bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sulfur Poisoning of LSCF Cathode in Single Step Co-fired SOFC
Authors: Mori Naoya , Sato Yosuke , Iha Michiaki , Takada Takahiro , Konoike Takehiro , Kishimoto Haruo , Yamaji Katsuhiko , Yokokawa Harumi 
Published: February 2020

Murata Manufacturing Co., Ltd. has been developing planar-type solid oxide fuel cells (SOFCs) based on new design concept. The cell is fabricated by a single-step co-firing process and consists of an electrolyte, electrodes, current collectors, gas-separators with manifolds, and gas-flow channels. The membrane electrode assembly (MEA) is sandwiched between ceramic gas-separators with via-hole electrodes providing electrical paths between cells. Removing metal interconnects around cathode in the cell enables reducing Cr vapor from metal and achieving high durability. A long-term operation has been carried out at 750°C over 8000h under galvanostatic condition. Single cell voltage degradation rate was less than 0.20%/kh after 2000h operation, and Cr poisoning in the LSCF cathode after long term operation over 8000h was not observed. From these results, the cell structure is effective to reduce Cr vapor in the cathode. But Sulfur distribution in the cathode was observed by analyzing in detail. Larger amount of Sulfur to form SrSO4 was distributed at the air channel on the upstream than that on the downstream. And furthermore, Co segregation was observed in LSCF near the GDC barrier layer at the air channel on the upstream. To study sulfur poisoning mechanism, SO2 poisoning test was carried out with various temperature and current density. Distribution of Sulfur and Co depended on operating temperature and current density.
Role of Strain Ans Sr-Doping for the Anisotropic Oxygen Diffusion in LaMnO3
Authors: Salawu Omotayo akande , Gan Liyong , Schwingenschlogl Udo 
Published: February 2020

A high ionic conductivity is desireable property for cathode materials for
solid oxide fuel cells. LaMnO3 is a well studied candidate for this applica-
tion. Hence, it is important to understand the oxygen transport mecha-
nism. We find increase in oxygen vacancy formation energy and diffusion
under compressive and tensile strain as well as under Sr-doping using the
density functional theory and nudged-elastic band calculations. The oxy-
gen vacancy sites and diffusion paths are studied. We investigate the effect
of Sr-doping on the anisotropy of the diffusion. Modified strengths of
the Mn and O bonding as well as volume change are identified as fac-
tors that affect the formation/diffusion of vacancies. Furhermore, tensile
strain facilitates enhanced oxygen vacancy diffusion along the [011]/[0 ̄11] direction. The weakening of the Mn- O bonds as well as the distortion of
the MnO6 octahedra hinder diffusion along the [110]/[1 ̄ 10}direction.
Effect of Nature of the Ceramic Component of the Composite Electrodes Based on La1.7Ca(Sr)0.3NiO4+δ on Their Electrochemical Performance
Authors: Pikalova E. , Bogdanovich N. , Kolchugin A. , Brouzgou A. , Bronin D. , Plaksin Sergey Vladimirovich , Khasanov A. , Tsiakaras P. 
Published: February 2020

