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High temperature electrolysis of water using solid oxide electrochemical cells (SOEC) is a promising technology for hydrogen production with high energy efficiency and may promote decarbonization when coupled with renewable energy sources and excess heat from nuclear reactors. Over the past several decades there have been extensive scientific and engineering studies on cell materials and degradation behaviors that have greatly improved current density, decreased total resistance, and lowered degradation rates. Although the technology is now at a near-commercial level, maintaining consistency in cell testing and minimizing variance in practical testing environments is an often overlooked but crucial topic. To promote high quality data collection, testing procedures and balance of plant component details are extremely important to consider. This work discusses some key factors affecting the reproducibility of practical SOEC testing on the button cell level, namely, current collection layers, cell sealing procedures, the reliability of steam and hydrogen delivery systems, cell testing fixture design, and reduction procedures. To provide a baseline and a level of standardization for the SOEC community, this work also discloses details of the standard operating procedure and techniques adopted for o-SOEC testing at Idaho National Laboratory (INL).

Accidental ingestion of foreign bodies constitutes an emergency for pediatric care services especially since the group most frequently affected consists of children between 6 months and 3 years of age. Ingestion of button cell batteries has high risks for severe early complications such as esophageal perforations and mediastinitis, as well as the long term risk of stenosis. Early identification and extraction are the most important management strategies. A double contour on a frontal cervical, thoracic, or abdominal x-ray is characteristic, but this same radiological sign has been reported for other foreign bodies. We present two cases with these characteristics. [ABSTRACT FROM AUTHOR]

In this study, a planar solid oxide fuel cells (SOFCs) apparatus with a 6 cm × 6 cm anode supported single cell based on a modified button cell was designed for operation in both regular cell and button cell configurations. The apparatus was assembled with a regular cell with an active area of 5 cm × 5 cm and with a button cell with an active area of 2.54 cm 2 . They consist of fuel and oxidant chambers that allow heat conversion and thus increase the temperatures of the fuel inlet and oxidant inlet streams. The chambers reduced the cooling effect, thereby improved the cell performance. In addition, a wire–in–tube–type heat exchanger was designed and fabricated. This device was installed in front of the fuel inlet of the SOFC apparatus to improve heat transfer to better increase the temperature of the fuel inlet stream. Results indicate that the fuel outlet temperature of the system with heat exchanger is much higher than that of the system without heat exchanger. Thus, the performance of system with heat exchanger is largely improved. This improvement means that the wire–in–tube type heat exchanger is proved to be effectively increases the hydrogen inlet temperature by enhancing heat transfer. [ABSTRACT FROM AUTHOR]

Introduction: Foreign body ingestion (FBI) is common in pediatrics and can lead to complications. The aim of the present study is to review the experience of our center in the management of these patients and to propose a treatment protocol. Material and Method: Retrospective, observational and descriptive cross-sectional study, in which the endoscopic reports and records of patients diagnosed with IFB managed by the Pediatric Endoscopy Unit of the Regional Clinical Hospital of Concepción between January 2013 and June 2017 (53 months) were reviewed, with a total of 40 cases. Data recording and analysis was performed with Microsoft® Excel 2016® for MacOS®. Results: The average age was 3,96 ± 3,24 years. The statistical fashion was 2 years. All patients underwent a upper gastrointestinal endoscopy. The most frequent FB was the coin (61,9%). In 6 opportunities (14,2%) was a button batery. FB retention was in the proximal third of the esophagus (30,9%), the gastric body (26,2%) and the distal third of the esophagus (14,2%), being extracted mainly with foreign body clamp (90,4%). The 57,5% showed some injury related to the location of the FB, being the most serious the produced by button batery. Conclusion: FBI in children is a potentially dangerous entity, so it becomes necessary to have a pediatric endoscopy unit and treatment protocols to avoid complications, especially with high-risk objects. [ABSTRACT FROM AUTHOR]

