scholarly journals Versatile electrochemical cell for Li/Na-ion batteries and high-throughput setup for combinedoperandoX-ray diffraction and absorption spectroscopy

2016 ◽  
Vol 49 (6) ◽  
pp. 1972-1981 ◽  
Author(s):  
Jonas Sottmann ◽  
Roberto Homs-Regojo ◽  
David S. Wragg ◽  
Helmer Fjellvåg ◽  
Serena Margadonna ◽  
...  
Keyword(s):  
Electrode Materials ◽  
Electrochemical Cell ◽  
High Capacity ◽  
Electrochemical Cells ◽  
X Ray Diffraction ◽  
Composition Profiles ◽  
Multi Phase ◽  
Insight Into ◽  
Aqueous Batteries

A fundamental understanding of de/intercalation processes (single phaseversusmulti-phase), structural stability and voltage–composition profiles is pivotal for optimization of electrode materials for rechargeable non-aqueous batteries. A fully operational setup (electrochemical cells, sample changer and interfacing software) that enables combined quasi-simultaneousoperandoX-ray diffraction (XRD) and absorption (XANES and EXAFS) measurements coupled with electrochemical characterization is presented. Combined XRD, XANES and EXAFS analysis provides a deep insight into the working mechanisms of electrode materials, as shown for the high-voltage Li insertion cathode material LiMn1.5Ni0.5O4and the high-capacity sodium conversion anode material Bi2S3. It is also demonstrated that the cell design can be used for in-house XRD characterization. Long-term cycling experiments on both Li and Na electrode materials prove the hermeticity and chemical stability of the design as a versatileoperandoelectrochemical cell.

Rechargeable nonaqueous lithium/Mo6S8 battery

1984 ◽  
Vol 62 (6) ◽  
pp. 527-531 ◽  
Author(s):  
P. J. Mulhern ◽  
R. R. Haering
Keyword(s):  
Discharge Rate ◽  
Active Material ◽  
Rate Capability ◽  
Constant Current ◽  
Electrochemical Cells ◽  
X Ray Diffraction ◽  
X Ray ◽  
Long Cycle Life

Electrochemical cells based on the intercalation of lithium into Mo6S8 were examined by derivative constant current chronopotentiometry, in situ X-ray diffraction, and long-term cycling. About three-quarters of the capacity of such cells oeeurs between 2.0 and 2.1 V with most of the remainder near 2.45 V. Li/Mo6S8 cells have a long cycle life, good discharge rate capability, and an energy density of at least 260 W∙h/kg (1 W∙h = 3.6 kJ) of active material. Such cells can be made by starting with cathodes made from ternary Chevrel phase compounds. AyMo6S8 (A = Cu, Fe, Ni), and electrochemically converting these materials to form LixMo6S8.

scholarly journals Insight Into Disorder, Stress and Strain of Radiation Damaged Pyrochlores: A Possible Mechanism for the Appearance of Defect Fluorite

2021 ◽  
Vol 9 ◽  
Author(s):  
Sarah C. Finkeldei ◽  
Shirley Chang ◽  
Mihail Ionescu ◽  
Daniel Oldfield ◽  
Joel Davis ◽  
...  
Keyword(s):  
Storage Conditions ◽  
Sample Volume ◽  
X Ray Diffraction ◽  
Pristine Sample ◽  
Waste Storage ◽  
Full Analysis ◽  
Diffraction Patterns ◽  
Displacement Per Atom ◽  
Insight Into

We have examined the irradiation response of a titanate and zirconate pyrochlore—both of which are well studied in the literature individually—in an attempt to define the appearance of defect fluorite in zirconate pyrochlores. To our knowledge this study is unique in that it attempts to discover the mechanism of formation by a comparison of the different systems exposed to the same conditions and then examined via a range of techniques that cover a wide length scale. The conditions of approximately 1 displacement per atom via He2+ ions were used to simulate long term waste storage conditions as outlined by previous results from Ewing in a large enough sample volume to allow for neutron diffraction, as not attempted previously. The titanate sample, used as a baseline comparison since it readily becomes amorphous under these conditions behaved as expected. In contrast, the zirconate sample accumulates tensile stress in the absence of detectable strain. We propose this is analogous to the lanthanide zirconate pyrochlores examined by Simeone et al. where they reported the appearance of defect fluorite diffraction patterns due to a reduction in grain size. Radiation damage and stress results in the grains breaking into even smaller crystallites, thus creating even smaller coherent diffraction domains. An (ErNd)2(ZrTi)2O7 pyrochlore was synthesized to examine which mechanism might dominate, amorphization or stress/strain build up. Although strain was detected in the pristine sample via Synchrotron X-ray diffraction it was not of sufficient quality to perform a full analysis on.

