batterydata/paper-abstracts huggingface dataset:
Supercapacitors (SCs) based on representative electrochemical electrode materials were assembled and artificial seawater has been proposed as an electrolyte for application in supercapacitor devices for the first time. Seawater is an eco-friendly and unlimited resource and its use as an electrolyte is an entirely new concept for SCs systems. Partially graphitized N-doped porous carbon, MnO2/polypyrrole composite, and Fe2O3 nanosheets were prepared to investigate the electrocapacitive properties of active materials in artificial seawater electrolyte. Furthermore, the aforementioned electrode materials were utilized to fabricate SC devices as the artificial seawater-based supercapacitors. More importantly, long-term cycling tests revealed that carbon-based SC devices showed much higher cycling stability than the other types of SC devices with the former having a high potential for practical application.
A series of Ni(OH)2/Co(OH)2 core/shell nanoplatelets with varying shell thickness (0.5–4.1 nm) are systematically investigated with a combination of scanning electron microscopy (SEM) with energy dispersive x-ray analysis (EDX), x-ray diffraction (XRD), in situ and ex situ x-ray absorption fine structure spectroscopy (XAFS), and electrochemical tests. Structure-properties correlations reveal that electrochemical behavior and reversibility of Co(OH)2 redox conversion depends non-linearly on the average shell thickness, with the best performance (99.6% of theoretical capacity of the composite material, 10% improvement over the performance of pristine Ni(OH)2 nanoparticles) is achieved at shell thickness of 1.9 ± 0.3 nm. Two fundamental phenomena are suggested to be responsible for the superior performance: templated shell deposition and galvanic coupling of core and shell materials. Homogeneous deposition of the shell is confirmed with XRD, SEM and EDX, while lattice templating effect was suggested from XAFS results showing that Co-M and Co-O distances are close to those of the Ni(OH)2 lattice in thin shells and shift gradually towards values of bulk Co(OH)2 as the shell thickness increases. From a combination of electrochemical and structural characterization of these composite nanomaterials, including in situ XAFS, galvanic coupling between the shell and core is proposed as a material activation mechanism, which explains the limited reversibility of the Co(II)/Co(III) oxidation in some cases. Proposed performance enhancement mechanisms are applicable for design of other core/shell electrode materials.
Observation and cutting of DNA molecules at intended positions permit several new experimental methods that are completely different from conventional molecular biology methods; therefore several cutting methods have been proposed and studied. In this paper, a new cutting method for a DNA molecule by localizing the activity of a restriction enzyme is presented. Since most restriction enzymes require magnesium ions for their activation, local restriction enzyme activity can be controlled by the local concentration of magnesium ions. Applying a direct current (dc) voltage to a needle electrode of metallic magnesium made it possible to control the local magnesium ion concentration at the tip of the needle. The restriction enzyme was activated only when magnesium ions were electrochemically supplied.
In this study, we present a new strategy on controlling the interaction between the Li2O2-catalyst interfaces through improving the affinity of catalyst surface towards Li2O2 molecules. A seed-mediated growth approach has been developed to synthesize Pt nanosheets on the stainless steel mesh using Fe as the seed. We further grow a uniform layer of metallic Cu nanoparticles on Pt nanosheets surface through electrochemical deposition. The Cu is converted to CuO by exposing it to air under ambient condition. Such strategy has effectively solved the problem of non-uniform deposition of CuO on Pt surface that arises from the poor interaction of oxides on metals. By converting the oxide-on-metal to metal-on-metal system, a relatively uniform of CuO can be successfully deposited on Pt nanosheets. The CuO on Pt provides multiple nucleation sites on the surface of the cathode, which facilitates the formation of Li2O2 thin layer in the discharge cycle. This process plays a crucial role in achieving a high round-trip efficiency of 88%, reversible specific capacity of 1648 mAh g−1 (683 mAh g−1 with respect to the total electrode mass including Li2O2) at 100 mA g−1 and maintains capacity retention of 98% during the 60th cycle at a high current density of 1 A g−1.
