bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Plenary) U.S. DOE EERE Activities in High Temperature Electrolysis and Reversible Fuel Cells
Authors: Peterson David , Stetson Ned , Papageorgopoulos Dimitrios , Gibbons William T , Randolph Katie 
Published: July 2021

The Hydrogen and Fuel Cell Technologies Office (HFTO) within the U.S. Department of Energy’s (DOE) Office of Energy Efficiency and Renewable Energy (EERE) supports a range of solid oxide-based research, development, and demonstration efforts that fall under the areas of high temperature electrolysis (HTE) and reversible fuel cells (RFCs). These efforts range from earlier stage R&D on cell components to demonstrating early system technology. Particularly when used in conjunction with high temperature process heat, HTE technology shows promise for highly efficient, cost effective, sustainable hydrogen production at high volumes. This potential has led to its inclusion in multiple HFTO initiatives, including two national lab-led consortia. HTE is one of four pathways being supported under DOE’s HydroGEN Energy Materials Network (EMN) Consortium on Advanced Water Splitting Materials (AWSM) for H2 production. The HydroGEN EMN offers an extensive collection of materials research capabilities at 5 core national laboratories for addressing AWSM R&D challenges in efficiency, durability, and cost. HydroGEN focuses on next generation materials including proton conducting ceramics and metal-supported cell architecture for HTE. H2NEW (H2 from Next-generation of Electrolyzers of Water) is a recently launched national lab consortium focused on overcoming technical barriers to enable affordable, durable, and efficient low- and high-temperature electrolyzers to achieve <$2/kg hydrogen production. Unlike HydroGEN, the emphasis is not on new materials development but on addressing components, materials integration, and manufacturing R&D. Durability is the most critical, initial focus of the H2NEW HTE effort.
HTE also has a role in DOE’s H2@Scale energy system vision. This initiative is bringing together diverse stakeholders to advance affordable wide-scale hydrogen production, transport, storage, and utilization to unlock revenue potential and value across multiple sectors and applications. The use of low-cost electricity to affordably split water into hydrogen and oxygen is central to implementation of the H2@Scale concept. Reversible fuel cells also have a role in H2@Scale as well as DOE’s Energy Storage Grand Challenge as a promising technology for long duration energy storage. RFC stack and system technical targets to help guide ongoing and future R&D efforts were recently developed. In addition to an overview of these initiatives including the role solid oxide technologies will play, highlights of HFTO-supported R&D and analysis work from the cell to system level for both HTE and RFCs will be provided.
In-Situ Measurement of Residual Stress in Solid Oxide Fuel Cells
Authors: Yashiro Keiji , Komaya Takumi , Ruhma Zaka , Watanabe Satoshi , Sato Kazuhisa , Kawada Tatsuya 
Published: July 2021

Introduction

Solid oxide fuel cells (SOFCs) are attracting attention as highly efficient energy conversion devices. However, durability and mechanical reliability are issues. To improve durability and mechanical reliability, it is essential to evaluate the residual stress generated in the constituent materials, especially the residual stress generated in the electrolyte. While residual stress is measured by various methods, the optimum measurement method has not been established yet. The purpose of this study is to evaluate the residual stress of the cell using in-situ cosα method, which has an advantage in measurement speed and easy handling.

Experiment method

High-temperature x-ray stress measurement was performed as a quantitative evaluation method for mechanical behaviors. A portable X-ray residual stress measuring device μ-X360s manufactured by Pulstec Industries was used. The cos α method, which is faster and easier than the sin2ψ method, was used for high-temperature X-ray stress measurement. In the cosα method, the Debye ring is acquired by a two-dimensional detector, and the stress is calculated from the difference between the stress-free Debye ring and the Debye ring of the measurement sample. High temperature chamber was designed and prepared for high temperature x-ray stress measurement. A capton film is used to separate outside and measurement atmosphere. In addition, the measurement position can be adjusted by moving stage.
Commercial sofc cells (Ningbo SOFCman cell and Elcogen) were used to compare the residual stress during the various operation procedures.

