to the perirhinal and orbitofrontal cortices. The hippocampus appeared to be intact bilaterally. Epilepsy developed within two years of JL's injury. Apart from her memory impairments, JL's cognitive functions, including high-level visual perception, attention, semantic memory and executive functions were well preserved. Her memory also seemed well preserved for at least 30 minutes following encoding. The one exception was the patient's relatively greater impairment at difficult visual recognition tests for which verbalization may not have been an effective strategy. This problem may have been caused by JL's right-sided perirhinal and orbitofrontal cortex damage. Her recall and recognition was clearly impaired after a three-week delay. She also showed a retrograde amnesia, which appeared to be milder than her remote post-morbid memory deficit. JL's remote memory was preserved for information first encountered in either the pre- or post-morbid period provided the information had received sufficient rehearsal over long periods of time. Her long-term amnesia may have been caused by anterior temporal neocortex damage, possibly in association with her epileptic seizures. Whether the condition is heterogeneous, involves a deficit in slow consolidation, disruption of unconsolidated memories, or blockage of maintenance or disruption of insufficiently rehearsed memories whether or not these have been slowly consolidated is discussed.
A description is given of a fuel-cell power-supply for mobile phones that operates at room temperature and ambient pressure using liquid methanol and ambient air. The unit is a hybrid system in which a direct methanol fuel-cell (DMFC) and a back-up battery are connected in parallel to meet the power requirements of mobile phones. Electrochemical catalysts for the anode and the cathode of the DMFC are synthesized and Nafion-115 is used as the electrolyte. A 2M methanol solution is filled in the feed reservoir, and the cathode is exposed to ambient air. Eight unit cells, each having 9cm2 of active area, are connected in series in order to raise the output voltage to 2.5–3.9V, which is the typical voltage range for most mobile phones. Also, to simulate the practical application, an electric circuit is included to increase the output voltage of the back-up battery to repeat the charge–discharge cycle. During talk mode, the DMFC supplies 10–50% of the required power and the back-up battery supplies the remainder. In standby mode, the DMFC covers 100% of the required power and charges the back-up battery.
In this study, a metastable form of vanadium dioxide, denoted as VO2(B), has been successfully synthesized under solvothermal condition. However, the as-received VO2(B) suffers from fast capacity fading and poor high-rate performance. In order to overcome these problems, the as-received VO2(B) is solvothermally treated with reduced graphene oxide (rGO) to produce VO2(B)/rGO composite. As a result, the resulting electric conductivity of the VO2(B)/rGO composite is improved to ∼10−4 cm S−1 (from ∼10−7 S cm−1 for the as-received VO2(B)). Electrochemical data of the VO2(B)/rGO composite, tested in both Li and Na cells, shows markedly enhanced electrochemical performance compared to bare VO2(B). The effect of electro-conducting rGO is more evident at high rates.
Stimulating new industries from emerging technologies is central to successful high-tech based economic growth, employment, competition and sustainability in modern market economies. The Taiwanese experiences in developing new technology-based industries (e.g. integrated circuits, personal computers, notebooks, scanners, and TFT LCDs) illustrate some of the ways policy makers can shape the development of emerging technologies into new industries. These ways of actions are manifold, but at least policy attentions to three key mechanisms are critical. These mechanisms encourage partnership in the commercialization process, foster entrepreneurship and venture initiatives in the innovation system, and sustain commercialization and the creation of new firms. The study of Industrial Technology Research Institute in Taiwan on biochips and nanotechnology further shows how the policy makers can build a statutory body to effectively address the functions of three mechanisms as a whole.
In this work, we compare the performance of Li–O2 batteries in pure/dry O2, pure O2 with a relative humidity (RH) of 15% and ambient air with an RH of 50%, and analyze the ambient humidity effect on the reactions in the carbon-based catalytic electrode. Electrochemical investigation indicates that discharge capacities of Li–O2 batteries increased with growth of RH value, but cyclic ability and rate performance are influenced in an opposite way. Ex-situ X-ray diffraction (XRD), Fourier transform-infrared spectrophotometer (FT-IR) and scanning electron microscope (SEM) investigations suggest that ambient humidity affects not only the Li2O2/O2 conversion, LiCO3/CO2 conversion and LiOH formation but also the morphology of discharge products in porous catalytic electrode over charge/discharge cycle. These results may be important for developing Li–air battery.
Oxytocin has numerous prosocial and antipsychotic-like effects in animals. Prosocial effects of acute intranasal oxytocin administration have also been reported in human subjects. We conducted a randomized, placebo-controlled trial testing the effects of twice daily intranasal oxytocin treatment for 14days on psychotic symptoms and social cognition in patients with schizophrenia. PANSS scores declined significantly and several social cognition measures improved significantly or nearly significantly in oxytocin (N=11) but not placebo (N=9) recipients. Our results suggest that, in addition to reducing classic psychotic symptoms, oxytocin may diminish certain social cognition deficits that are not improved by current antipsychotic medications.
