batterydata/paper-abstracts huggingface dataset:
State-of-charge (SOC) determination becomes an increasingly important issue in all the applications that include a battery. Former operation strategies made use of voltage limits only to protect the battery against deep discharge and overcharge. Currently, battery operation is changing to what could rather be called battery management than simply protection. For this improved battery control, the battery SOC is a key factor. Much research work has been done in recent years to improve SOC determination. Operational conditions differ for batteries in, for example, photovoltaic applications, (hybrid)-electric vehicles or telecommunications. Hence, a given method for SOC calculation will be more suitable for a certain application than for another. The authors introduce commonly used methods for SOC determination and establish a relationship between the advantages of the different methods and the most common applications. As a main illustration, the analysis of Kalman filter technique for lead-acid battery SOC determination are presented and some results for other calculation methods as well.
Much attention has been paid to thin crystalline silicon (c-Si) photovoltaic devices due to their excellent flexibility characteristics, stable efficiency, and possibility of use as highly efficient next-generation flexible photovoltaic devices (FPVs). To fabricate thin c-Si FPVs, it is important to improve their light-absorption properties while maintaining the flexible characteristics. In this study, vertically aligned microwires (MWs) on a 50 μm-thick thin c-Si substrate are designed for novel FPVs. Increasing the length of the MWs enhances the optical properties of the thin c-Si without affecting its flexibility. To maximize the efficiency of the thin c-Si FPVs with MWs, tapered MWs and a localized back-contact structure are devised. This device shows a maximum efficiency of 18.9%. In addition, the proposed thin c-Si FPV with MWs shows high stability without any change in efficiency, even with 1000 bending cycles with a bending radius of 12 mm. Thus, we successfully demonstrate battery-free flexible electronic devices integrated with our thin c-Si FPVs with MWs.
Lithium-ion battery cathodes have been fabricated by screen-printing through the development of C-LiFePO4 inks. It is shown that shear thinning polymer solutions in N-methyl-2-pyrrolidone (NMP) with Newtonian viscosity above 0.4Pas are the best binders for formulating a cathode paste with satisfactory film forming properties. The paste shows an elasticity of the order of 500Pa and, after shear yielding, shows an apparent viscosity of the order of 3Pas for shear rates corresponding to those used during screen-printing. The screen-printed cathode produced with a thickness of 26μm shows a homogeneous distribution of the active material, conductive additive and polymer binder. The total resistance and diffusion coefficient of the cathode are ∼450Ω and 2.5×10−16 cm2 s−1, respectively. The developed cathodes show an initial discharge capacity of 48.2mAhg−1 at 5C and a discharge value of 39.8mAhg−1 after 50 cycles. The capacity retention of 83% represents 23% of the theoretical value (charge and/or discharge process in twenty minutes), demonstrating the good performance of the battery. Thus, the developed C-LiFePO4 based inks allow to fabricate screen-printed cathodes suitable for printed lithium-ion batteries.
The main difficulty in the extensive commercial use of polymer electrolyte membrane fuel cells (PEMFCs) is the use of noble metals such as Pt-based electrocatalyst at the cathode, which is essential to ease the oxygen reduction reaction (ORR) in fuel cells (FCs). To eliminate the high loading of Pt-based electrocatalysts to minimize the cost, extensive study has been carried out over the previous decades on the non-noble metal catalysts. Development in enhancing the ORR performance of FCs is mainly due to the doped carbon materials, Fe and Co-based electrocatalysts, these materials could be considered as probable substitutes for Pt-based catalysts. But the stability of these non-noble metal electrocatalysts is low and the durability of these metals remains unclear. The three basic reasons of instability are: (i) oxidative occurrence by H2O2, (ii) leakage of the metal site and (iii) protonation by probable anion adsorption of the active site. Whereas leakage of the metal site has been almost solved, more work is required to understand and avoid losses from oxidative attack and protonation. The ORR performance such as stability tests are usually run at low current densities and the lifetime is much shorter than desired need. Therefore, improvement in the ORR activity and stability are the key issues of the non-noble metal electrocatalyst. Based on the consequences obtained in this area, numerous future research directions are projected and discussed in this paper. Hence, this review is focused on improvement of stability and durability of the non-noble metal electrocatalyst.