Results and discussion

Fig. 1 shows the difference in change in residual stress of YSZ electrolyte depending on the structure of the anode. Anode of Ningbo SOFCman cell has small porosity, while anode of Elcogen cell has large porosity. We measured changes in residual stress during heating, anode reduction, and reoxidation processes.
The Elcogen cell was reduced much faster than Ningbo cell, because hydrogen gas can diffuse more easily in anode due to higher porosity. Therefore, residual stress of Elcogen cell steeply changed after hydrogen introduction. Then, the residual stresses after anode reduction were completely different in these two cells at room temperature. Compressive stress of 800 MPa remained in the electrolyte of Ningbo cell. On the other hand, less compressive stress of 400 MPa remained in the electrolyte of Elcogen cell. The temperature dependence of residual stress is also different in the two cells. The deformation of the cell after reoxidation was also completely different. Ningbo cell was deformed convexly toward the anode side, although Elcogen cell was hardly deformed. The difference may come from the difference in porosity of anode.
Fig. 1 Circumferential residual stress of YSZ during reoxidation heating in 20％O2-N2 and SEM images of anode structures.

Figure 1
Deconvolution of Gas Diffusion Polarization in Ni/Gadolinium-Doped Ceria Fuel Electrodes
Authors: Grosselindemann Cedric , Russner Niklas , Dierickx Sebastian , Weber Andre 
Published: July 2021

Electrochemical impedance spectroscopy and the subsequent impedance data analysis by the distribution of relaxation times (DRT) represent a powerful method to unfold electrochemical processes in solid oxide cells. This approach has been successfully demonstrated for electrolyte [1, 2] as well as anode-supported [3] solid oxide cells exhibiting a nickel / yttria-stabilized zirconia (Ni/YSZ) fuel electrode. Applying this methodology, all physicochemical loss processes occurring in the cells could be identified by their relaxation frequencies and subsequently quantified by means of CNLS-fitting.
However, in the case of cells exhibiting a Ni/Gadolinium-doped ceria (Ni/CGO) fuel electrode, an unambiguous process assignment in the DRT has not been feasible up to now, since the charge transfer and gas diffusion overlap in the spectrum [4, 5]. The latter is caused by the oxygen non-stoichiometry of CGO, which results in a large chemical capacity, shifting the relaxation frequency of the charge transfer process towards lower relaxation frequencies. The resulting overlap of charge transfer and gas diffusion process in the spectrum impedes a direct deconvolution of these two processes [6].
Facing this challenge, we here present a solution of isolating and quantifying the gas diffusion process at the fuel electrode with the help of ternary fuel mixtures exhibiting different gas diffusion coefficients. The gas diffusion coefficients of hydrogen and steam were altered by changing the inert gas component between nitrogen and helium respectively. As the two gas mixtures exhibit identical reactant and reaction product concentrations, the charge transfer polarization is not affected. The differences in polarization resistance R
pol, which become visible in figure 1, are solely caused by the differences in gas diffusion polarization [2].
In this contribution the detailed procedure to quantify the gas diffusion polarization and an effective gas transport parameter predicting the gas diffusion resistance for arbitrary fuel mixtures are introduced. Furthermore, the applicability of this approach for the parameterization of a zero-dimensional cell model [3] for a solid oxide cell with Ni/CGO fuel electrode will be presented.

References:

[1] Schichlein et al., J. Appl.
Electrochem., 32, 875 (2002).
[2] Sonn et al., J. Electrochem.
Soc., 155 (7), B675 (2008).
[3] Leonide et al., J. Electrochem.
Soc., 155 (1), B36 (2008).
[4] Weber et al., ECS Trans., 77 (10), 141-147 (2017).
[5] Riegraf et al., ChemSusChem, 10, 587 (2017).
[6] Riegraf et al., J. Electrochem.
Soc., 166 (13), F865 (2019).
Figure 1: (a) Nyquist-plot and (b) DRT of the impedance spectra of two ternary gas mixtures with the inert gases nitrogen and helium respectively (T = 852 °C, OCV-conditions, gas composition: 0.1 atm H2, 0.05 atm H2O, 0.85 atm inert gas).