Objective: To describe the types of aural foreign bodies (FBs) among patients in Ibn Sina Teaching Hospital (ISTH) and to study the patient’s symptoms, duration, complications and procedures used to extract them.Methods: A record based descriptive study was looked at patients with aural FBs at ISTH for 5 years between 2009 and 2015. The diagnosis of aural FBs was based on personal history, and otoscopic findings. The data were obtained from the records.Results: Patients with aural FBs were 154, (age 1-70 years). Inorganic aural FBs were 100 (65%) and 54 (35%) were organic. Unilateral purulent aural discharge was in 72 (46.75%) patients, pain in 27 (17.53%), ear bleeding in 12 (7.8%), conductive hearing loss and tinnitus each was 8 (5.19%) and itching in 7 (4.55%). Duration of symptoms was <1 week in 55 (35.7%) cases, 1-2 weeks in 64 (41.6%) and 2-4 weeks in 29 (18.8%). Forceps, syringing, hook and suction were the tools used for removal of the FBs, 56 (36.4%), 40 (26.0%), 36 (23.4%), 14 (9.1%) respectively. FBs were removed under G.A. were 30 (19%). Complications were otitis externa in 38 (24.7%) cases, tympanic membrane perforation in 29 (18.85%) and external meatus laceration in 28 (18.20%).Conclusion: The most common aural FBs found were inorganic (cotton tip, stone and eraser) and organic (fly, lice and bee). Complications were unilateral purulent discharge followed by pain and ear bleeding. FBs duration was from <1 to 4 weeks. The common procedures used were forceps, syringing, hook and suction. Particularly, organic vegetative FBs were removed under general anesthesia. [ABSTRACT FROM AUTHOR]

• The power density decreases with increasing cathode diameter for the button cells. • Because the polarization resistances associated with gas diffusion process increases. • The polarization resistance also increases with increasing fuel utilization. • The power density is low for large-scale cells under high fuel utilization. Small-scale planar solid oxide fuel cells (SOFCs) with several centimeters in diameter called "button cells" or "coin cells" are widely used for fundamental research. Although the performance of large-scale cells is inferior to that of button cells, the precise reason is unclear. In the present work, electrochemical impedance spectroscopy (EIS) are performed for button cells with different cathode areas under different fuel utilization, and distribution of relaxation times analysis was conducted to deconvolute the EIS. The power density decreased with increasing cathode diameter for the button cells. The polarization resistances associated with the gas diffusion process at low frequencies increased for a cell with a large cathode area, when the gas flow path is different between the inner and outer electrode areas for the button cells. The polarization resistance related to the gas diffusion process also increases with increasing fuel utilization. As a result of simple simulation considering the Nernst loss, the power density at 0.75 V was estimated to be 0.169 W/cm2 at U f = 0.8 for a large-scall cell with dimensions of 10 × 10 cm2, which is smaller than that for a button cell with a cathode diameter of 6 mm (0.730 W/cm2 at U f = 0.04). [Display omitted] [ABSTRACT FROM AUTHOR]

This work presents hydrometallurgical routes for recovering valuable elements from spent button cells, based on leaching of internal components with sulfuric acid (Li/MnO2 and Zn-air) or nitric acid (Ag-Zn), at 90 ºC for 2h. Slow evaporation of the leachate crystallized MnSO4.H2O, whereas lithium was partially recovered as LiF. Mercury present in Zn-air and Ag-Zn samples was precipitated as HgS. Silver was recovered as AgCl before mercury precipitation. Zinc and iron were precipitated as hydroxides. The amount of iron varied according to the intensity of the corrosion of the external cell case. Final wastes are neutral and colorless sodium sulfate/nitrate solutions.