The development of a cathode that is stable against CO2 present in the atmosphere still remains a challenge. Over the past ten years layered perovskite La2NiO4±δ has been the subject of careful research as far as also concerns their potential use as cathodes in electrochemical devices. So far as La2NiO4±δ is a p-type conductor, appropriate acceptor doping on A-site could improve the electronic conductivity by generating extra electron holes for charge compensation. Experimental results reveal that the electronic conductivity does indeed increase with a certain amount of Sr or Ca-doping. However, the substitution of La by alkali-earth elements deteriorates its electrochemical activity due to a decrease in the sub-stoichiometric oxygen amount in the structure and ionic component of conductivity [1]. One way to increase ionic conductivity is development of composite electrodes with ionic conductor as a second component, usually CeO2-based electrolyte [2]. The composite electrodes with proton-conducting electrolyte, especially in case when such electrodes are proposed to be used in contact with this electrolyte, could provide more extended area of electrochemical reaction.
The actual work focuses on the electrochemical performance of the La1.7Ca(Sr)0.3NiO4-based composite cathode materials with Ce0.8Sm0.2O1.9 (SDC) and BaCe0.89Gd0.1Cu0.01O3 (BCGC) ceramic component (in wight ratio 1:1) which were applied as a functional layer in two-layered electrodes with 98 wt.% LаNi0.6Fe0.4O3 + 2 wt.% CuO LаNi0.6Fe0.4O3 and 99.4 wt. % La0.6Sr0.4MnO3 + 0.6 wt.% CuO as a collector layer. Studies by impedance spectroscopy were performed in contact with BCGC and BaCe0.5Zr0.3Y0.2O3 + 1 wt.% CuO (BCZY) proton-conducting electrolytes in comparison with traditionally used 50 wt.% La0.6Sr0.4Fe0.8Co0.2O3 + 50 wt.% SDC and 50 wt.% La0.75Sr0.2MnO3 + 50 wt.% SSZ composite electrodes.

Keywords: La1.7Ca0.3NiO4, cathode, electronic conductivity, proton-conducting electrolyte

Acknowledgments

The authors are grateful for the financial support to: the Ministry of Education and Science of the Russian Federation (Mega-grand contract no. 14.Z50.31.0001), the Russian Foundation for Basic Research (grants no. 13-03-00065, 14-03-00414) and the Russian Foundation for Basic Research (grants no. 13-03 96098 and 14-03-00414).

References

[1] E.Yu. Pikalova, N.M. Bogdanovich, A.А. Kolchugin, D.A. Osinkin, D.I. Bronin, Electrical and electrochemical properties of La2NiO4+
δ-based cathodes in contact with Ce0.8Sm0.2O2-
δelectrolyte, accepted in Procedia Engineering
[2] B.L. Kuzin, N.M. Bogdanovich, D.I. Bronin et al, Elecrochemical Properties of Cathodes Made of (La,Sr)(Fe,Co)O3Containing Admixtures of Nanoparticles of Cupric Oxide and Intended for Fuel Cells with A Solid Electrolyte Based on Ceric Oxide, Rus. J. Electrochem. 43 (2007) 920.
Materials Search of Perovskite Cathode in SOFC by Statistical Analysis
Authors: Hwang Jaekyun , Ando Yasunobu , Watanabe Satoshi 
Published: February 2020

Solid oxide fuel cell (SOFC) technology requires further maturations to become commercialized broadly. Many existing problems are expected to be solved by intermediate temperature SOFC (IT-SOFC). On the other hand, electrochemical resistances of cathode materials increase rapidly at lower temperature. So it is necessary to understand the underlying mechanisms of oxygen reduction reaction and develop new materials. Although many experimental and theoretical researches for this purpose are in progress, traditional trial-and-error materials search must be inefficient and take too long time.
Considering the above situation, we explore critical factors that can explain the oxygen exchange rate of perovskite oxide cathode in SOFCs. It has been said that the bulk ionic conductivity is strongly related to the oxygen exchange rate, while the electronic conductivity is not as far as it is high enough. However, we found that the combination of ionic and electronic conductivities shows much stronger correlation than ionic conductivity alone while analyzing reported experimental data on 18 materials in figure 1. Materials which have high oxygen exchange rate can be explained by the multiplication of bulk ionic conductivity and electronic conductivity while others explained by the ionic conductivity.
Fig. 1 Relationship between oxygen exchange rate and bulk electronic conductivity, ionic conductivity, and the model function with both conductivities.