The non-aqueous Li-air battery offers the highest theoretical energy density among currently available rechargeable storage units. However, H2O and CO2 in air are viewed as detrimental factors which hinder its performance. Thus, most previous researches focus on the Li-oxygen battery with pure O2 as working atmosphere. The actual influence of ambient air on the cell chemistry has seldom been investigated. Here, we carry out study of the Li-air batteries with tetraethylene glycol dimethyl ether (TEGDME)-based electrolytes and carbon-nanotube-based cathodes operated in ambient air. The cells show the specific capacity as large as 7000mAhg−1 upon the first discharge to 2V and more than 50 cycles when being operated with the capacity cutoff of 500mAhg−1. It is found that the TEGDME-based electrolytes slightly decompose during cell operation. Li2O2 forms during initial discharge and turns Li2CO3 and LiOH owing to its reaction with CO2 and H2O. The lithium anodes become expanded and pulverized after cycles, the problem of which can be relieved by protection with coated polymer layers. These results give essential information that would be helpful for development of the practical Li-air batteries operated in ambient atmosphere.
The present communication reports on the first preparation of porous tubular C/MoS2 nanocomposites using porous anodic aluminum oxide as a template. We further demonstrate the application of such composites as a novel electrode material for supercapacitors. It is found that they can deliver a high capacitance of 210F/g at 1A/g and exhibit excellent long-term cycling stability over 1000 cycles.
Lithium metal attracts growing attention as an ideal anode candidate for next generation lithium battery systems owing to its high capacity, low density, and low working potential. However, the volume expansion of the bulk and dendrite growth on the surface of lithium anode limits its practical application. Herein, we fabricate a composite lithium host featuring both multiple scaled structure and lithiophilic property to address obstacles at both aspects of bulk and surface simultaneously. In which, the multiple scaled structure provides void space to accommodate lithium volume change while zinc and cobalt oxides sites derived from Zeolitic Imidazolate Frameworks can react with lithium and form a stable solid electrolyte interphase, leading to a stable cycling of lithium symmetrical cell for more than 500 cycles with voltage hysteresis of only 88 mV at 2 mA cm−2 and 5 mA h cm−2. Moreover, full cells paired with LiFePO4 cathode can realize 500 cycles with 99.2% capacity retention, showing great potential for practical applications. The excellent electrochemical performance of the composite lithium anode proves the effectiveness of our anode design with multiple scaled structure and lithiophilic feature, which can be also expanded to other metal anodes for batteries.
With the development and popularization of electric vehicles, it is urgent and necessary to develop effective management and diagnosis technology for battery systems. In this work, we design a parallel battery model, according to equivalent circuits of parallel voltage and branch current, to study effects of imbalanced currents on parallel large-format LiFePO4/graphite battery systems. Taking a 60 Ah LiFePO4/graphite battery system manufactured by ATL (Amperex Technology Limited, China) as an example, causes of imbalanced currents in the parallel connection are analyzed using our model, and the associated effect mechanisms on long-term stability of each single battery are examined. Theoretical and experimental results show that continuously increasing imbalanced currents during cycling are mainly responsible for the capacity fade of LiFePO4/graphite parallel batteries. It is thus a good way to avoid fast performance fade of parallel battery systems by suppressing variations of branch currents.
A lithium nickel manganese oxide, O3-Li2/3Ni1/3Mn2/3O2, is synthesized from the precursor, P3-Na2/3Ni1/3Mn2/3O2, by a Na+/Li+ ion exchange reaction using molten salt. Post-heating at 300, 400, 500, 600, and 700 °C is carried out for 5 h in air. The products are characterized by powder XRD, inductively coupled plasma-atomic emission spectroscopy (ICP-AES), SEM, 6Li-magic-angle-spinning-NMR, and electrochemical measurements. The charge/discharge profiles of O3-Li2/3Ni1/3Mn2/3O2, thermally treated at 500 °C, show a high-potential plateau region at 4.8 V. Furthermore, sloping voltage profiles are observed at an average voltage of 3.21 V. An initial discharge capacity of 257 mA h g−1 is obtained between 2.0 and 4.8 V with a current density of 15 mA g−1 at 25 °C. This capacity corresponds to 0.90 electron transfers per formula unit. This study shows that Post-heating of O3-Li2/3Ni1/3Mn2/3O2 is effective to improve its electrochemical properties.