Aims Insertion of a foreign body in the nasal cavity is a very common incident in children. It is easily diagnosed, but the type of foreign body varies and extraction can sometimes be difficult, with risk of complications. The present study reports nasal foreign bodies seen in emergency in our ENT department, with an update on the state of knowledge. Materials and methods A prospective study between May and August 2011 included all patients admitted to the ENT emergency unit for nasal foreign body. Data comprised age, gender, circumstances of discovery, symptoms, type of foreign body, extraction method and complications. Results Two hundred and sixty cases of nasal foreign body were included, representing 4.3% of all consultations in the unit. Mean age was 3 years (range: 1–16 years); the sex ratio was 1.4 (male predominance). The incident was reported by a family member or the actual child in 76.9% of cases ( n = 199), or discovered following nasal symptoms in 23.1% ( n = 61). The main types of foreign body were non-organic synthetic beads in 18.8% of cases and vegetable forms in 17.7%. Extraction was easy, using forceps, micro-hooks or suction, in 91.53% of cases. Complications comprised infection ( n = 48), epistaxis ( n = 18) and nasal septum perforation ( n = 1). Conclusion Nasal foreign bodies are a frequent accident in medical practice, especially in young children. They are generally harmless, but may incur complications if overlooked or when a button cell is involved, whence the importance of timely extraction. The best treatment, however, remains prevention. [ABSTRACT FROM AUTHOR]

In order to improve the pseudocapacitance properties and cycle stability of polyaniline (PANI), reduced graphene oxide-silica (rGOS) is used to modify the polyaniline material. Ternary composites of reduced graphene oxide-silica-polyaniline (rGOSP) are prepared by chemical polymerization of aniline using ammonium persulfate oxidant with various amounts of rGOS in aq. 1 M HSO solution. Morphology analysis of rGOSP composite revealed that the nano fibers form of polyaniline is intercalated in the graphene layers and also covered the rGOS. Symmetric supercapacitor cell is fabricated in CR2032 coin cell with rGOSP composite as electrode and its electrochemical performance is evaluated from cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy techniques. rGOSP composite yielded a higher capacitance and lower ESR value compared to that of its individual components, PANI and rGOS. The energy density of the composite is found to be 10 W h kg at a power density of 2310 W kg. Furthermore, over 75.2 % of the original capacitance is retained after 6000 galvanostatic charge-discharge cycles at 0.8 A g. [ABSTRACT FROM AUTHOR]

Many household batteries worldwide still end up in landfills or are incinerated due to inefficient collection and recycling schemes. Toxic heavy metals from improperly discarded button cells pose a serious risk to human health and the environment, as they can pollute air, soil and water. This paper analyses a series of button cells selected from batteries available on the retail market, and compares their polluting potential. A total of 64 batteries were subjected to chemical analyses of 19 elements — including metals and metalloids — , and energy density measurements. The samples were from four different brands of each of the four most common button cell technologies (alkaline, zinc-air, silver oxide and lithium). An energy-normalized index — the Weighted Potential Pollution Index (WPPI) — was proposed to compare the polluting potential of the different batteries. The higher the battery WPPI score, the greater the content in toxic elements and the lower the energy output. The results of the chemical composition and energy density varied depending on the construction technology of the button cells. However, significant differences in both variables were also found when comparing different brands within the same technology. The differences in WPPI values confirmed the existence of a significant margin to reduce the environmental impact of discarded button cells simply by avoiding the most polluting options. The choice of the battery with the most favourable WPPI produced a reduction in potential pollution of 3–53% for silver oxide batteries, 4–39% for alkaline, 20–28% for zinc-air and 12–26% for lithium. Comparative potential pollution could be assessed when selecting batteries using an energy-normalized index such as WPPI to reduce the environmental impact of improperly disposed button cells. [ABSTRACT FROM AUTHOR]