Figure 1
LiCoO2 -Based Composite Cathode with PO4-O2 Hybrid Framework for Lithium Ion Batteries
Authors: Min Sul Hee , Jo Mi Ru , Kang Yong-Mook 
Published: February 2020

In recent decades, lithium-ion batteries have become the most widely used power source for portable electronic devices and hybrid electric vehicles (HEVs) and plug-in HEVs because it can offer high energy and power density. The most representative cathode material for commercial Li-ion batteries is LiCoO2 due to its high capacity and excellent cycle life. LiCoO2 has the hexagonal α-NaFeO2 phase consisting of the layered rock-salt structure with the order of Li+ and Co3+ on alternating (111) planes in its cubic structure. When a Li/Li1-xCoxO2 cell is typically charged within limited composition range (0 < x < 0.5, 4.2V), it shows reasonably good capacity retention. However, the discharge capacity under the cut-off voltage of 4.2 V is around only 140 mAh/g, which is much lower than the theoretical value (274 mAh/g) of LiCoO2. Unfortunately, the practical use of LiCoO2 has been limited because its stability could be rapidly deteriorated at potentials higher than 4.2 V. Some research groups have reported that the poor cycling performance above 4.2 V is caused by structural instability induced by a phase transition from hexagonal phase to a monoclinic phase, which accompanies a volume change of ~2.6 % along the c-axis. To overcome the above problems, many researchers have developed lots of surface modifications that can improve the structural stability of LiCoO2.
In this study, we tried to control the interlayer distance variation (lattice parameter c) though the substitution of phosphorus for Li+ sites by a phosphidation process. As a result, the unwanted phase transition could be suppressed by the existence of PO4 framework formed on the surface of LiCoO2 dramatically improving the cycleability and rate capability of LiCoO2 even above 4.5 V. Using this approach, we could easily change the surface O2-framework of LiCoO2 to PO4-framework. Consequently, phosphidated LiCoO2 came to retain very high structural stability and a stable surface film was formed in contact with electrolyte during charging/discharging. Phosphidated LiCoO2 exhibited greater bulk and surface stability compared to pristine LiCoO2 even in high voltage range, suggesting that this methodology will be also promising for other high-voltage cathode materials in lithium ion batteries.
In-Operando Electrochemical-Surface Plasma Resonance (EC-SPR) Observation to the Kinetic Study of Solid Electrolyte Interface (SEI) Formation on Lithium Ion Battery
Authors: Wang Fu-Ming 
Published: February 2020

A novel in-operando observation to the formation of solid electrolyte interface (SEI) has been developed. This research demonstrates that the electrochemical-surface plasma resonance (EC-SPR) is able to evaluate the step-by-step kinetic molecule interaction between the electrolyte and the surface of electrode material. In this study, a commercial electrolyte (1M LiPF6 into EC/EMC) has been used to define the SEI formation on gold (Au) electrode. Fig. 1a shows the linear sweep voltammogram (LSV) spectrum was operated at the scanning rate of 0.83 mV/s and in the operation window of 0~(-3) V. This result confirms that the SEI was formed at -1.24V and the lithium ion was going to reduce at -3V, indicating there are at least two passivation processes on this system. Fig. 1b shows a decreasing behavior of intensity difference of SPR, indicating the substances gradually covered for the Au electrode’s surface. In accordance with Fig. 1b, this spectrum can be simply separated by two slopes. The two slopes cross a point at 21.5 min, representing the reduction time of SEI. Fig. 1c also illustrate a decreasing behavior of the angle difference of incidence, indicating a continually dissociation process was taking place. However, three different slopes were discovered and strongly correlated to the result in Fig. 1b. The first slope in Figs. 1b and 1c indicate the lithium ions dissociate from ethylene carbonate (EC) molecules and moves to the Au surface when the electrochemical driving force was triggered. The second slope in Figs. 1b and 1c implies an association process (a stable intensity in Fig. 1b and a lower slope in Fig. 1c), indicating that the lithium ion joins the SEI formation at typical reduction potential on Au surface. However, Fig. 1c reveals that the Au electrode is not able to correlate the SEI formation due to the slope changes into higher value (third slope), which represents the intrinsic property of Au is different to graphite [1], implying the SEI is further dissociated from Au surface. The SEI formation on typical electrode materials such as graphite, graphene, and silicone are under researching. The EC-SPR is a powerful instrument for studying the SEI in order to character an in-operando interaction mechanism between the electrolyte molecules and electrode materials.
Fig. 1 In-operando EC-SPR observations of (a) the LSV, the sensograms of (b) the intensity difference of SPR, and (c) the angle difference of incidence.

