bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preliminary Results on a 5W Portable Butane MT-SOFC Stack As a Battery Charger
Authors: Jung Han Kyu , Hong Jong-Eun , Dhir Aman , Majewski Artur Jacek , Hari Bostjan , Steinberger-Wilckens Robert , Chung Yong Sik , Sung Jae Gi , Chung Jong Shik , Sammes Nigel Mark 
Published: February 2020

A microtubular design for a solid oxide fuel cell (MT-SOFC) is studied for use in stacks for high strength and portability. Adapting readily available butane as the fuel source and intermediate temperature operation, MT-SOFC can replace batteries for various portable applications. This work studies the fabrication and preliminary performance results of a 5W MT-SOFC stack using butane as the fuel. The tubes were produced using a standard die extruder into a Ni-ceria-10mol% scandia stabilized zirconia (ScSZ) anode support. A ScSZ electrolyte and a La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) cathode were added on top of the tube, respectively, via a dip-coating method. The outer and inner diameters of the unit cell were 3mm and 2mm, respectively. The fabrication process was optimized and the electrochemical properties of a unit cell operated at intermediate (600~700oC) temperature are described. Unit cells were then stacked for an output of 5 watts.
Fig. 1. (a) Pre-sintered anode support MT-SOFC; (b) Fabricated anode support MT-SOFCs; (b) Schematic of 5W MT-SOFC stack.
Acknowledgement
This work was sponsored by KETEP No. 4.0010459.01.

Figure 1
Characterization of Terbium and Samarium Co-Doped Ceria Films as SOFC Electrolyte Prepared by Using Ultrasonic Spray Pyrolysis Method
Authors: Vestli Mihkel , Nurk Gunnar 
Published: February 2020

Because of the high ionic conductivity at intermediate temperatures (500–700 °C), doped ceria oxides are of special interest as the promising electrolyte materials for the intermediate temperature solid oxide fuel cells (IT-SOFC). However, main drawback of the ceria based solid electrolytes is the partial electronic conductivity at reducing conditions resulting in an internal partial short-circuiting of the cell and decreased total efficiency for SOFC. Tb, considered an electron trap, was found to suppress the partial electronic conductivity for microcrystalline ceria electrolyte. The aim of this work is to study the influence of Tb and Sm dopant concentration ratio on the microstructural and electrical properties of Ce0.9Sm0.1-xTbxO2-δ films.
Tb and Sm cations binary co-doped ceria films were deposited using the ultrasonic atomizing spray pyrolysis method. The crack-free homogenous films with different dopant concentration were deposited and thereafter annealed at fixed temperatures 900, 1200 and 1300 °C, respectively. It was demonstrated that several microstructural parameters of oxide films are controlled by the sintering temperature. The Ce0.9Sm0.1-xTbxO2-δ films formed were analyzed using X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, atomic force microscopy and four probe dc technique at different pO2 and T values.
Based on the SEM analysis the average thickness of Ce0.9Sm0.1-xTbxO2-δ films were 700 nm. The XRD patterns for the Ce0.9Sm0.1-xTbxO2-δ films annealed at 1200 °C indicated the high degree of crystallinity. Tb dopant ions influence the microstructural properties like median diameter of grain, microstrain, lattice parameter and electrical properties like activation energies of ionic and electronic conductivity of the Ce0.9Sm0.1-xTbxO2-δ film. Significantly higher microstrain value for smallest Tb dopant concentration and strong dependence of electrical properties on that was observed. The activation energy of ionic conductivity was lowered in that case, while the activation energy of electronic conductivity was increased. The lower bound of electrolytic domain for Ce0.9Sm0.09Tb0.01O2-δ film was lowered by one order of magnitude toward lower oxygen partial pressures. Further increase of Tb amount increased the activation energy of ionic conductivity, shifting the lower bound of electrolytic domain toward higher oxygen partial pressures.
Systematic Parameter Study on the Influence of Humidification and Current Density on SOEC Degradation
Authors: Hoerlein Michael P. , Schiller Guenter , Tietz Frank , Friedrich K. Andreas 
Published: February 2020