scholarly journals An Electrochemical Desalination Cell Based On Conducting Polymers

2018 ◽  
Vol 21 (1) ◽  
pp. 101
Author(s):  
Walter Torres Hernández
Keyword(s):  
Water Conservation ◽  
Potable Water ◽  
Electrochemical Cell ◽  
Carbon Electrodes ◽  
Electrochemical Cells ◽  
Polystyrene Sulfonate ◽  
Conservation Policies ◽  
Long Term Stability ◽  
Exchange Properties

Insufficient  access  to  potable  water  is  becoming  one  of  the  major  threats  to  sustainable development around the globe. The implementation of water conservation policies and the use of mature and novel desalination technologies are key to address the water demand for an increasing population. Desalination systems based on electrochemical cells are of current interest. This paper discusses an electrochemical cell based on carbon electrodes modified with polypyrrole and  a  polypyrrole/polystyrene  sulfonate  composite  which  have  anion  and  cation  exchange properties, respectively. The cell was used to substantially decrease the concentration of sodium chloride solution in the 10 -1  and the 10 -2  M concentration range. The long term stability of this cell is also discusse

Quantifying Slow Diffusion in High Capacity, Multi-Phase Electrode Materials

2020 ◽  
Vol MA2020-02 (2) ◽  
pp. 406-406
Author(s):  
Sara Early ◽  
Eliana Feygin ◽  
Mohammedreza Zamanzad Ghavidel ◽  
Shaochen Ding ◽  
Oles Sendetskyi ◽  
...  
Keyword(s):  
Electrode Materials ◽  
High Capacity ◽  
Slow Diffusion ◽  
Multi Phase

scholarly journals Spatially Resolved Operando Synchrotron-Based X-Ray Diffraction Measurements of Ni-Rich Cathodes for Li-Ion Batteries

2022 ◽  
Vol 3 ◽  
Author(s):  
Andrew Stephen Leach ◽  
Alice V. Llewellyn ◽  
Chao Xu ◽  
Chun Tan ◽  
Thomas M. M. Heenan ◽  
...  
Keyword(s):  
High Capacity ◽  
Lithium Ion ◽  
Lower Percentage ◽  
Li Ion Batteries ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spatially Resolved ◽  
Electrochemical Cycling ◽  
Li Ion

Understanding the performance of commercially relevant cathode materials for lithium-ion (Li-ion) batteries is vital to realize the potential of high-capacity materials for automotive applications. Of particular interest is the spatial variation of crystallographic behavior across (what can be) highly inhomogeneous electrodes. In this work, a high-resolution X-ray diffraction technique was used to obtain operando transmission measurements of Li-ion pouch cells to measure the spatial variances in the cell during electrochemical cycling. Through spatially resolved investigations of the crystallographic structures, the distribution of states of charge has been elucidated. A larger portion of the charging is accounted for by the central parts, with the edges and corners delithiating to a lesser extent for a given average electrode voltage. The cells were cycled to different upper cutoff voltages (4.2 and 4.3 V vs. graphite) and C-rates (0.5, 1, and 3C) to study the effect on the structure of the NMC811 cathode. By combining this rapid data collection method with a detailed Rietveld refinement of degraded NMC811, the spatial dependence of the degradation caused by long-term cycling (900 cycles) has also been shown. The variance shown in the pristine measurements is exaggerated in the aged cells with the edges and corners offering an even lower percentage of the charge. Measurements collected at the very edge of the cell have also highlighted the importance of electrode alignment, with a misalignment of less than 0.5 mm leading to significantly reduced electrochemical activity in that area.

scholarly journals A novel electrochemical cell forin situneutron diffraction studies of electrode materials for lithium-ion batteries

2008 ◽  
Vol 41 (4) ◽  
pp. 690-694 ◽  
Author(s):  
Fabio Rosciano ◽  
Michael Holzapfel ◽  
Werner Scheifele ◽  
Petr Novák
Keyword(s):  
Neutron Diffraction ◽  
Lithium Ion Batteries ◽  
Electrode Materials ◽  
Electrochemical Cell ◽  
Lithium Ion ◽  
X Ray Diffraction ◽  
Lithium Ions ◽  
Host Materials ◽  
Established Technique

Lithium-ion batteries are based on the principle of intercalation of lithium ions in host materials, both at the anode and at the cathode. These materials are in general crystalline and, during the operation of the battery, they undergo numerous phase transitions and structural rearrangements, often amplified by the presence of an applied potential difference. Whilein situX-ray diffraction is an established technique in this field,in situneutron diffraction is still in its pioneering stages and only a few attempts have been made to design an electrochemical cell suitable for these experiments. The technical development of such a device, along with a discussion of its serviceability to combine electrochemical measurements with neutron diffraction experiments, is hereby presented.