New functionalized ionic liquids (ILs), comprised of multi-methoxyethyl substituted quaternary ammonium cations (i.e. [N(CH2CH2OCH3)4−n (R) n ]+; n =1, R=CH3OCH2CH2; n =1, R=CH3, CH2CH3; n =2, R=CH3CH2), and two representative perfluorinated sulfonimide anions (i.e. bis(fluorosulfonyl)imide (FSI−) and bis(trifluoromethanesulfonyl)imide (TFSI−)), were prepared. Their fundamental properties, including phase transition, thermal stability, viscosity, density, specific conductivity and electrochemical window, were extensively characterized. These multi-ether functionalized ionic liquids exhibit good capability of dissolving lithium salts. Their binary electrolytes containing high concentration of the corresponding lithium salt ([Li+] >1.6molkg−1) show Li+ ion transference number ( t L i + ) as high as 0.6–0.7. Their electrochemical stability allows Li deposition/stripping realized at room temperature. The desired properties of these multi-ether functionalized ionic liquids make them potential electrolytes for Li (or Li-ion) batteries.
Fuel traffic to the Syowa Base of the South Pole is increasing from Japan, with growing research and observation occurring every year. Limits to fuel traffic and the spread of green energy utilization are topics of interest for Syowa Base; this research considers the construction of a Syowa Base small-scale energy network (Syowa Base Micro-Grid: SBMG) for the purposes of reducing fuel consumption and increasing green energy utilization. The number of engine generators, the operation plan for the battery’s charge and discharge, and the introduction of an exhaust heat pump provided a means by which the load factor of the engine generator could be maintained high value from the fluctuations of green energy. This might be accomplished by modifying the main power supply of Syowa Base into a distributed power supply system rather than a conventional central power supply system. The relationship between the amount of green energy (photovoltaics and wind power generation) connected to the proposed power supply distribution and the amount of fuel consumed by the engine generators and backup boiler was clarified. Moreover, the outside temperatures, insulation levels, and wind velocity at the Syowa Base change seasonally, resulting in large changes in the SBMG operation method. Therefore, differences in the operation methods between the proposed power supply distribution system and the conventional central power supply were assessed during the summer (January), winter (July), and mid-season (October), and the resulting differences in fuel consumption were clarified.
Tin-based compounds have incurred tremendous attention due to their higher specific capacities than their analogues for lithium storage. Unfortunately, the undesirable electrical conductivities and huge volume variations during cycling processes coupled with Li+ intercalation and de-intercalation will lead to severe capacity fading and poor cycling stability. To address these problems, nitrogen-doped carbon-coated SnO2/SnS (SnO2/SnS@N-C) composite was in situ synthesized by virtue of a simple solvothermal reaction and subsequent post-treatment. Herein, the heterostructures between SnO2 and SnS were designed to accelerate charge transfer by using the effect of internal electric field and improve the dispersion among particles. While coating the nitrogen-doped carbon on heterostructures aimed to improve electrical conductivities and relieve huge volume alterations during the processes of Li+ insertion and de-insertion. To our satisfactory, the as-prepared SnO2/SnS@N-C composite as anodes for lithium-ion batteries can display a high specific capacity (1050 mAh g−1 at 100 mA g−1), enhanced rate capability, and long cycle life (550 mAh g−1 after 100 cycles), which outperforms both SnO2@N-C and SnS@N-C. The promotion of electrochemical performance demonstrates that Tin-based anode materials with such optimized structures have broad prospects in the applications of energy storage field.