Figure 1
Effect of Fuel Depletion on Ni-YSZ Anode Supported Membrane Fuel Cell Under Different Discharge Modes
Authors: Lv Zhe , Huang Xiaoying , Liu Xin 
Published: July 2021

Declining performance and service life are important factors restricting SOFC commercial applications. It is necessary to study the influencing factors of material selection, preparation process, operation parameter and failure. During the long-term operation, local gas path failure may lead to insufficient or depletion of fuel gas supply, which may lead to the decline of battery performance or failure directly. During the discharge period, there are two possibilities: gas depletion in a cell unit in stack or in a local region of one cell. In this work, button single cells with Ni-YSZ (anode support)|YSZ (film)|GDC (buffer layer)|LSCF (cathode) structure by mass-producing under industrial conditions were operated with dry hydrogen as fuel. The experiments of fuel gas depletion were carried out by constant current and constant voltage discharge modes to simulate single cell unit failure in series stack and local region failure of one cell. The results show that during constant current discharge, the terminal voltage decreased rapidly and even appeared negative voltage after cutting off the H2 supply. When the H2 was refueled, voltage could rise quickly or even exceed the initial value. However, as the hydrogen was cut off and the constant current was maintained, the performance of the single cell decreased significantly, and the open circuit voltage and maximum power density decreased sharply, which was due to the damage of the cell caused by the anode Ni oxidation-reduction cycles, and cracks appeared on the electrolyte membrane. By contrast, no matter how long the fuel supply was cut off, the single cell performance in constant voltage discharging mode didn’t decline significantly, which indicates that maintaining a reasonable cell terminal voltage can avoid the Ni oxidation in anode caused by fuel depletion. Finally, we conclude that the long time fuel depletion of the cell unit may directly destroy the cell and affect the stack life, while the local fuel depletion of a certain cell will not cause its damage.
References
1. M. H. Tran, B. J. Park, H. H. Yoon, J. Colloid Interface Sci., 578, 641-649 (2020).
2. N. Wongsawatgul, S. Chaianansutcharit, K. Yamamoto, et al, Ceram., 3 (1), 114-126 (2020).
3. H. J. Cho, G. M. Choi, Solid State Ion, 180, 792-795 (2009).
4. Z. R. Wang, J. Q. Qian, S. R. Wang, et al, Solid State Ion, 179, 1593-1596 (2008).

Figure 1
Investigating Effects of Operational Parameters on the Rate of Electrochemical Cleaning of Chromium Deposits on Strontium-Doped Lanthanum Manganite Cathodes in Solid Oxide Fuel Cells
Authors: Sugimoto Michelle , Zhu Zhikuan , Gopalan Srikanth , Basu Soumendra , Pal Uday 
Published: July 2021

Chromium poisoning of the cathode remains a significant obstacle to the long-term performance of solid oxide fuel cells. Previously, a quick, easy method was introduced that requires no material modifications, major thermal cycling, nor exposes the cell to any species it does not already encounter during operation. The method, electrochemical cleaning, reverses the electrochemical deposition reaction of chromium-containing species by applying a mild anodic bias. Chromium vapor species are formed, freeing active sites in the cathode. The method has been shown to completely recover cell performance via this current-voltage technique.
The present work investigates the mechanism of electrochemical cleaning by assessing the effect of various operating parameters on the rate of chromium removal. Using a design of experiments method, eight cells were poisoned and then cleaned using differing combinations of the following cleaning parameters: cell temperature, air humidity, anodic current density, and fuel humidity. Regression analysis of two comparative metrics, cell performance via current voltage curves and post-test chromium content determined via Energy Dispersive Spectroscopy, demonstrated that cell temperature has the highest effect on the rate of chromium removal, followed by air humidity. A refined parameter space for future study is proposed for further optimization of the parameters. Previously, the electrochemical cleaning method was shown to be effective in the removal of Cr2O3 deposited species, but not Cr-Mn spinel deposits. The effects of operating parameters on the removal of the two different types of Cr deposits is discussed. An additional process for the removal of Cr-Mn spinel is demonstrated, which again makes use of the cell operating parameters. Together, the two methods present a facile, periodic process to greatly extend solid oxide fuel cell lifetime.
Commercialization of the Ceres Power SteelCell® Technology: Latest Update
Authors: Leah Robert , Bone Adam , Selcuk Ahmet , Lankin Mike , Rahman Mahfujur , Clare Andy , Reade Gavin , Felix Florence , De Vero Jeffrey , Wang XIn , Mukerjee Subhasish , Selby Mark 
Published: July 2021