Reference

[1] S. S. Zhang, J. Power Sources 162 (2006) 1379.

Figure 1
Application of Graphene-Based Electrodes in Lithium-Ion Battery
Authors: Agostini Marco , Hassoun Jusef 
Published: February 2020

The recent widespread of electric (EVs) and hybrid vehicles (HEVs), with the final goal of reducing the greenhouse gas emission and atmosphere pollution, required efficient and clean power sources. Due to their high energy density, lithium-ion batteries are an ideal candidate as side system to store energy from renewable sources and power electric vehicles
1
. Although appropriate for the consumer electronic market, the present lithium-ion battery technology is still inadequate for the electric motion. The large diffusion of LIBs is still prevented by issues, including poor safety, high cost, restrict operating temperature range and materials availability. Improvements in energy density and safety, as well as reduction in cost, are mandatory steps to meet the EVs and HEVs severe targets
2
. Among the issues of LIBs technology, low theoretical capacity of the graphite anode, i.e. 372 mAh g-1, represents a limiting parameter. Indeed, great attention is now focusing on the study of alternative anode material such as Sn (994 mAh g-1), Si (4200 mAh g-1) or SnO2 (782 mAh g-1), however their application is still limited by the large volume changes upon lithium alloying-de-alloying processes. Recently, the suitability of the graphene as negative electrode in replacement of the commercial graphite anode has been demonstrated. Graphene-based electrodes have the possibility to accommodate increased amount of Li-ions in respect to common graphite
3
, thus allowing a capacity value two to three times higher in respect to graphite. Herein, we report the use of different types of graphene-based electrodes in lithium-ion cell.
[1] M. Armand and J.M. Tarascon, Nat. 2008, 451, 652.
[2] B. Scrosati, J. Garche, J. Power Sources 2010, 195, 2419.
[3] J. Hassoun, F. Bonaccorso, M. Agostini, M. Angelucci, M.G. Betti, R. Cingolani, M. Gemmi, C. Mariani, S. Panero, V. Pellegrini, B. Scrosati, Nano Letters 2014, 14, 4901.

Figure 1
Magnesium Ion Behavior in Ionic Liquids for Mg-Ion Power
Authors: Sutto Thomas Edward 
Published: February 2020

Our work here has focused on the behavior of Mg2+
in bis(trifluoromethane)sulfonyl imide based ionic liquids. Charge discharge behavior of both amorphous carbon and graphene have been studied vs. Mg metal as potential anode materials for a rechargeable Mg-ion based battery. Additional work has looked into oxide nanoparticles of the general format of Mg(M1M2)O2 prepared via a novel, flash solution oxidation process. Results will be presented focusing on the primary effort to develop cathode materials for Mg ion systems with high reversibility and capacity.

Figure 1
Optimization of Process Parameters during Solid State Synthesis of LiMn2O4 as Cathode Material for Lithium-Ion Batteries
Authors: van Holt Désirée , Sun Ruoheng , Hoffmann Anja , Eurich Svitlana , Jakes Peter , Schierholz Roland , Granwehr Josef , Kungl Hans , Eichel Rüdiger-Albrecht , de Haart L.G.J. 
Published: February 2020