There are increasing concerns that physical material constraints threaten energy security and the growth of emerging technologies. Traditional approaches to quantify material criticality utilize single-score metrics which are narrowly focused on physical scarcity and often lead to command-and-control policies. However, a broader definition of criticality that goes beyond physical scarcity to include sustainability metrics e.g. embodied energy, political instability, economic value can provide policymakers with a more comprehensive perspective of the complex and highly interconnected relationships between indicators. We use the case of solar photovoltaic materials to demonstrate the challenges and opportunities in critical materials policy and indicator choices. For silicon-based and thin-film photovoltaics in particular, Ge, Pt, As, In, Sn and Ag were found to be the most critical relative to the 17 materials studied. Multi-metric analysis for these materials reveals tradeoffs that suggest friction between sustainable economics, political stability of supply, and environmental quality objectives.
Recent research results confirm the importance of structural surface features of cathode materials for their electrochemical performance. Modification by coating is an important method to achieve improved electrochemical performance, and the latest progress was reviewed here. When the surface of cathode materials including LiCoO2, LiNiO2, LiMn2O4 and LiMnO2 is coated with oxides such as MgO, Al2O3, SiO2, TiO2, ZnO, SnO2, ZrO2, Li2O·2B2O3-glass and other materials, the coatings prevent the direct contact with the electrolyte solution, suppress phase transition, improve the structural stability, and decrease the disorder of cations in crystal sites. As a result, side reactions and heat generation during cycling are decreased. Accompanying actions such as suppression of Mn2+ dissolution, increase in conductivity and removal of HF in electrolyte solutions have been observed. Consequently, marked improvement of electrochemical performance of electrode materials including reversible capacity, coulomb efficiency in the first cycle, cycling behavior, rate capability and overcharge tolerance has been achieved. In conclusion, further directions are suggested for the surface modification of electrode materials. With further understanding of the effects of the surface structure of cathode materials on lithium intercalation and de-intercalation, better and/or cheaper cathode materials from surface modification will come up in the near future.
A detailed analysis of potential versus time measurements at galvanostatic charge/discharge conditions (external current change from −1 to +1 mA cm−2) for two La–Ni alloys in Ar-saturated 0.1 M KOH solution is presented. It is shown that passivation of the electrodes does not affect the potential jump as a result of current switching over. The value of potential jump allows to calculate the exchange current density for H2O/H2 system on the tested material. Anodic potential of the hydrogenated electrode (at ia = const) linearly increases with logarithm of time which allows to evaluate precisely time necessary for oxidation of hydrogen absorbed during cathodic charging. The method described enables to determine effectiveness of hydrogen absorption by materials applied for negative electrodes of NiMH batteries.
The increasing demand for real-time applications in Wireless Sensor Networks (WSNs) has made the Quality of Service (QoS) based communication protocols an interesting and hot research topic. Satisfying Quality of Service (QoS) requirements (e.g. bandwidth and delay constraints) for the different QoS based applications of WSNs raises significant challenges. More precisely, the networking protocols need to cope up with energy constraints, while providing precise QoS guarantee. Therefore, enabling QoS applications in sensor networks requires energy and QoS awareness in different layers of the protocol stack. In many of these applications (such as multimedia applications, or real-time and mission critical applications), the network traffic is mixed of delay sensitive and delay tolerant traffic. Hence, QoS routing becomes an important issue. In this paper, we propose an Energy Efficient and QoS aware multipath routing protocol (abbreviated shortly as EQSR) that maximizes the network lifetime through balancing energy consumption across multiple nodes, uses the concept of service differentiation to allow delay sensitive traffic to reach the sink node within an acceptable delay, reduces the end to end delay through spreading out the traffic across multiple paths, and increases the throughput through introducing data redundancy. EQSR uses the residual energy, node available buffer size, and Signal-to-Noise Ratio (SNR) to predict the best next hop through the paths construction phase. Based on the concept of service differentiation, EQSR protocol employs a queuing model to handle both real-time and non-real-time traffic. By means of simulations, we evaluate and compare the performance of our routing protocol with the MCMP (Multi-Constraint Multi-Path) routing protocol. Simulation results have shown that our protocol achieves lower average delay, more energy savings, and higher packet delivery ratio than the MCMP protocol.