A special measurement setup with the ability to measure four cells simultaneously in reversible SOEC/SOFC mode was implemented. As preliminary experiment extensive characterization of anode supported Ni-YSZ|YSZ|CGO|LSCF cells provided by Forschungszentrum Jülich was conducted including polarization curves and impedance measurements in the range from 750 °C to 850 °C and fuel gas humidifications from 40 mol% H2O to 80 mol% H2O in SOFC and SOEC mode.
Core of this work is the systematic investigation of the influence of the operating parameters temperature, fuel gas humidification and current density on SOEC long-term degradation and its underlying individual processes. In order to obtain this information a series of five 1000 h experiments with an operating temperature between 750 °C to 850 °C and fuel gas humidification between 40 mol% H2O to 80 mol% H2O was devised. During each measurement over 1000 h four cells are measured simultaneously under identical conditions with the exception of current density where each cell runs galvanostatically with a fixed value between 0 A/cm2 and 1.5 A/cm2. The progress of degradation was monitored in-situ approximately every 150 h by impedance spectroscopy. It was possible to isolate fuel electrode processes R1+2, an oxygen electrode process R3, a mass transport limitation on the fuel electrode R4 and the electrolyte resistance R0. It could be shown that the processes R0 and R1+2 show a strong correlation between current density and degradation; however the processes R3 and R4 exhibit degradation behavior completely independent of the applied current. Furthermore it could be shown that the oxygen electrode process R3 demonstrates rapid degradation during the first approximately 500 h dominating the overall cell degradation, however slowing down to be negligible after 1000 h.
Post-mortem investigations are being conducted in order to localize and identify the rate limiting processes R0 to R4. In this way we will be able to explain the observed degradation for each process and also validate the observed dependencies ex-situ. Additionally, the remaining long-term experiments are being conducted in order to complete this study and clarify the correlation between degradation processes and fuel gas humidity as well as operating temperature.
Ceres Power Steel Cell Technology: Rapid Progress Towards a Truly Commercially Viable SOFC
Authors: Leah Robert Timothy , Bone Adam , Lankin Mike , Selcuk Ahmet , Rahman Mahfujur , Clare Andrew , Rees Lee , Phillip Stephen , Mukerjee Subhasish , Selby Mark 
Published: February 2020

Ceres Power is continuing to make excellent progress in the development of its low-temperature metal supported SOFC design (the ‘Steel Cell’) based predominantly around the use of ceria. This unique design architecture allows for a robust, low cost, subsidy free fuel cell product, whilst retaining the advantages of fuel flexibility, high efficiency and low degradation.
Over the last year, extensive development and verification of the technology has been undertaken on the latest generation of Steel Cell technology, which offers further enhancements in technology readiness level and manufacturability. Over the same period, third parties have deepened their testing and development engagements with Ceres Power for a broadening range of market applications at cell, stack, fuel cell module and product levels. This paper provides an update on Ceres’ development, verification approach and latest results.
Effects of Doping on O Ion Migration in Pr2NiO4-Based Oxides
Authors: Aspera Susan Meñez , Sakaue Mamoru , Alaydrus Musa , Linh Nguyen Hoang , Kasai Hideaki 
Published: February 2020