Ceres Power continues to acquire commercial partners for its low-temperature metal supported SteelCell® SOC technology 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, significant commercial developments have taken place, rapidly progressing genuine mass-market adoption of SteelCell® technology for power generation. Two major OEM partners, Robert Bosch GmbH in Germany and Doosan Fuel Cell in South Korea now have licenses to manufacture SteelCell® cells and stacks with a full technology transfer from Ceres, with a commitment to volume manufacturing. Doosan is initially building a 50MW/y manufacturing plant with potential to extend that further in future. This complements Ceres’ own manufacturing facility in Redhill, UK which is fully operational with an expandable capacity of 2MW/y to meet demand from other customer demonstration programs.
Other active customer programs include the successful ongoing commercial launch of a 4.2kWe CHP system by Miura in Japan and the development of a 30kWe range extender for electric buses by Weichai Power in China.
Another significant commercial development is Ceres Power agreeing a strategic partnership with AVL in Austria to combine engineering expertise and knowhow in fuel cell system development and conduct joint R&D, which will enable the incorporation of SteelCell® technology into new applications. The first agreement has already been signed with an unnamed customer.
As part of a drive to broaden the applicability of SteelCell® technology and play a larger part in the rapidly developing green hydrogen economy, a major program has been initiated to evaluate and develop SteelCell® technology for steam electrolysis and the potential production of E-fuels.
All of these developments are rapidly bringing about the full commercialization of SOC technology as a significant contributor to the evolving net zero energy sector.
Assessing the Performance and Degradation of Metal Supported SOFCs Operating with Natural Gas
Authors: Welander Martha M , Tucker Mike C 
Published: July 2021

High operating temperatures endow SOFCs with many advantages including fuel flexibility and high conversion efficiencies, distinguishing them from many other types of fuel cells. In order to leverage this role SOFCs must be able to operate well with a variety of fuels including H2, CH4, natural gas, syngas, and higher molecular weight hydrocarbons. This requirement necessitates keeping the SOFC anodes clear from excessive carbon deposition or “coking” when exposed to hydrocarbon fuels. Standard SOFC anodes composed of a Ni-YSZ cermet are highly susceptible to coking which can be detrimental to overall cell performance as it can block catalytic sites and impede gas transport. One way to mitigate this effect is to introduce steam into the fuel feed to remove carbon via oxidation. However, steam also risks oxidizing the catalytically active Ni metal resulting in volume changes that may damage the fragile electrode microstructure, requiring material or mechanical solutions to improve overall cell resilience. LBNL has developed metal supported SOFCs (MS-SOFCs) with unique symmetrical architecture and infiltrated catalysts with numerous advantages over conventional cells including low cost, mechanical ruggedness, quick start-up capability, and excellent tolerance to redox cycling and thermal cycling under standard H2 conditions. The high mechanical stability of LBNL’s MS-SOFCs suggest that they may be well suited for long-term hydrocarbon operation, even when high levels of steam are present in the fuel stream.
In this work, the use of LBNL’s MS-SOFCs are extended to natural gas. As the least carbon-intensive fossil fuel, natural gas has the potential to serve as a bridging fuel, facilitating the transition into a low carbon energy economy. The durability of the MS-SOFCs under natural gas and reformate fuels have been evaluated at 700 °C as well as the resilience toward thermal cycling under equivalent fuel conditions to demonstrate the feasibility of using the cells in applications that require rapid start/stop cycles (with ramp rates <15 minutes). These experiments suggest that cell exposed to natural gas reformates operate and degrade in a similar manner to cells operating with pure H2 and have high tolerance to repeated thermal cycling. Cells operating with natural gas under internal reformate conditions experience faster degradation rates and the ability to improve the performance of these cells with a high entropy alloy catalyst will be discussed. Ongoing experiments will examine durability of the MS-SOFCs to reformate and natural gas fuels with sulfur contamination in order to determine the effect of carbon species present in the fuel stream on sulfur reactions at the electrode. This talk will give an overview of the current status of LBNL’s MS-SOFC technology operating with natural gas fuel and reformates, the effect of sulfur poisoning, resilience to thermal cycling, as well as determine future improvements required for improved cell performance and commercialization.
Electrical Energy Storage Using Hydrogen Storage Alloy Coupled Proton-Conducting Reversible Solid Oxide Cell
Authors: Chen YanBo , Shi Yixiang , Cai Ningsheng 
Published: July 2021