Molten carbonate fuel cells (MCFC) used as active carbon dioxide concentrator units are a promising solution to reduce greenhouse gas (GHG) emissions from traditional combustion plants. The cell reaction transfers carbonate ions from the cathode to the anode and allows the fuel cell to simultaneously produce power and separate CO 2 from a stream of flue gas. Carbon dioxide separation is of high interest for use in natural gas combined cycles and coal gas combustion plants, as a large part of anthropogenic CO 2 worldwide originates from such installations. The flue gas from these types of combustion technologies typically contains 3–15% CO 2 , which is in the lower operational range of the MCFC. The aim of this work was to investigate the possibility to retrofit existing power plants with MCFC to reduce the total release of CO 2 without necessarily reducing the power output, and to understand which kind of power plant could have the major benefits with an MCFC retrofitting. The performance of lab scale MCFC fed with simulated flue gas was evaluated, and a number of operational parameters, such as utilization factor and cathode humidification were varied to study the effect on fuel cell performance. The results show that it is feasible to operate the MCFC as a CO 2 separator for simulated gas turbine flue gas; however, the voltage drop due to low CO 2 concentration may restrict the operating window depending on various operating conditions. [ABSTRACT FROM AUTHOR]

Highlights: [•] A well selected sample of 146 batteries was analysed for its heavy metals content. [•] A comparison was made between heavy metals contents in batteries in 2006 and 2011. [•] No significant change after implementation of the new EU Batteries Directive. [•] Severe differences in heavy metal contents were found in different battery-types. [ABSTRACT FROM AUTHOR]

SUMMARY A unitized regenerative solid oxide fuel cell (URSOFC) can be considered as a next-generation power source and a storage device in the future since it can generate electricity in the SOFC mode and also produce H2/O2 in the solid oxide electrolyzer cell (SOEC) mode. In this paper, a two-dimensional axisymmetric model is developed to simulate the characteristics of a URSOFC. The performance curves for an in-house button URSOFC under different operating temperatures of 600, 700, and 800 °C are measured to validate the present model. Both the measured data and the prediction results reveal the beneficial effects of higher temperature on the cell performance. Based on the results of numerical simulations, the majority of the fuel gas is consumed at the interface of the electrolyte and the electrode, causing a great fuel concentration gradient near the interface. In addition, the predicted cell performance curves in both the SOFC and the SOEC modes correspond well with the measured data, demonstrating the applicability of this model in a button URSOFC. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The Fe–22Cr–0.5Mn ferritic stainless steel alloyed with Nb or with Mo is evaluated in the button cell configuration at 750 °C in terms of degradation in ohmic resistance and cathodic polarization resistance. STS444 and Crofer22 APU are also evaluated for comparison. Each polarization element is separated by equivalent circuit analysis on the electrochemical impedance spectroscopy data. Cr deposition on the button cell cathode is also analyzed both qualitatively by transmission electron microscope and quantitatively by inductively coupled plasma. The Nb- or Mo-alloyed ferritic stainless steel shows comparable performance with Crofer22 APU in terms of the increase rate in ohmic resistance and Cr evaporation rate, even without the addition of reactive element such as La. When the same amount of Cr is deposited on the cathode, the cathode performance deteriorates more at the high Cr evaporation rate than at the low Cr evaporation rate. [Copyright &y& Elsevier]

Abstract: Limiting current densities for solid oxide fuel cells were measured using both button cells and a flow-through cell. The cell anodes were supplied with mixtures of humidified hydrogen and various inert gasses. It was demonstrated that the true limiting current in flow-through cells is reached when either: the hydrogen is nearly or completely depleted at the anode-electrolyte interface near the outlet; or when the concentration of steam at that interface becomes high enough to interfere with adsorption or transport of the remaining hydrogen near the triple-phase boundaries. Choice of inert gas had no effect on limiting currents in the flow-through tests, indicating that diffusion within the porous anode had no significant effect on cell performance at high currents. In the button cells, the apparent limiting currents were significantly changed by the choice of inert gas, indicating that they were determined by diffusion through the bulk gas within the support tube. It was concluded that the apparent limiting currents measured in button cells are influenced more by parameters of the experimental setup, such as the proximity of the fuel tube outlet, than by the physical properties of the anode. [Copyright &y& Elsevier]