Designing and fabricating electrodes with excellent mechanical flexibility and superior electrochemical performance for high-performance lithium ion battery (LIBs) is challenging. Herein, ultralong peapod-like nanowires (NWs) composed of short vanadium sesquioxide nanorods (V2O3 NRs) encapsulated with carbon are produced as high-performance anode materials. The freestanding and flexible film has a high capacity of 210 mAh g−1 at a current density of 0.1 C, and exhibits appreciable rate capability with 68% capacitance retention when the current density is increased from 0.1 to 1 C, and excellent long-term cycling stability without apparent capacity fading after 125 cycles, which is better then that of the active carbon mixed V2O3 NRs and bare V2O3 NRs. The outstanding electrochemical performance is attributed to proper accommodation of the volume expansion of the vanadium oxide in the carbon in the lithiation/delithiation process as well as the outer conductive three-dimensional (3D) carbon network. The formation mechanism of the peapod-like structure is investigated by thermogravimetric analysis connected to a mass spectrometer (MS). The ultralong peapod-like nanostructure overcomes the physical and chemical drawbacks of vanadium oxide and has large potential applicability for flexible energy-storage devices.
Although silicon technology has been the main driving force for miniaturizing device dimensions to improve cost and performance, the current application of Si to soft electronics (flexible and stretchable electronics) is limited due to material rigidity. As a result, various prospective materials have been proposed to overcome the rigidity of conventional Si technology. In particular, nano-carbon materials such as carbon nanotubes (CNTs) and graphene are promising due to outstanding elastic properties as well as an excellent combination of electronic, optoelectronic, and thermal properties compared to conventional rigid silicon. The uniqueness of these nano-carbon materials has opened new possibilities for soft electronics, which is another technological trend in the market. This review covers the recent progress of soft electronics research based on CNTs and graphene. We discuss the strategies for soft electronics with nano-carbon materials and their preparation methods (growth and transfer techniques) to devices as well as the electrical characteristics of transparent conducting films (transparency and sheet resistance) and device performances in field effect transistor (FET) (structure, carrier type, on/off ratio, and mobility). In addition to discussing state of the art performance metrics, we also attempt to clarify trade-off issues and methods to control the trade-off on/off versus mobility). We further demonstrate accomplishments of the CNT network in flexible integrated circuits on plastic substrates that have attractive characteristics. A future research direction is also proposed to overcome current technological obstacles necessary to realize commercially feasible soft electronics.
Planar ultracapacitors of miniature interdigital electrode are prepared, using the standard technologies of photolithography and reactive sputtering. The ultracapacitor is denoted by its deposition sequence, for example, hRuO2NRGT indicates pseudocapacitive hydrous RuO2 (hRuO2) and RuO2 nanorods (NR) are grown on an interdigital stack layer of gold (G) and titania (T). The connection between structure and performance is studied through contrasting the hRuO2NRGT capacitor with other capacitors built on a less conducting stack layer or without hydrous RuO2 filling the gaps between the nanorods. The stack layer can be a major source of cell resistance. For instance, a buffer layer of titania could be utilized between the capacitive RuO2 and the Au current collector to overcome the delamination problem. But the less conductive titania also makes its cyclic voltammograms (CV) elliptical and tilted, and causes a pronounced IR drop during the cell discharging. In contrast, CV of the hRuO2NRGT capacitor on a conductive stack layer takes the shape of horizontal rectangle, and its discharge curve shows no sign of IR drop. Filling hydrous RuO2 into the gap reduces the cell resistance between nanorods, improves the discharge performance as well. The power output of hRuO2NRGT, with the two resistances minimized, is 30.6μW at 75μA and 1.23μW at 5μA.
This paper reports on the development of key components, specifications, configuration and operating characteristics of a hydrogen-fueled portable power source with polymer electrolyte fuel cell (PEFC). A 1kW class fuel cell module operating on an exclusive method of internal humidification was developed for the power source. A dc–ac inverter, in which a general-purpose integrated power module (IPM) was used as a switching device for microprocessor-based power conversion control, was developed to save the cost of generating dc power output from the cell module. The power source supplies full power within 2min from start-up, and is capable of generating rated 1kW power for about 3h and even longer if the cylinders are replaced. This power source has been confirmed to offer a high power generation efficiency of 30% or higher in overall output range, yielding good-quality power with little noise.