Turkish Muslims in a German city: Entrepreneurial and residential self-determination

2015 ◽  
Vol 12 (1) ◽  
pp. 1-12
Author(s):  
Sarah Hackett
Keyword(s):  
Residential Patterns ◽  
Academic Literature ◽  
Self Employment ◽  
German City ◽  
Post War ◽  
Oral History Interviews ◽  
The City ◽  
Insight Into ◽  
Term Objective

Drawing upon a collection of oral history interviews, this paper offers an insight into entrepreneurial and residential patterns and behaviour amongst Turkish Muslims in the German city of Bremen. The academic literature has traditionally argued that Turkish migrants in Germany have been pushed into self-employment, low-quality housing and segregated neighbourhoods as a result of discrimination, and poor employment and housing opportunities. Yet the interviews reveal the extent to which Bremen’s Turkish Muslims’ performances and experiences have overwhelmingly been the consequences of personal choices and ambitions. For many of the city’s Turkish Muslim entrepreneurs, self-employment had been a long-term objective, and they have succeeded in establishing and running their businesses in the manner they choose with regards to location and clientele, for example. Similarly, interviewees stressed the way in which they were able to shape their housing experiences by opting which districts of the city to live in and by purchasing property. On the whole, they perceive their entrepreneurial and residential practices as both consequences and mediums of success, integration and a loyalty to the city of Bremen. The findings are contextualised within the wider debate regarding the long-term legacy of Germany’s post-war guest-worker system and its position as a “country of immigration”.

Photo-Current Enhancement at Cu/p-Cu2O/rGO- Electrolyte Interface

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
S.P.A.U.K. Samarakoon ◽  
C.A.N. Fernando
Keyword(s):  
Diffuse Reflectance ◽  
Electrochemical Cell ◽  
Time Development ◽  
Charge Carriers ◽  
Electrochemical Cells ◽  
Current Action ◽  
Electrolyte Interface ◽  
Reduced Graphene ◽  
Efficient Charge ◽  
Photo Current

A considerable photo-current enhancement was found at the Cu/p-Cu2O/rGO-electrolyte interface in a photo-electrochemical cell with compared to that of Cu/p-Cu2O-electrolyte interface. The reason for the photo-current enhancement may be due to the efficient charge separation process provided at Cu/p-Cu2O/rGO-electrolyte interface. Here rGO (reduced graphene oxide) acts as an electron acceptor for the photo-generated charge carriers as it readily accept electrons from the conduction band of p-Cu2O. rGO was synthesized using electro-phoretic deposition (EPD) technique. Fabricated samples were characterized using diffuse reflectance spectra, photo-current action spectra and the time development of the photocurrent of photo-electrochemical cells.

Restoration of cylinder liners for automotive tractors engines in modern conditions

2020 ◽  
pp. 122-133
Author(s):  
Vyacheslav A. Denisov ◽  
Aleksandr Yu. Kostyukov ◽  
Roman N. Zadorozhniy
Keyword(s):  
Adhesion Strength ◽  
Electrode Materials ◽  
Research Purpose ◽  
Laboratory Studies ◽  
Term Operation ◽  
Operational Load ◽  
Operational Tests ◽  
Conducting Research ◽  
Cylinder Liners

One of the most promising technologies for restoring machine parts and cylinder liners is electric spark treatment as the most versatile technology that provides high-quality restoration of worn parts with wear up to 0.5 mm. (Research purpose) The research purpose is in developing a technology for restoring various cylinder liners by means of electric spark processing, selecting optimal modes and electrode materials that allow improving the quality of repair and increasing the post-repair life of the sleeve. (Materials and methods) It was taken into account when conducting research aimed at restoring the geometric parameters of the sleeve, that the coating must have sufficient adhesion strength to the surface of the sleeve under mechanical, thermal loads and long-term operation. Laboratory studies of the adhesion strength of electric spark coatings on the separation (adhesive) and on the cut, as well as tribotechnical studies of interfaces were conducted. Authors have found by analyzing the results of operational tests of restored and new cylinder liners the prospects for using electric spark treatment of worn parts, including diesel engine liners. (Results and discussion) It was shown by laboratory studies of the adhesion strength of electric spark coatings with a 0.2 mm thick BrMKc 3-1 electrode to the working surface of cylinder liners that their separation strength (adhesive) was 20-40 megapascals, and the shear strength (cohesive) was 50-80 megapascals. It was found that this provides the required functional strength of coatings with maximum operational load. The article presents the results of comprehensive research in graphs and tables. (Conclusions) The research conducted in the CCP "Nano-Center" of the FSAC VIM and operational tests in the 2nd bus fleet of Moscow confirmed the principal possibility of effectively restoring cast iron liners (blocks) using the technology of electric spark processing.

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