Recent studies related to SOFC technology involve materials design on the electrodes and electrolyte layes in search of candidate materials with high O ion conductivity even at lower operating temperatures. This involves understanding the detailed mechanisms of O ion diffusivity at materials which are known to be good O ion conductors at low temperatures. From the many candidate materials, a group of perovskite materials in the K2NiF4 structure has been eyed as promising materials for these purpose, specifically Pr2NiO4-based materials. Interest in the study of Pr2NiO4 and Pr2NiO4-based materials rooted from its potential application as a mixed ionic and electronic conductor (MIEC) as a cathode material for SOFC.
In this study, first principles calculation based on density functional theory (DFT) was used to analyze the structural and electronic properties of Pr2NiO4 and doped Pr2NiO4 systems (Pr2-yRyNi1-x-y-zExTzO4 (R=La, and E=Cu and T=Ga)). With the aim of determining possible Pr2NiO4-based candidate materials for the electrolyte layer, the effects of doping on the migration of O-2 on an assumed promising system was analyzed.
Two types of cation dopant sites were assumed in this study: (1) a large cation dopant substituting Pr, and (2) a smaller cation dopant substituting Ni. For the first case, the effect of La dopants, with different concentrations, on the change in the structural and electronic properties of the host bulk structure was analyzed. It was observed that La dopants have a dominant effects on the change in the lattice parameter along the the c direction due to the difference in ionic radius. This is assumed to be a factor affecting the O ion conductivity within the material. For the second case, co-doping of Cu and Ga (Pr2Ni0.5Cu0.25Ga0.25O4), and doping of Ga (Pr2Ni0.5Ga0.5O4) with different structures were analyzed. For the co-doped system, it was observed that due to nearly similar atomic radii of Cu and Ga, no cation-O atoms elongation were observed. Cu dopants are considered to increase the electronic conductivity of the system. On the other hand, Ga doping shortens the Ga-Oap distance while elongating the Ni-Oap distance, which affects O ion migration through interstisialcy. Furthermore, electronic property analysis also shows that there is a minimal state for the Ga orbitals along the Fermi level as compared with the host Ni atom. And that higher oxidation state of Ga than Ni will tend to cause increased concentration of interstitial O atoms. These results show favorable characteristics for an electrolyte material.
In Situ TEM Temperature Study of Solid State Reaction of Lanthanum Oxide and Chromia
Authors: Karlsson Lisa S , Olsson Claes-Olof A , Lundberg Mats W , Berger Robert , Westlinder Jörgen 
Published: February 2020

Rare earth elements like La and Ce are known to improve the corrosion resistance of coated ferritic steels [1, 2]. The solid state reaction between La-rich oxide and Cr2O3 has been studied by x-ray diffraction (XRD) and in situ heating TEM with electron diffraction. The La-rich oxide powder was found to be porous and polycrystalline and would start by healing the pores and forming a transition phase of orthorhombic CrLaO3 [3] before migration of La is found at the interfaces (Figure 1). After full reaction pure La2O3 has been observed by HRTEM in a region initially starting as porous La-rich oxide (Figure 2).
1. S. Canovic, et al., Oxidation of Co- and Ce-nanocoated FeCr steels: A microstructural investigation. Surface & Coatings Technology, 2012.
2. M.W. Lundberg, et al., Precoated AISI441 for SOFC interconnectors studied by TEM methods. ECS Transactions, 2013. 57(1): p. 2321-2329.
3. C.P. Khattak and D.E. Cox, Structural Studies of the (La,Sr)CrO3 System. Materials Research Bulletine, 1977. 12: p. 463-472.

Figure 1
Study on Cycle Life of Lithium-Ion Batteries Using in Situ
7li Solid-State Nuclear Magnetic Resonanc
Authors: Arai Juichi , Nakahigashi Rie , Sugiyama Teruyasu 
Published: February 2020

The life of the lithium-ion batteries (LIBs) used as power sources for electrically powered vehicles, such as e-scooters, e-bikes, and electrically assisted wheel chairs, is critical for the stable operation of these products throughout their lifetime. Understanding the battery life may help in improving the performance of the vehicles powered by LIBs. However, examining the degradation mechanism without disassembling the cell is not easy. Thus, the cell life of the same cell cannot be tracked. Hence, in situ measurements are required.
We have developed an in situ
7Li solid-state nuclear magnetic resonance (NMR) measurement and studied the reaction inside the LIBs without decomposition [1,2]. We applied this technique to the analysis of the battery cycle life. The Li intercalation in carbon (graphite intercalation compound, GIC) was monitored every 100 cycles during cycle tests that were performed at 10 and 25 °C with 0.5 and 1 C discharge rates, respectively. The cell was composed of a LiCoO2 positive electrode, a carbon negative electrode, and an organic electrolyte (ethylene carbonate (EC)/ethyl methyl carbonate (EMC) with 1 M LiPF6). Fig. 1 shows the spectra measured at 100% state of charge (SOC), a fully charged mode at 0.2 C constant-current and constant-voltage (CCCV), every 100 cycles at 25 °C.