A new nanocomposite formulation of the iron-based anode for alkaline secondary batteries is proposed. For the first time, FeS nanoparticles anchored on reduced graphene oxide (RGO) nanosheets are synthesized via a facile, environmentally friendly direct-precipitation approach. In this nanocomposite, FeS nanoparticles are anchored uniformly and tightly on the surface of RGO nanosheets. As an alkaline battery anode, the FeS@RGO electrode delivers a superior high-rate charge/discharge capability and outstanding cycling stability, even at a condition without any conductive additives and a high electrode loading of ∼40 mg cm−2. At high charge/discharge rates of 5C, 10C and 20C (6000 mA g−1), the FeS@RGO electrode presents a specific capacity of ∼288, 258 and 220 mAh g−1, respectively. Moreover, the FeS@RGO electrode exhibits an admirable long cycling stability with a superior capacity retention of 87.6% for 300 cycles at a charge/discharge rate of 2C. The excellent electrochemical properties of the FeS@RGO electrode can be stemmed from the high specific surface area, peculiar electric conductivity and robust sheet-anchored structure of the FeS@RGO nanocomposite. By virtue of its superior fast charge/discharge properties, the FeS@RGO nanocomposite is suitable as an advanced anode material for high-performance alkaline secondary batteries.
The solid electrolyte interphase (SEI) of graphite electrodes has been extensively studied using surface sensitive techniques such as photoelectron spectroscopy (PES) and soft X-ray spectroscopy. By combining measurements of reference compounds with graphite electrodes cycled in different electrolytes and under different conditions, knowledge of the solid electrolyte interphase (SEI) chemistry can be obtained. In this article, conclusive results concerning the chemical composition of the inorganic part of the SEI is described. The results show that Li2O often reported to be present in the SEI could be an artifact from abusive Ar+ sputtering. The presence of Li2CO3 is a matter of debate; the compound is not observed in anodes extracted from hermetically sealed cells that are never exposed to air. The results show that cell-design and sample handling are crucial to the observed chemical composition of the SEI.
We have developed binder-free electrode materials composed of CoO quantum dots on three-dimensional (3D) graphene hydrogels. The CoO quantum dots with size of only 3∼6nm are uniformly decorated onto the surface of graphene, then as building blocks assembled to 3D structures during a solvothermal process. The designed electrode configuration takes advantage of ultra-small particle sizes, large surface area, 3D microstructures, and good electronic conductivities. These merits lead to the 3D CoO quantum dots/graphene hybrid hydrogels exhibiting specific capacitances of 889.7∼822Fg−1 at current densities of 2 to 50Ag−1, capacitance retention as high as 92.4%. The hybrid energy storage devices by using our hybrid hydrogels as positive electrodes and pure graphene hydrogels as negative electrodes can deliver an energy density of 28.7 and 23.0 Wh kg−1 at a power density of 1600 and 12000Wkg−1, and exhibit remarkable long-term stability with almost no capacitance loss at all even up to 5000 cycles, indicating that our designed 3D CoO quantum dots/graphene hybrid hydrogels would be one of the promising active materials for energy storage applications.
The LiNi0.5−x Cu x Mn1.5−y Al y O4 (x = 0, 0.05, y = 0, 0.05) powders are synthesized by liquid co-precipitation and wet-milling. The doping effect on LiNi0.5Mn1.5O4 by Al3+, Cu2+, and Al3+/Cu2+ co-doping are investigated and compared in relation to physical and electrochemical characterization, namely, through X-ray diffraction, scanning electron microscopy, electronic conductivity, cyclic voltammetry and cycle tests. Results suggest that both Al3+ and Cu2+ doping effectively improve electrochemical performance of LiNi0.5Mn1.5O4, although the effect is different between the two cations. All doped samples exceed 95% capacity retention after 100 cycles at room temperature compared to 92% retention for the undoped sample. Moreover, co-doped LiNi0.45Cu0.05Mn1.45Al0.05O4 exhibits the best cyclic performance with slight superiority.
Chemical reactions occurring during the processing of positive and negative active material of lead-acid batteries have a significant impact on the performance and life of the product. Understanding and control of these chemical and electrochemical processes will result in batteries which consistently meet vehicle requirements.