One focus of the present research of Lithium-Ion Batteries is the development of higher energy and higher power density materials. Spinels like LiMn2O4 exhibit a potential of 4.1 V v.s. Li/Li+ that can be further increased by substitution of Mn by transition metals like Ni. Those substituted spinels like LiMn1.5Ni0.5O4 are highly interesting cathode-materials for the high-energy range up to 5 V. The synthesis of spinels via a solid state route enables the production of high amounts up to 100 g with inexpensive starting materials and a combined step for milling and homogeni­zation of the raw materials. However, the solid state synthesis is a challenging approach regarding an adequate homogenization and a potential eva­po­ra­tion of Li during calcination[1].
The present work aims the characterization of calcined cathode-materials to control the processing parameters in order to prepare single-phase spinel materials. Therefore, different compositions of LixMn2O4 have been synthesized from Li2CO3 and MnO2 as starting materials, applying different milling parameters and calcination conditions. The calcined powders were then characterized by powder diffraction (XRD) and electron-paramagnetic-resonance spectroscopy (EPR). It is known that Li2MnO3 might be formed during the calcination process as an undesirable lithium-rich secondary phase[2]. Thus, particular attention has been paid on this phase. The formation of Li2MnO3 may occur by non-homogeneous mixing or remaining coarse particles of Li2CO3 in the powder mixture. The EPR is a highly sensitive method to obtain even small amounts of Li2MnO3 besides LiMn2O4in the calcined product and is therefore highly interesting for this application.
[1] Y. Lee, The Effects of Lithium and Oxygen Contents Inducing Capacity Loss of the LiMn2O4 Obtained at High Synthetic Temperature, Journal of Electroceramics, 9, 209 – 214, 2002.
[2] V. Massarotti et al., Stoichiometry of Li2MnO3 and LiMn2O4 Coexisting Phases: XRD and EPR Characterization, Journal of Solid State Chemistry, 128, 80 – 86, 1997.
Fully-Reversible Solid-State Li-Ion Rechargeable Battery Composed of Positive and Negative Electrodes with the Same Active Material
Authors: Baba Mamoru , Ye Rongbin , Ohta Koji 
Published: February 2020

In this paper, we found out for the first time that the fully-reversible solid-state Li-ion rechargeable battery composed of positive and negative electrodes with the same active material Li2Mn2O4. It should be noted that the present novel reversible operation is observed because of the solid-state Li-ion battery. It will be expected that such a reversible battery is expected to be refreshed on the backward stage, when the RiLiB battery has run down at last on the forward stage,
Investigating the Surface Segregation of Perovskite Thin Films to Optimise the Redox Behaviour for Application in Metal-Air Batteries
Authors: van den Bosch Celeste Anna Maria , Harrington George Frederick , Skinner Stephen J. , Aguadero Ainara 
Published: February 2020

It is essential to improve energy storage in tandem with developing renewable energy alternatives as an intrinsic challenge of renewable energy sources is irregular power production. Currently oxygen evolution and oxygen reduction are two key electrochemical reactions which limit the efficiency of energy storage devices including metal-air batteries. Hence, improving these reactions would greatly benefit the development of a renewable energy economy.
It has previously been demonstrated that the perovskite La0.5Sr0.5Co0.5Mn0.5O3-
δ (LSCM) [1] can reversibly accommodate both a fully oxidised phase (δ = 0) and a reduced phase (δ = 0.62), making this the most hypo-stoichiometric simple perovskite reported to date (Figure 1). The oxygen vacancies introduced as a result of this variable stoichiometry as well as the potential range of transition metal oxidation states make this material an ideal candidate to investigate as a redox mediator for oxygen reduction and evolution reactions.
The ability to tune and control the defect structure of this system will allow optimisation of the electrochemical behaviour. With this is mind, LSCM thin films of 10 – 75 nm thick have been prepared by pulsed laser deposition with initial x-ray diffraction results indicating a change in lattice structure depending on the substrate the films are deposited on likely due to strain effects [2].
Since the surface characteristics are fundamental factors that governs the activity of these materials, further characterisation of the films included low energy ion scattering (LEIS) to consider segregation effects (Figure 2) [3], atomic force microscopy and x-ray photoelectron spectroscopy to determine changes in transition metal oxidation state. The redox activity of LSCM under different polarisation conditions has been investigated with isotopic labelling through secondary ion mass spectroscopy [4].
A systematic study of the La0.5Sr0.5Co0.5Mn0.5O3-
δ thin films has shown that we can control the cell parameters of LSCM by growing thin films on different substrates. The LEIS measurement revealed that the induced strain may be affecting the surface termination and hence, may be instrumental in optimising the electrochemical behaviour of the perovskite.