K. Gotoh, M. Izuka, J. Arai, Y. Okada, T. Sugiyama, K. Takeda, H. Ishida, Carbon, 79, 380 (2014).

J. Arai, Y. Okada, T. Sugiyama, K. Gotoh, M. Izuka, K. Takeda, ECS Trans. 62(1), 159 (2014).

Figure. 1. Spectra measured at 100% state of charge (SOC) (a) before the cycle test, (b) after 100 cycles, (c) after 200 cycles, and (d) after 300 cycles.

Figure 1
Scalable Synthesis of Composite As Cathode in Li-S Batteries with Improved Performance
Authors: Niu Junjie 
Published: February 2020

On the demand of large-scale energy storage, the secondary lithium-ion batteries (LIBs) are attracting more attentions on portable devices and electric vehicles. Numerous efforts are being taken into finding new electrode materials which have folds higher capacity with respect to the traditional materials over the last decade. In particular, scientists have explored silicon shows a 7-10 times higher capacity of >2000 mAh/g than the commercial graphite. However, on the cathode side, substantial capacity improvement in comparison of silicon anode is lacking, which largely restrict the commercialization of high energy density batteries. Sulfur has been identified as one of most promising cathode materials for its high theoretical capacity (1675 mAh/g, 8-10x times higher than LiCoO2) and the theoretical specific energy (~2600 Wh/kg, 5x times higher than LiCoO2/graphite) of Li-S battery. Nevertheless, researchers remain stagnant in pushing this high power-density battery into industrial applications. The major barrier is from the rapid capacity decay, which is due to the low electrical conductivity, volume expansion and the shuttling effect. Averting chemomechanical degradation thus poses as one of the primary challenges in exploiting sulfur cathodes in the development of next-generation batteries.
Here we present a scalable synthesis of lithium-sulfur composite cathode with improved performance. An open network of conductive carbon black nanoparticles (Cnet) is infused with sulfur (Snet) to form sponge-like interpenetrating, doubly percolating random networks (Cnet + Snet). A >750 mAh/g discharge specific capacity of this sulfur nanosponge cathode was received after 100 cycles under a rate of 0.2 C. A >500 mAh/g discharge capacity was attained after 300 cycles, making this cathode material attractive for powering portable electronic devices.
Analysis of All-Solid Li-Ion Batteries By Photoelectron Spectroscopy: Experimental Procedures, Interpretation and Results
Authors: Fingerle Mathias , Schwöbel André , Precht Ruben , Jaegermann Wolfram , Hausbrand René 
Published: February 2020

Electrochemical devices such as lithium-ion secondary batteries consist of complex layer systems with interfaces and interphases that play a crucial role in cell performance and degradation. The understanding of the energy level alignment and double layer formation especially at electrode-electrolyte interfaces is therefore mandatory. Photoelectron Spectroscopy (PES) is a reliant tool and widely accepted method in surface science to probe the electronic structure of thin, electronically conducting layer systems on a nanometer scale, e.g. of semiconductor devices. For such systems, an aligned Fermi level (i.e. electrochemical potential of electrons) can usually be presumed resulting in well-defined experimental conditions for PES. For ionic systems involving (solid) electrolytes, the experimental conditions are less clear due to the lack of sufficient electronic conductivity. Nevertheless, also in such cases PES proofs to be a useful tool, i.e. for analysis of solid electrolytes or characterization of full cells and interfaces [1].
In this contribution, we focus on the different electrolyte- and ionic-interface related effects, such as charging and Fermi level misalignment, and discuss experimental strategies and interpretation of PES measurements. By example of a LiCoO2|LiPON|Li thin film battery, we demonstrate how interface experiments and analysis of the top electrode of a layer stack can be performed and interpreted. Key factors taken into consideration are the electrochemical equilibrium of the lithium ions at the interfaces as well as the ability of the electrolyte to sustain an electric (ionic) current, given corresponding (de)intercalation reactions are triggered. Next to information on electron energy level alignment and double layer formation, information on ion energy levels, ionic and electronic contribution to cell voltage, formation of reaction layers as well as electronic structure of intercalation electrodes can be obtained from suitable experiments (see e.g.[1-3]).
1. Hausbrand, R., D. Becker, and W. Jaegermann, A surface science approach to cathode/electrolyte interfaces in Li-ion batteries: Contact properties, charge transfer and reactions. Progress in Solid State Chemistry, 2014. 42(4): p. 175-183.
2. Tonti, D., C. Pettenkofer, and W. Jaegermann, In-Situ Photoelectron Spectroscopy Study of a TiS2 Thin Film Cathode in an Operating Na Intercalation Electrochemical Cell. Ionics, 2000. 6(3-4): p. 196-202.
3. Schwöbel, A., R. Hausbrand, and W. Jaegermann, Interface reactions between LiPON and lithium studied by in-situ X-ray photoemission. Solid State Ionics, in press.
Nickel Sulfide/Carbon Nanotube Nanocomposites As High Performance Cathode Materials for Asymmetric Supercapacitors
Authors: Lin Jeng-Yu , Chou Shu-Wei 
Published: February 2020