In battery technology and electrochemical investigations, it is common to record impedance spectra to specific states (SoC, SoH, temperature, etc.). It is possible to determine appropriate parameters of the battery cell and assign them to the anode and cathode by a specifically selected electrical equivalent circuit diagram. A problem that arises here is that a statement about the reliability of the separation from the entire cell behavior is limited. By measuring the individual spectra of the anode and cathode through a 3-electrode cell and a subsequent single fitting it can be shown how valid the separation is. This Contribution aims to investigate an electrical model that depicts the separation of anode and cathode made of porous active materials.
Hydrogen produced from water and renewable energy could fuel a large fleet of proton-exchange-fuel-cell vehicles in the future. However, the dependence on expensive Pt-based electrocatalysts in such fuel cells remains a major obstacle for a widespread deployment of this technology. One solution to overcome this predicament is to reduce the Pt content by a factor of ten by replacing the Pt-based catalysts with non-precious metal catalysts at the oxygen-reducing cathode. Fe- and Co-based electrocatalysts for this reaction have been studied for over 50 years, but they were insufficiently active for the high efficiency and power density needed for transportation fuel cells. Recently, several breakthroughs occurred that have increased the activity and durability of non-precious metal catalysts (NPMCs), which can now be regarded as potential competitors to Pt-based catalysts. This review focuses on the new synthesis methods that have led to these breakthroughs. A modeling analysis is also conducted to analyze the improvements required from NPMC-based cathodes to match the performance of Pt-based cathodes, even at high current density. While no further breakthrough in volume-specific activity of NPMCs is required, incremental improvements of the volume-specific activity and effective protonic conductivity within the fuel-cell cathode are necessary. Regarding durability, NPMCs with the best combination of durability and activity result in ca. 3 times lower fuel cell performance than the most active NPMCs at 0.80 V. Thus, major tasks will be to combine durability with higher activity, and also improve durability at cell voltages greater than 0.60 V.
Background Deep brain stimulation (DBS) is routinely used as a treatment for treatment-refractory Parkinson's disease and has recently been proposed for psychiatric disorders such as Tourette syndrome (TS), obsessive-compulsive disorder (OCD) and major depressive disorder (MDD). Although cognitive deterioration has repeatedly been shown in patients with Parkinson's disease following DBS, the impact of DBS on cognitive functioning in psychiatric patients has not yet been reviewed. Objective Reviewing the available literature on cognitive functioning following DBS in psychiatric patients. Methods A systematic literature search in PubMed, EMBASE and Web of Science, last updated in September 2012, found 1470 papers. Abstracts were scrutinized and 26 studies examining cognitive functioning of psychiatric patients following DBS were included on basis of predetermined inclusion criteria. Results Twenty-six studies reported cognitive functioning of 130 psychiatric patients following DBS (37 TS patients, 56 OCD patients, 28 MDD patients, 6 patients with Alzheimer's disease, and 3 patients with other disorders). None of the studies reported substantial cognitive decline following DBS. On the contrary, 13 studies reported cognitive improvement following DBS. Conclusion Preliminary results suggest that DBS in psychiatric disorders does not lead to cognitive decline. In selected cases cognitive functioning was improved following DBS. However, cognitive improvement cannot be conclusively attributed to DBS since studies are hampered by serious limitations. We discuss the outcomes in light of these limitations and offer suggestions for future work.
Silicon is a promising negative electrode material candidate for lithium-ion thin-film batteries because of its very high theoretical storage capacity. Assuming full conversion of Si into Li15Si4, a theoretical capacity of 3579mAhg−1 or 8303mAhcm−3 is expected. However, the interaction between silicon thin-film electrodes and various electrolytes (both liquid and solid) is, up until now, not well understood. The interface between the electrode and electrolyte plays a crucial role in the Li-(de)insertion reaction as here the actual charge transfer reaction takes places. To this end, some important issues on the activation of the electrode/electrolyte interface will be addressed in this paper. Moreover, new results on the temperature dependence of the charge transfer kinetics of evaporated silicon thin-film electrodes combined with four different liquid and solid electrolytes will be presented.