Three dimensional (3D) porous self-assembled MoO2/graphene microspheres are successfully synthesized via microwave-assisted hydrothermal process in a short reaction time followed by thermal annealing. Such rationally designed multifunctional hybrid nanostructure is constructed from interconnected MoO2 nanoparticles (3–5 nm), which is self-assembled into ordered nanoporous microspheres via strong electrostatic attraction between graphene sheets and MoO2 nanoparticles. The MoO2/graphene hybrid structure delivers a high reversible capacity with significantly enhanced cycling stability (∼1300 mAh g−1 after 80 cycles at C/10 rate) and excellent rate capability (913 and 390 mAh g−1 at 2C and 5C rates, respectively), when used as an anode material. The microspheres are interconnected and well encapsulated by the flexible graphene sheets, which not only accommodates large volume change but also increases the electrical conductivity of the hybrid structure. Moreover, nanoporous voids present in the 3D framework facilitate effective electrolyte penetration and make a direct contact with the active MoO2 nanoparticles, thereby greatly enhancing lithium ion transport. The strategic combination of self-assembly, nanoporous voids, 3D network and intriguing properties of graphene sheets provides excellent electrochemical performance as anode materials for Lithium ion battery applications.
The electrochemical behavior of titanium dioxide (TiO2) in aqueous lithium hydroxide (LiOH) electrolyte has been investigated. Cyclic voltammetry shows that electroreduction results in the formation of a number of products. X-ray diffraction of the electroreduced TiO2 shows that LixTiO2, Ti2O3, Ti2O and TiO are formed. The formation of LixTiO2 is confirmed through X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) studies of the electroreduced TiO2. The formation of LixTiO2 is electro reversible. In this respect, the electrochemical behavior of TiO2 in concentrated aqueous lithium hydroxide electrolyte is similar to that for lithium perchlorate (LiClO4) non-aqueous media.
The use of microfibrous nickel substrates is advantageous for increasing the surface area available for the deposition of active material and reducing the substrate weight and consequently, yields a higher specific capacity for nickel hydroxide electrodes. Porous, microfiber-based nickel substrates were produced by sintering a composite preform. The preforms, consisting of nickel fibers with diameters as small as 2μm and cellulose fibers, were formed using a papermaking process. The fabricated nickel electrodes that included a supporting nickel mesh in the substrate tested in a 26% KOH half-cell delivered a specific capacity of more than 250mAh/g of the electrode weight (i.e. fibrous substrate, nickel mesh, and active material) at a 1.0C discharge rate. An Auburn electrode without a nickel mesh tested in the same half-cell attained a higher specific capacity of 268mAh/g at a 1.37C discharge rate. The substrates used in these electrodes had porosities of 95–97%, and greatly improved the specific capacity of the nickel electrode. With the use of the microfibrous electrode, improved specific energies of nickel-based cell and battery designs are possible. When assembled in a nickel–hydrogen (Ni–H2) boilerplate cell, the specific capacity of nearly 230mAh/g was observed for the nickel electrode at a 0.5C rate during the 127th cycle test. The results of high specific capacity and quick rise in utilization of microfibrous nickel hydroxide electrodes make these electrodes good candidates for significantly improving the energy density and performance of nickel–hydrogen cells.
This paper discusses and analyses the productivity of solar home systems in isolated areas in French Guiana, a region characterized by specific human and environmental conditions. Its aim is a better understanding of the attitudes, expectations, and relationship of the users towards the solar home system. The data collected made it possible to make suggestions for adapting the photovoltaic systems to their environment by taking into account social, cultural, and geoclimatic specificities. Analysis of on-site productivity provides valuable information on energy profiles and types of use. Field surveys made it possible to associate users’ perception of the energy production equipment and their degree of satisfaction with operating efficiency and on-site maintenance. This aspect is essential for analyzing the actual rate of use of the energy that is theoretically available. Parallel to these surveys, the results of the study carried out on the performance of the solar home systems made it possible to learn the quantitative aspects of the energy produced and consumed as well as the qualitative aspects of the parameters that condition the performance of the photovoltaic systems. After keyboarding, the subjective, qualitative as well as the quantitative variables were processed using a statistical analysis program in order to determine the correlations between them and to prepare the final conclusions.