Recently, supercapacitors have attracted extensive attention due to their unique properties of long cycling life, low maintenance cost, and high power density. Furthermore, supercapacitors show great potential applications for energy-storage systems in portable electronic devices and hybrid electric vehicles. Typically, supercapacitors have two mechanisms of the charge storage/delivery, namely the electric double-layer capacitors (EDLC) and psuedocapacitors. The pseudocapacitor usually shows a higher value of specific capacitance (Cm) than EDLC due to the presence of the Faradaic process. However, both EDLC and the pseudocapacitor show lower specific energy densities than batteries. Therefore, the development of the supercapacitors with high power and energy densities is still a challenge.
In this study, the Ni3S2/carbon nanotube composites were successfully developed by means of the glucose-assisted hydrothermal method. The composite electrode shows a high specific capacitance of 800 F/g and great cycling stability at a current density of 3.2 A/g. Furthermore, an asymmetric supercapacitor device was fabricated by using the composite of Ni3S2 and MWCNTs as the cathode and activated carbon as the anode. The fabricated device can be operated reversibly between 0 and 1.6 V, and obtain a high specific capacitance of 55.8 F/g at 1 A/g. It also delivers a maximum energy density of 19.8 Wh/kg with a power density of 798 W/kg. As a result, the asymmetric supercapacitor device based on the Ni3S2/MWCNTs cathode can be considered as a promising energy storage device.
Low Voltage Anodes for Lithium-Ion Batteries
Authors: Clark Steve , Armstrong Anthony Robert , Bruce Peter G 
Published: February 2020

Graphite has proved a highly successful anode for lithium ion batteries; however it is not without its limitations. There is intensive research to perfect silicon based anodes but important challenges still remain in the quest for high cycling efficiency and high cycle numbers. As a result, there remains much need for investigation of alternative anodes for lithium-ion batteries. Recently we investigated anodes based on LiVO2
1,2. Intercalation into this compound, which is isostructural with LiCoO2, occurs in a two phase process with the formation of hexagonal Li close packed Li2VO2.1 We have now extended these studies to related compounds, and solid solutions, and have identified anodes with a capacity of over 205 mAh/g at C rate, Fig. 1. The density of these materials is 3.34 g/cm3 resulting in a volumetric capacity of 718 mAh/cm3 at 1C. Volumetric capacity is important for applications such as electric vehicle. Detailed results of these investigations will be presented in the meeting.
References:
1) A.R. Armstrong, C. Lyness, P.M. Panchmatia, M.S. Islam, P.G. Bruce, Nat. Mater. 10 (2011) 223-228.
2) F.d.r. Pourpoint, X. Hua, D.S. Middlemiss, P Adamson, D Wang, P.G Bruce, C.P. Grey, Chem. Mater. 2012, 24, 2880−2893.

Figure 1