This paper discusses the electrochemical behaviors of worm-like mesoporous carbon obtained in 1.0 mol L−1 LiClO4/ethylene carbonate + dimethyl carbonate solution. The capacitance for nanoporous carbon system advances up to 147 F g−1 and a wide voltage window (2.5 V) for three electrode system was achieved. The specific energy and specific power reach as high as 127.6 Wh kg−1 and 5.0 kW kg−1. These results show that worm-like mesoporous carbon can be used for high energy density and power density non-aqueous electrolyte supercapacitors.
Spherical (Ni0.5Mn0.5)(OH)2 with different secondary particle size (3μm, 10μm in diameter) was synthesized by co-precipitation method. Mixture of the prepared hydroxide and lithium hydroxide was calcined at 950°C for 20h in air. X-ray diffraction patterns revealed that the prepared material had a typical layered structure with R 3 ¯ m space group. Spherical morphologies with mono-dispersed powders were observed by scanning electron microscopy. It was found that the layered Li[Ni0.5Mn0.5]O2 delivered an initial discharge capacity of 148mAhg−1 (3.0–4.3V) though the particle sizes were different. Li[Ni0.5Mn0.5]O2 having smaller particle size (3μm) showed improved area specific impedance due to the reduced Li+ diffusion path, compared with that of Li[Ni0.5Mn0.5]O2 possessing larger particle size (10μm). Although the Li[Ni0.5Mn0.5]O2 (3μm) was electrochemically delithiated to Li0.39[Ni0.5Mn0.5]O2, the resulting exothermic onset temperature was around 295°C, of which the value is significantly higher than that of highly delithiated Li1−δ CoO2 (∼180°C).
Conventional Li-ion batteries are severely limited in high temperature applications mainly due to the poor thermal stability of the separator membrane (shrinkage/shutdown) and electrolyte decomposition in the full-cell. We have demonstrated a high temperature Li-ion system capable of good rate performance from 20 to 120 °C, well beyond the typical 60 °C limit of traditional Li-ion batteries. We have developed a printable and highly flexible Al2O3-poly(vinylidene fluoride) nanoporous separator membrane (Pyrolux™) infiltrated with a carefully designed high boiling point lithium bis(oxoalato)borate-based (LiBOB) liquid electrolyte. This unique electrolyte/membrane combination can offer a substantial safety advantage over conventional polyolefin separators embedded with liquid electrolyte, such as reduced flammability and enhanced dimensional stability at high temperature. Li//LiFePO4 and Li//graphite half-cells were tested at 120 °C and achieved reversible capacities of 155 and 340 mA h/g, respectively, with Coulombic efficiencies (CEs) > 99.4%. To date, reports on high temperature Li-ion full-cells have been limited mainly due to a combination of poor thermal stability of the separator membrane, accelerated side reactions, and solid-electrolyte interphase reformation. By utilizing our membrane and electrolyte, LiFePO4//graphite full-cells were successfully demonstrated for the first time at 120 °C with excellent cyclability, representing a major step forward in the development of high temperature Li-ion batteries.
A number of cathodes are being considered for the next generation of lithium ion batteries to replace the expensive LiCoO2 presently used. Besides the layered oxides, such as LiNi y Mn y Co1−2y O2, a leading candidate is lithium iron phosphate with the olivine structure. Although this material is inherently low cost, a manufacturing process that produces electrochemically active LiFePO4 at a low cost is also required. Hydrothermal reactions are one such possibility. A number of pure phosphates have been prepared using this technique, including LiFePO4, LiMnPO4 and LiCoPO4; this method has also successfully produced mixed metal phosphates, such as LiFe0.33Mn0.33Co0.33PO4. Ascorbic acid was found to be better than hydrazine or sugar at preventing the formation of ferric ions in aqueous media. When conductive carbons are added to the reaction medium excellent electrochemical behavior is observed.