Abstract: In this study, a 2-D numerical model is investigated to predict and evaluate the performance of an anode-supported SOFC button cell. The flow field is calculated using 2D Navier–Stokes equations. Heat and mass transfer equations are solved to calculate species and temperature distribution in the cell body and in fuel and air channels. The electrical and electrochemical processes are simulated coupled with the heat and mass transfer model. A discretized network circuit is adopted to the cell geometry for considering the ohmic losses and joule heating of the current that passes through the cell body. The model predicts the cell output voltage, the local EMF and the state variables pressure, temperature and species concentrations. The local electrical parameters are calculated based on the local pressure, temperature and concentration of the species. The numerical results are compared with the experimental data and good agreement is observed. The simulation is carried out for different input fuel flow rates and humidification. The results show how the input fuel mass flow rate and humidification level affects the button cell SOFC performance. In addition, influences of the anode thickness on cell performance through the ohmic over potential are investigated. [ABSTRACT FROM AUTHOR]

Abstract: The quantitative analysis and interpretation of button-cell experiments usually depends upon assuming isothermal conditions together with uniform and known gas composition within the gas compartments. An objective of the present effort is to develop computational tools to study the validity of such assumptions. A three-dimensional computational fluid dynamics (CFD) model is developed and applied to a particular SOFC button cell, characterizing the fluid flow, chemistry, and thermal transport. Results show that when inlet flow rates are sufficiently high, button-cell data can be interpreted using the commonly used assumptions. However, when flow rates are not sufficient, the assumptions of uniform composition can be significantly violated. Additionally, depending on operating conditions there can be significant temperature variations within the gas compartments and the membrane–electrode assembly. [Copyright &y& Elsevier]

A case of button cell lodged in oesophagus is reported. The button cells are potentially destructive foreign bodies due to damage caused by leakage of harmful chemicals and their capability to generate electric current. The mucosal damage starts early and may lead to life threatening complications in long standing cases. Removal of these should be accorded highest priority to prevent complications. [ABSTRACT FROM AUTHOR]

Button battery incidents have become a rising medical issue in recent years, especially for infants. The increasing number of these cases can be explained by the expanding use of objects of everyday life and toys. As a result, button batteries in many households are ubiquitous in different states of charge. The extremely long shelf-life and the increasing energy densities of lithium button batteries boost the potential medical complications of accidental swallowing. The study aimed to analyze the pathophysiology of damage to tracheobronchial structures by button batteries aspiration over time. CR2032 and CR927 lithium button batteries (3.2/3.0 V) were exposed to porcine trachea preparations intraluminal at 37 °C in intervals up to 36 h. Measurements were made of the voltage curve, the discharge current, and the resulting pH values around the electrodes. The effects on tissue were examined using macroscopic time-lapse images and microscopic pictures of sections of the fixed specimens over time. The examinations showed a tissue electrolysis reaction directly after the beginning of battery exposure, which led to an immediate coagulation impairment of the respiratory epithelium. Over time, a strongly alkaline environment was established around the batteries. The resulting tissue colliquation caused profound tissue damage beyond the basal membrane of the mucosa, affecting the tracheobronchial cartilage after only 4 h of exposure time. After 12 h, there was significant necrosis of the annular ligaments of the trachea and the peribronchial pulmonary tissue. After completion of the experimental exposure time of 36 h, there was still a sufficient residual voltage on all button batteries of the experiments. Besides accidental ingestion, the aspiration of button batteries is a life-threatening situation. The partial or complete acute airway obstruction in the trachea or the bronchi initially is the leading symptom, as with any foreign body aspiration. However, the results of the investigations show that even after a short exposure time, relevant tissue damage can be caused by the electrolysis reaction of the battery. After 12 h, a profound destruction of cartilage, connective tissue, and smooth muscles was observed in vitro, which may cause significant consequential damage in vivo. These findings reveal the need for rapid diagnosis and immediate foreign body removal after any battery ingestion. Moreover, the results show how relevant prevention of these accidents is, and that future safety modifications of these types of battery by the manufacturers would be appropriate. [ABSTRACT FROM AUTHOR]