Figure
1 – Thermogravimetric analysis of La0.5Sr0.5Co0.5Mn0.5O3-δ

Figure 2 – Comparison of the elemental composition of La0.5Sr0.5Co0.5Mn0.5O3-δ thin films on lanthanum aluminate (LAO, left) where in-plane compressive strain is expected and magnesium oxides (MgO, right) substrates where tensile strain of the thin films is expected

[1] A. Aguadero, et. al., Angew. Chem. Int. Ed. Engl., 2011, 50, 6557–61.
[2] M. Kubicek, et. al., ACS Nano, 2013, 7, 3276–86.
[3] J. Druce, et. al., Solid State Ionics, 2014, 262, 893–896.
[4] J. A. Kilner, et. al., J. Solid State Electrochem., 2011, 15, 861–876.

Figure 1
New Generation High Performance Lithium-Ion Capacitor Laminate Cells
Authors: Cao Wanjun , Chen Xujie , Shih Jonathan , Zheng Jim P. 
Published: February 2020

In recent years considerable research has been focused on the development of high energy density EC capacitors. Among all the energy storage systems that have been investigated and developed in the last few years, Lithium-ion Capacitors (LICs) have emerged to be one of the most promising because LICs achieve higher energy density than conventional Electric Double-Layer Capacitors (EDLCs), and better power performance than Li-ion batteries (LIBs) as well being capable of long cycle life which is shown in Fig. 1. LICs contain a pre-lithiated LIB anode electrode and an EDLC cathode electrode. Previously, we have reported a LIC with activated carbon (AC) cathode and hard carbon (HC)/stabilized lithium metal powder (SLMP) anode electrodes with high energy density, high power density and long cycle life1-7. From all the study before, we have achieved a high energy density LIC pouch cell4 with an energy density as high as 30 Wh kg-1 but only with a usable specific power of about 1.0 kW kg-1 and a maximum specific power of 2.0 kW kg-1. Therefore in this paper, we wish to report new generation high performance LIC laminate cells with higher power density and longer cycle life by sacrificing the energy density of the cells. The low temperature performance of the LIC laminate cells is also included in this paper. It can be concluded from the following data figures (from Fig. 2 to Fig. 4) that the specific energy and energy density as high as 20 Wh kg-1 and 38 Wh L-1 have been achieved, respectively. The laminate cells obtained a maximum specific power of 7.8 kW kg-1, respectively. The developed LICs can operate in a temperature as wide as from -40 degree C to +70 degree C. After 50,000 cycles, the LIC laminate cells still have 92% of the initial discharge capacity.
References:
1. J.P. Zheng and W.J. Cao, The 20th International Seminar on Double Layer Capacitors and Similar Energy Storage Devices, Florida Educational Seminars Inc. (2010).
2. W.J. Cao, J.P. Zheng, J. Power Sources, 213, (2012) 180.
3. W.J. Cao and J.P. Zheng, J. Electrochem. Soc. 160, (2013) A1572.
4. W.J. Cao, J. Shih, J.P. Zheng, T. Doung, J. Power Sources, 257, (2014) 388-393.
5. W.J. Cao, Y.X. Li, B. Fitch, J. Shih, J.P. Zheng, J. Power Sources, 268, (2014) 841-847.
6. W.J. Cao, J.S. Zheng, D. Adams, T. Doung and J.P. Zheng, J. Electrochem. Soc., 161(14), (2014) A2087-A2092.
7. W.J. Cao, M. Greenleaf, Y.X. Li, D. Adams, M. Hagen, T. Doung, J.P. Zheng, J. Power Sources, 280, (2015) 600-605.

Figure 1