Proton-conducting reversible solid oxide cell (RSOC) can efficiently store intermittent renewable energy in the form of hydrogen. The cell can operate in either SOFC mode or SOEC mode and achieve efficient and low cost energy storage. The RSOC needs a hydrogen storage equipment to reach enough energy storage capacity.
In this study, a hydrogen storage alloy coupled proton-conducting reversible solid oxide cell is developed and functions as rechargeable battery. Experiments are performed at 500-650℃ using a Ni-BCZY/BCZY(BaCe0.5Zr0.4Y0.1O3)/LSM-BCZI micro-tubular cell and Zr-based hydrogen storage alloy. The hydrogen production and electrochemical performance are studied with different operating conditions and amount of hydrogen storage alloy. The current density ranges from -970A/m2 to -1230A/m2 for the SOEC mode, and from 960 A/m2 to 1300 A/m2 for the SOFC mode at a polarization voltage of 0.1 V with different gas compositions and temperatures. The hydrogen storage ranges from 0.4wt% to 1.4wt%.
To further optimize the hydrogen storage alloy coupled RSOC, a muti-scale and muti-physics two-dimensional (2D) micro-tubular RSOC model is developed. This model couples the electrochemical reaction, charge transfer, mass transfer, momentum transfer, heat transfer as well as the parameters of microscale porous electrodes and the hydrogen alloy. The model is validated by the experimental data obtained above. The simulation results shows that the cell’s capacity and round trip efficiency are dependent on the amount of hydrogen storage alloy utilized. The energy capacity increases while the roundtrip efficiency decreases with increasing alloy utilization. A practical strategy to operate the new battery is to maintain a low alloy utilization and get a required storage capacity as well as a high efficiency. The model is demonstrated an useful tool for the design and optimization of the hydrogen storage alloy coupled RSOC.
Epstein–Barr Virus–Encoded Circular RNA CircBART2.2 Promotes Immune Escape of Nasopharyngeal Carcinoma by Regulating PD-L1
Authors: Ge Junshang , Wang Jie , Xiong Fang , Jiang Xianjie , Zhu Kunjie , Wang Yian , Mo Yongzhen , Gong Zhaojian , Zhang Shanshan , He Yi , Li Xiayu , Shi Lei , Guo Can , Wang Fuyan , Zhou Ming , Xiang Bo , Li Yong , Li Guiyuan , Xiong Wei , Zeng Zhaoyang 
Published: July 2021

Abstract

Epstein–Barr virus (EBV) infection is an established cause of nasopharyngeal carcinoma (NPC) and is involved in a variety of malignant phenotypes, including tumor immune escape. EBV can encode a variety of circular RNAs (circRNA), however, little is known regarding the biological functions of these circRNAs in NPC. In this study, EBV-encoded circBART2.2 was found to be highly expressed in NPC where it upregulated PD-L1 expression and inhibited T-cell function in vitro and in vivo. circBART2.2 promoted transcription of PD-L1 by binding the helicase domain of RIG-I and activating transcription factors IRF3 and NF-κB, resulting in tumor immune escape. These results elucidate the biological function of circBART2.2, explain a novel mechanism of immune escape caused by EBV infection, and provide a new immunotherapy target for treating NPC.

Significance:
This work demonstrates that circBART2.2 binding to RIG-I is essential for the regulation of PD-L1 and subsequent immune escape in nasopharyngeal carcinoma.