A series of novel organic–inorganic hybrid membranes with special microstructure, based on sulfonated poly (fluorenyl ether ketone) ionomer (SFPEK, IEC=1.92mequiv.g−1) and SiO2 or sulfonic acid group containing SiO2 (SiO2–SO3H), has been successfully designed and prepared for vanadium redox flow battery (VRB) application. The SiO2–SO3H is synthesized by co-condensation of tetraethoxysilane and γ-propyl mercaptotrimethoxysilane via sol–gel process to control the same IEC with neat SPFEK. The hybrid membranes are prepared by simply adding the inorganic particles into the SPFEK solution in N,N′-dimethylacetamide, followed by ultrasonic dispersion, casting and profiled temperature drying process. The morphology is examined by SEM-EDX which is applied to the top surface, bottom surface and cross-section of the hybrid membranes. The water uptake, oxidative stability, thermal property, mechanical property, proton conductivity, VO2+ permeability and single cell performance are investigated in detail in order to understand the relationship between morphology and property of the membranes. All the hybrid membranes show dramatically improved proton selectivity at 20°C and 40°C when compared with Nafion117. The VRB assembled with the SPFEK/3%SiO2 and SPFEK/9%SiO2 membranes exhibit higher coulombic efficiency and average discharge voltage than the VRB assembled with the SPFEK membrane at all the tested current densities.
Energy sustainability and environmental preservation have become worldwide concerns with the many manifestations of climate change and the continually increasing demand for energy. As cities and nations become more technologically advanced, electricity consumption rises to levels that may no longer be manageable if left unattended. The Smart Grid offers an answer to the shift to more sustainable technologies such as distributed generation and microgrids. A general public awareness and adequate attention from potential researchers and policy makers is crucial. This paper presents an overview of the Smart Grid with its general features, functionalities and characteristics. It presents the Smart Grid fundamental and related technologies and have identified the research activities, challenges and issues. It demonstrates how these technologies have shaped the modern electricity grid and continued to evolve and strengthen its role in the better alignment of energy demand and supply. Smart Grid implementation and practices in various locations are also unveiled. Concrete energy policies facilitate Smart Grid initiatives across the nations. Interestingly, Smart Grid practices in different regions barely indicate competition but rather an unbordered community of similar aspirations and shared lessons.
The potentiostatic intermittent titration technique (PITT) is an electroanalytical method that has been widely used to study diffusion of solutes (such as lithium) in electrode materials. Here, we extend the conventional PITT method to account for finite interfacial reaction kinetics and derive analytic equations for electric current under PITT operations. Using the modified PITT, the lithium diffusion coefficient in host materials and the interfacial reaction kinetics can be determined simultaneously. We demonstrate this modified PITT by an example of lithium diffusion in graphite (mesocarbon microbeads, MCMB) and show the improvements of the modified PITT theory over the conventional PITT for investigating the kinetics of electrodes comprising spherical particles.
The industrial production of lithium-sulfur batteries has become a problem, and the core problem of lithium-sulfur batteries lies in the positive electrode materials. This paper is mainly to improve the cathode material of lithium-sulfur batteries. In order to improve the conductivity of the positive electrode of sulfur, to solve the volume expansion of sulfur during discharge, to inhibit the dissolution of polysulfide in the electrolyte and the shuttle effect, this paper improved the high electrochemical performance of lithium-sulfur batteries and promoted the industrialization of lithium-sulfur batteries. Simultaneously, combined with wavelet analysis and transform image processing technology, this paper conducted qualitative analysis on the performance of battery materials, and combined experiments to conduct research and analysis. Experiments show that the method proposed in this study is scientific and can provide theoretical reference for subsequent related research.
The synthesis of lithiated manganese oxides Li x MnO2+δ obtained via a sol–gel process combined with an ion-exchange reaction is reported. The electrochemical performances are strongly dependent on the heat-treatment of the Li-exchanged compound obtained after the ion-exchange procedure. The best results are obtained for the sample heat-treated at 300°C and which corresponds to a mixture of a spinel phase (a=8.16Å) and a lamellar phase. Galvanostatic cycling tests in the potential window 4.2/2V show that a stable capacity of 155mAh/g is achieved after 20 cycles performed at C/20 rate.
Developing advanced electrode materials that deliver high energy at ultra-fast charge and discharge rates are very crucial to meet an increasing large-scale market demand for high power lithium ion batteries (LIBs). A three-dimensional (3D) nanoflower structure is successfully developed in the large-scale synthesis of LiNi1/3Co1/3Mn1/3O2 material for the first time. The fast co-precipitation is the key technique to prepare the nanoflower structure in our method. After heat treatment, the obtained LiNi1/3Co1/3Mn1/3O2 nanoflowers (NL333) pronouncedly present a pristine flower-like nano-architecture and provide fast pathways for the transport of Li-ions and electrons. As a cathode material in a LIB, the prepared NL333 electrode demonstrates an outstanding high-rate capability. Particularly, in a narrow voltage range of 2.7–4.3 V, the discharge capacity at an ultra-fast charge–discharge rate (20C) is up to 126 mAh g−1, which reaches 78% of that at 0.2C, and is much higher than that (i.e., 44.17%) of the traditional bulk LiNi1/3Co1/3Mn1/3O2.