This study addresses the impact of an actual drive pattern on the sizing and cost of a battery pack for a plug-in hybrid electric two-wheeler. To estimate the daily average travel distance in fixing the all-electric range of two wheelers, a study conducted in Coimbatore city is presented. A MATLAB simulation model developed for estimating the energy and power requirements in an all-electric strategy using an Indian driving cycle (IDC) and a real-world driving pattern are discussed. The simulation results reveal the impact of the real-world driving pattern on energy consumption and also the influence of all-electric range in sizing the battery pack. To validate the results, a plug-in hybrid electric two-wheeler developed by modifying a standard two-wheeler has been tested on the road with the help of the IDC simulator kit. An annual battery cost comparison shows that nickel–metal-hydride batteries are more economical and suitable for in plug-in hybrid electric two-wheelers.
Batteries are one of the most common devices used for saving electrical energy in various applications. It is necessary to understand the battery behavior and performance during charge and discharge cycles. An accurate model of a battery with a specific application is needed for an appropriate analysis and simulation. Therefore, in the field of battery modeling, various models have been proposed. This paper presents an overview of several electrical battery models. These models are classified into six categories. The parameter details of a battery model will not be computed but a brief description of them is given. Furthermore, the applications of each model are discussed. Finally, a comparison between presented models will be made.
Arrays of manganese oxide nanowires were electrodeposited into anodized alumina membranes. These nanowire arrays were investigated in terms of their structural and electrochemical properties as cathodes for high energy and high power density Li ion batteries. The nanowire arrays were assembled with a Li counter electrode and non-aqueous electrolyte to form secondary batteries. These cells were capable of multiple charge/discharge cycles, with a cathode specific capacity of approximately 300mAh/g. Though the cathodes were fabricated without any binder or conductive additives, the electrodes could be discharged at current densities up to 0.1mA/cm2 before the onset of any significant polarization.
In this work, we put forward a novel cathode host for Li-S batteries by loading titanium nitride (TiN) nanoparticles into the pores of N-doped carbon as a proof-of-concept. The selection of TiN arises from its strong binding ability with polysulfide and its exceptionally high conductivity of 5 × 106 S/m. As for N-doped porous carbon, it provides necessary physical adsorption and extra chemical adsorption sites from the N-doping. Besides the above advantages, the most substantial merit endowed to this structure is the pore-loaded TiN design. The carbon pore size confines the TiN precursors to the nanoscale and prevents otherwise subsequent agglomeration of TiN nanoparticles. Moreover, the pore-loaded TiN design, with fully exposed adsorptive surface and highly dispersed adsorptive sites, guards against the blocking of future sulfur infiltration and Li+ diffusion. The advantages of the TiN loaded N-doped carbon are finally confirmed by electrochemical evaluations. The capacity is found up to be 1338 mAh/g at a current density of 0.2 C and 690 mAh/g at a current density of 5 C (where 1 C = 1672 mAh/g). For durability evaluations, the capacity is maintained at 700 mAh/g after 800 cycles with a mere decay of 0.04% per cycle. Lastly, the feasibility of a high mass loading with 7 mg/cm2 is demonstrated.
The main objective of this paper is to design and implement an improved intelligent state-of-health (SOH) estimator for estimating the useful life of lead-acid batteries. Laboratory studies were carried out to measure and record the distributed range of characteristic values in each SOH cycle for the battery subject to cycles of charging and discharging experiments. The measured coup de fouet voltage, internal resistance, and transient current are used as characteristics to develop an intelligent SOH evaluation algorithm. This method is based on the extension matter-element model that has been modified in this research by adding a learning mechanism for evaluation SOH of batteries. The proposed algorithm is relatively simple so that it can be easily implemented with a programmable system-on-chip (PSOC) microcontroller achieve rapid evaluation of battery SOH with precision by using a concise hardware circuit.